Re: [time-nuts] Modern motherboard with RS232 port
I like to think of it this way: If you are talking instantaneous measurements, then watts is indeed always volts * amps. With a resistive load, the signs of volts and amps are always the same, and the product of the two is always non-negative. If you calculate the average of instantaneous watts over time, you get average power. If you have an inductive load, watts is still volts * amps. But the phase shift between current and voltage means that the instantaneous power is sometimes negative, which means that the load is (at that instant) returning power to the source. But averaging instantaneous watts, both positive and negative values, still gives you average power. The problem comes when we want to calculate watts with devices that only measure voltage, or only measure current. With a resistive load, where the instantaneous power is never negative, you can calculate power by measuring only voltage, calculating the RMS voltage, and knowing the resistance. But that doesn't work for non-resistive loads because the instantaneous current is no longer proportional to the instantaneous voltage. If both are still sinusoidal, knowing the phase shift lets you calculate power. But that doesn't work either for arbitrary waveforms. Dave On Sun, Aug 19, 2012 at 10:32 PM, Chuck Harris cfhar...@erols.com wrote: The long and the short of it is that when AC encounters a reactive load, it results in a current that is not in phase with the voltage. Power is equal to volts x amps only when the current and voltage are in phase which can only happen if the load is purely resistive. If you hang a perfect capacitor across the power line, or a perfect inductor, you will draw lots of current, but no power. -Chuck Harris Tom Knox wrote: Hi Ed; I may not have had enough coffee yet, but if Volt X Amps = Watts why would there be a difference? Best Wishes; Thomas Knox __**_ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/** mailman/listinfo/time-nutshttps://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Modern motherboard with RS232 port
Isn't that what I said? Jim Lux wrote: On 8/19/12 7:26 PM, Chuck Harris wrote: Residential power is traditionally measured in watts, not V-A. Commercial power is typically measured in V-A, with an additional fee for power factor problems. residential meters measure watts (active power) not VA... What you want is the Kill-A-Watt.. a $30 widget that measures all the parameters.. A great little deviec. -Chuck Harris ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Modern motherboard with RS232 port
On 19 August 2012 20:34, Sarah White kuze...@gmail.com wrote: The difference between volt-amp versus RMS watt versus peak watts, etc, etc. can be off by more than you'd expect. An RMS watt is a useless term. Sure one can calcualte the RMS value of power, but the number has no practical significance, unlike mean power, which has the same heating effect, irrespective of the waveform. Dave ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Modern motherboard with RS232 port
This sounds like a newer version of the board I use. The thing to check is if the CPU heat sink has a fan or not. Having no fan indicates that the CPU is not using much power. It also removes a common failure point. To reduce power even more. On an NTP server you can unplug the keyboard, mouse and monitor and if you have other servers on the LAN configure one as a boot server and have it run TFTP then your NTP server does not need a disk drive. It can run off a RAM disk. This makes it very fast, even faster than a SSD and it saves some cash. Makes backup easy too as there is nothing to backup if there is no local storage. If you don't have a TFTP server use a small notebook size disk drive. Even a 80GB drive is overkill. You can also boot from a USB thumb drive and run a RAM disk. It is worth it to look at your electric bill to find how much you pay for power. Here I'm at $0.21 per KWH. A full size PC server can use 250W or more. There are 8760 hours in a year so you get $460 per year to run that 250W PC. The little Atom will pay for itself in just a few months. The first time I did that calculation, my power hogs where given away. On Sun, Aug 19, 2012 at 7:42 AM, Stan, W1LE stanw...@verizon.net wrote: Hello The Net, For your consideration: The INTEL model DN2800mt ITX mother board uses a ATOM CPU and draws about 11 watts of AC power when configured as: (I have not measured DC power yet.) 30 GB OCZ Nocti mSATA solid state drive, WIN7 pro, 64 bit, USB keyboard and mouse APEX MI-0008 case. Also has: parallel port available on mother board, you extend to a connector RS232 serial port available on mother board, you extend to a connector a single DC power supply from 11 to 19 V DC. 1 each PCIe expansion port, I will use with a premium 4 channel sound card SATA ports available for HDD/SDD, USB ports are available, Motherboard sound, and Gigalan. I have not played with NTP, (yet), but it sounds like a decent time nut technical challenge. My application is for a remote site with only 13V DC power available from PV/batteries. Then use fiber ethernet to get off site. The INTEL website would have further details. Stan, W1LECape Cod FN41sr z __**_ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/** mailman/listinfo/time-nutshttps://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. -- Chris Albertson Redondo Beach, California ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Modern motherboard with RS232 port
Why not just use a raspberry pi? Uses a whole 2w at idle. Ntp might bump that to 2.01. On Aug 19, 2012, at 13:06, Chris Albertson albertson.ch...@gmail.com wrote: This sounds like a newer version of the board I use. The thing to check is if the CPU heat sink has a fan or not. Having no fan indicates that the CPU is not using much power. It also removes a common failure point. To reduce power even more. On an NTP server you can unplug the keyboard, mouse and monitor and if you have other servers on the LAN configure one as a boot server and have it run TFTP then your NTP server does not need a disk drive. It can run off a RAM disk. This makes it very fast, even faster than a SSD and it saves some cash. Makes backup easy too as there is nothing to backup if there is no local storage. If you don't have a TFTP server use a small notebook size disk drive. Even a 80GB drive is overkill. You can also boot from a USB thumb drive and run a RAM disk. It is worth it to look at your electric bill to find how much you pay for power. Here I'm at $0.21 per KWH. A full size PC server can use 250W or more. There are 8760 hours in a year so you get $460 per year to run that 250W PC. The little Atom will pay for itself in just a few months. The first time I did that calculation, my power hogs where given away. On Sun, Aug 19, 2012 at 7:42 AM, Stan, W1LE stanw...@verizon.net wrote: Hello The Net, For your consideration: The INTEL model DN2800mt ITX mother board uses a ATOM CPU and draws about 11 watts of AC power when configured as: (I have not measured DC power yet.) 30 GB OCZ Nocti mSATA solid state drive, WIN7 pro, 64 bit, USB keyboard and mouse APEX MI-0008 case. Also has: parallel port available on mother board, you extend to a connector RS232 serial port available on mother board, you extend to a connector a single DC power supply from 11 to 19 V DC. 1 each PCIe expansion port, I will use with a premium 4 channel sound card SATA ports available for HDD/SDD, USB ports are available, Motherboard sound, and Gigalan. I have not played with NTP, (yet), but it sounds like a decent time nut technical challenge. My application is for a remote site with only 13V DC power available from PV/batteries. Then use fiber ethernet to get off site. The INTEL website would have further details. Stan, W1LECape Cod FN41sr z __**_ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/** mailman/listinfo/time-nutshttps://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. -- Chris Albertson Redondo Beach, California ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Modern motherboard with RS232 port
Hi Onboard ethernet on the pi model B is hooked into the CPU via the USB port. That may not be best for accurate time. Bob On Aug 19, 2012, at 1:16 PM, bownes bow...@gmail.com wrote: Why not just use a raspberry pi? Uses a whole 2w at idle. Ntp might bump that to 2.01. On Aug 19, 2012, at 13:06, Chris Albertson albertson.ch...@gmail.com wrote: This sounds like a newer version of the board I use. The thing to check is if the CPU heat sink has a fan or not. Having no fan indicates that the CPU is not using much power. It also removes a common failure point. To reduce power even more. On an NTP server you can unplug the keyboard, mouse and monitor and if you have other servers on the LAN configure one as a boot server and have it run TFTP then your NTP server does not need a disk drive. It can run off a RAM disk. This makes it very fast, even faster than a SSD and it saves some cash. Makes backup easy too as there is nothing to backup if there is no local storage. If you don't have a TFTP server use a small notebook size disk drive. Even a 80GB drive is overkill. You can also boot from a USB thumb drive and run a RAM disk. It is worth it to look at your electric bill to find how much you pay for power. Here I'm at $0.21 per KWH. A full size PC server can use 250W or more. There are 8760 hours in a year so you get $460 per year to run that 250W PC. The little Atom will pay for itself in just a few months. The first time I did that calculation, my power hogs where given away. On Sun, Aug 19, 2012 at 7:42 AM, Stan, W1LE stanw...@verizon.net wrote: Hello The Net, For your consideration: The INTEL model DN2800mt ITX mother board uses a ATOM CPU and draws about 11 watts of AC power when configured as: (I have not measured DC power yet.) 30 GB OCZ Nocti mSATA solid state drive, WIN7 pro, 64 bit, USB keyboard and mouse APEX MI-0008 case. Also has: parallel port available on mother board, you extend to a connector RS232 serial port available on mother board, you extend to a connector a single DC power supply from 11 to 19 V DC. 1 each PCIe expansion port, I will use with a premium 4 channel sound card SATA ports available for HDD/SDD, USB ports are available, Motherboard sound, and Gigalan. I have not played with NTP, (yet), but it sounds like a decent time nut technical challenge. My application is for a remote site with only 13V DC power available from PV/batteries. Then use fiber ethernet to get off site. The INTEL website would have further details. Stan, W1LECape Cod FN41sr z __**_ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/** mailman/listinfo/time-nutshttps://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. -- Chris Albertson Redondo Beach, California ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Modern motherboard with RS232 port
On Sun, Aug 19, 2012 at 10:16 AM, bownes bow...@gmail.com wrote: Why not just use a raspberry pi? Uses a whole 2w at idle. Ntp might bump that to 2.01. You certainly could run ntpd on that box. But I wonder how the PPS is supported in hardware? What is the standard deviation of interrupt latency on the DCD pin on the serial port. Perhaps some one who has a pi could measure this. All the data should be in the system log as each PPS is time stamped and written to the log. If the DCD pin is polled you are not going to get decent results. Maybe someone could read the PPS drive code. -- Chris Albertson Redondo Beach, California ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Modern motherboard with RS232 port
It's important to remember that on a computer, the wattage shown has no relationship to the wattage pulled from the socket. The numbers shown are maximum values. You have to measure the power draw and you have to measure it in volt-amps, not watts because that's how residential power is measured (at least in North America). Buy an energy meter that shows volt-amps. They're relatively cheap - typically less than $50. Ed On 8/19/2012 11:06 AM, Chris Albertson wrote: This sounds like a newer version of the board I use. The thing to check is if the CPU heat sink has a fan or not. Having no fan indicates that the CPU is not using much power. It also removes a common failure point. To reduce power even more. On an NTP server you can unplug the keyboard, mouse and monitor and if you have other servers on the LAN configure one as a boot server and have it run TFTP then your NTP server does not need a disk drive. It can run off a RAM disk. This makes it very fast, even faster than a SSD and it saves some cash. Makes backup easy too as there is nothing to backup if there is no local storage. If you don't have a TFTP server use a small notebook size disk drive. Even a 80GB drive is overkill. You can also boot from a USB thumb drive and run a RAM disk. It is worth it to look at your electric bill to find how much you pay for power. Here I'm at $0.21 per KWH. A full size PC server can use 250W or more. There are 8760 hours in a year so you get $460 per year to run that 250W PC. The little Atom will pay for itself in just a few months. The first time I did that calculation, my power hogs where given away. On Sun, Aug 19, 2012 at 7:42 AM, Stan, W1LE stanw...@verizon.net wrote: Hello The Net, For your consideration: The INTEL model DN2800mt ITX mother board uses a ATOM CPU and draws about 11 watts of AC power when configured as: (I have not measured DC power yet.) 30 GB OCZ Nocti mSATA solid state drive, WIN7 pro, 64 bit, USB keyboard and mouse APEX MI-0008 case. Also has: parallel port available on mother board, you extend to a connector RS232 serial port available on mother board, you extend to a connector a single DC power supply from 11 to 19 V DC. 1 each PCIe expansion port, I will use with a premium 4 channel sound card SATA ports available for HDD/SDD, USB ports are available, Motherboard sound, and Gigalan. I have not played with NTP, (yet), but it sounds like a decent time nut technical challenge. My application is for a remote site with only 13V DC power available from PV/batteries. Then use fiber ethernet to get off site. The INTEL website would have further details. Stan, W1LECape Cod FN41sr z ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Modern motherboard with RS232 port
Hi Ed; I may not have had enough coffee yet, but if Volt X Amps = Watts why would there be a difference? Best Wishes; Thomas Knox Date: Sun, 19 Aug 2012 12:35:51 -0600 From: ed_pal...@sasktel.net To: time-nuts@febo.com Subject: Re: [time-nuts] Modern motherboard with RS232 port It's important to remember that on a computer, the wattage shown has no relationship to the wattage pulled from the socket. The numbers shown are maximum values. You have to measure the power draw and you have to measure it in volt-amps, not watts because that's how residential power is measured (at least in North America). Buy an energy meter that shows volt-amps. They're relatively cheap - typically less than $50. Ed On 8/19/2012 11:06 AM, Chris Albertson wrote: This sounds like a newer version of the board I use. The thing to check is if the CPU heat sink has a fan or not. Having no fan indicates that the CPU is not using much power. It also removes a common failure point. To reduce power even more. On an NTP server you can unplug the keyboard, mouse and monitor and if you have other servers on the LAN configure one as a boot server and have it run TFTP then your NTP server does not need a disk drive. It can run off a RAM disk. This makes it very fast, even faster than a SSD and it saves some cash. Makes backup easy too as there is nothing to backup if there is no local storage. If you don't have a TFTP server use a small notebook size disk drive. Even a 80GB drive is overkill. You can also boot from a USB thumb drive and run a RAM disk. It is worth it to look at your electric bill to find how much you pay for power. Here I'm at $0.21 per KWH. A full size PC server can use 250W or more. There are 8760 hours in a year so you get $460 per year to run that 250W PC. The little Atom will pay for itself in just a few months. The first time I did that calculation, my power hogs where given away. On Sun, Aug 19, 2012 at 7:42 AM, Stan, W1LE stanw...@verizon.net wrote: Hello The Net, For your consideration: The INTEL model DN2800mt ITX mother board uses a ATOM CPU and draws about 11 watts of AC power when configured as: (I have not measured DC power yet.) 30 GB OCZ Nocti mSATA solid state drive, WIN7 pro, 64 bit, USB keyboard and mouse APEX MI-0008 case. Also has: parallel port available on mother board, you extend to a connector RS232 serial port available on mother board, you extend to a connector a single DC power supply from 11 to 19 V DC. 1 each PCIe expansion port, I will use with a premium 4 channel sound card SATA ports available for HDD/SDD, USB ports are available, Motherboard sound, and Gigalan. I have not played with NTP, (yet), but it sounds like a decent time nut technical challenge. My application is for a remote site with only 13V DC power available from PV/batteries. Then use fiber ethernet to get off site. The INTEL website would have further details. Stan, W1LECape Cod FN41sr z ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Modern motherboard with RS232 port
Ed: you're sorta right, but only on a really basic level of electrical engineering. Induction and capacitance and random transformer magnetic flux nonsense that makes AC currents act in unexpected ways. The difference between volt-amp versus RMS watt versus peak watts, etc, etc. can be off by more than you'd expect. It really comes into play when you're trying to build power supplies (regulated or otherwise) On 8/19/2012 3:19 PM, Tom Knox wrote: Hi Ed; I may not have had enough coffee yet, but if Volt X Amps = Watts why would there be a difference? Best Wishes; Thomas Knox Date: Sun, 19 Aug 2012 12:35:51 -0600 From: ed_pal...@sasktel.net To: time-nuts@febo.com Subject: Re: [time-nuts] Modern motherboard with RS232 port It's important to remember that on a computer, the wattage shown has no relationship to the wattage pulled from the socket. The numbers shown are maximum values. You have to measure the power draw and you have to measure it in volt-amps, not watts because that's how residential power is measured (at least in North America). Buy an energy meter that shows volt-amps. They're relatively cheap - typically less than $50. Ed On 8/19/2012 11:06 AM, Chris Albertson wrote: This sounds like a newer version of the board I use. The thing to check is if the CPU heat sink has a fan or not. Having no fan indicates that the CPU is not using much power. It also removes a common failure point. To reduce power even more. On an NTP server you can unplug the keyboard, mouse and monitor and if you have other servers on the LAN configure one as a boot server and have it run TFTP then your NTP server does not need a disk drive. It can run off a RAM disk. This makes it very fast, even faster than a SSD and it saves some cash. Makes backup easy too as there is nothing to backup if there is no local storage. If you don't have a TFTP server use a small notebook size disk drive. Even a 80GB drive is overkill. You can also boot from a USB thumb drive and run a RAM disk. It is worth it to look at your electric bill to find how much you pay for power. Here I'm at $0.21 per KWH. A full size PC server can use 250W or more. There are 8760 hours in a year so you get $460 per year to run that 250W PC. The little Atom will pay for itself in just a few months. The first time I did that calculation, my power hogs where given away. On Sun, Aug 19, 2012 at 7:42 AM, Stan, W1LE stanw...@verizon.net wrote: Hello The Net, For your consideration: The INTEL model DN2800mt ITX mother board uses a ATOM CPU and draws about 11 watts of AC power when configured as: (I have not measured DC power yet.) 30 GB OCZ Nocti mSATA solid state drive, WIN7 pro, 64 bit, USB keyboard and mouse APEX MI-0008 case. Also has: parallel port available on mother board, you extend to a connector RS232 serial port available on mother board, you extend to a connector a single DC power supply from 11 to 19 V DC. 1 each PCIe expansion port, I will use with a premium 4 channel sound card SATA ports available for HDD/SDD, USB ports are available, Motherboard sound, and Gigalan. I have not played with NTP, (yet), but it sounds like a decent time nut technical challenge. My application is for a remote site with only 13V DC power available from PV/batteries. Then use fiber ethernet to get off site. The INTEL website would have further details. Stan, W1LECape Cod FN41sr z ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Modern motherboard with RS232 port
Power factor. -Original Message- From: Tom Knox act...@hotmail.com Sender: time-nuts-boun...@febo.com Date: Sun, 19 Aug 2012 13:19:20 To: Time-Nutstime-nuts@febo.com Reply-To: Discussion of precise time and frequency measurement time-nuts@febo.com Subject: Re: [time-nuts] Modern motherboard with RS232 port Hi Ed; I may not have had enough coffee yet, but if Volt X Amps = Watts why would there be a difference? Best Wishes; Thomas Knox Date: Sun, 19 Aug 2012 12:35:51 -0600 From: ed_pal...@sasktel.net To: time-nuts@febo.com Subject: Re: [time-nuts] Modern motherboard with RS232 port It's important to remember that on a computer, the wattage shown has no relationship to the wattage pulled from the socket. The numbers shown are maximum values. You have to measure the power draw and you have to measure it in volt-amps, not watts because that's how residential power is measured (at least in North America). Buy an energy meter that shows volt-amps. They're relatively cheap - typically less than $50. Ed On 8/19/2012 11:06 AM, Chris Albertson wrote: This sounds like a newer version of the board I use. The thing to check is if the CPU heat sink has a fan or not. Having no fan indicates that the CPU is not using much power. It also removes a common failure point. To reduce power even more. On an NTP server you can unplug the keyboard, mouse and monitor and if you have other servers on the LAN configure one as a boot server and have it run TFTP then your NTP server does not need a disk drive. It can run off a RAM disk. This makes it very fast, even faster than a SSD and it saves some cash. Makes backup easy too as there is nothing to backup if there is no local storage. If you don't have a TFTP server use a small notebook size disk drive. Even a 80GB drive is overkill. You can also boot from a USB thumb drive and run a RAM disk. It is worth it to look at your electric bill to find how much you pay for power. Here I'm at $0.21 per KWH. A full size PC server can use 250W or more. There are 8760 hours in a year so you get $460 per year to run that 250W PC. The little Atom will pay for itself in just a few months. The first time I did that calculation, my power hogs where given away. On Sun, Aug 19, 2012 at 7:42 AM, Stan, W1LE stanw...@verizon.net wrote: Hello The Net, For your consideration: The INTEL model DN2800mt ITX mother board uses a ATOM CPU and draws about 11 watts of AC power when configured as: (I have not measured DC power yet.) 30 GB OCZ Nocti mSATA solid state drive, WIN7 pro, 64 bit, USB keyboard and mouse APEX MI-0008 case. Also has: parallel port available on mother board, you extend to a connector RS232 serial port available on mother board, you extend to a connector a single DC power supply from 11 to 19 V DC. 1 each PCIe expansion port, I will use with a premium 4 channel sound card SATA ports available for HDD/SDD, USB ports are available, Motherboard sound, and Gigalan. I have not played with NTP, (yet), but it sounds like a decent time nut technical challenge. My application is for a remote site with only 13V DC power available from PV/batteries. Then use fiber ethernet to get off site. The INTEL website would have further details. Stan, W1LECape Cod FN41sr z ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Modern motherboard with RS232 port
There is no difference for a resistive load. For a reactive load, you have to take in account the phase angle between the current and the voltage. If I remember correctly, power = Volts X Amps X cosine of the phase angle. Some refer to the phase angle as the power factor. John WA4WDL -- From: Tom Knox act...@hotmail.com Sent: Sunday, August 19, 2012 3:19 PM To: Time-Nuts time-nuts@febo.com Subject: Re: [time-nuts] Modern motherboard with RS232 port Hi Ed; I may not have had enough coffee yet, but if Volt X Amps = Watts why would there be a difference? Best Wishes; Thomas Knox Date: Sun, 19 Aug 2012 12:35:51 -0600 From: ed_pal...@sasktel.net To: time-nuts@febo.com Subject: Re: [time-nuts] Modern motherboard with RS232 port It's important to remember that on a computer, the wattage shown has no relationship to the wattage pulled from the socket. The numbers shown are maximum values. You have to measure the power draw and you have to measure it in volt-amps, not watts because that's how residential power is measured (at least in North America). Buy an energy meter that shows volt-amps. They're relatively cheap - typically less than $50. Ed On 8/19/2012 11:06 AM, Chris Albertson wrote: This sounds like a newer version of the board I use. The thing to check is if the CPU heat sink has a fan or not. Having no fan indicates that the CPU is not using much power. It also removes a common failure point. To reduce power even more. On an NTP server you can unplug the keyboard, mouse and monitor and if you have other servers on the LAN configure one as a boot server and have it run TFTP then your NTP server does not need a disk drive. It can run off a RAM disk. This makes it very fast, even faster than a SSD and it saves some cash. Makes backup easy too as there is nothing to backup if there is no local storage. If you don't have a TFTP server use a small notebook size disk drive. Even a 80GB drive is overkill. You can also boot from a USB thumb drive and run a RAM disk. It is worth it to look at your electric bill to find how much you pay for power. Here I'm at $0.21 per KWH. A full size PC server can use 250W or more. There are 8760 hours in a year so you get $460 per year to run that 250W PC. The little Atom will pay for itself in just a few months. The first time I did that calculation, my power hogs where given away. On Sun, Aug 19, 2012 at 7:42 AM, Stan, W1LE stanw...@verizon.net wrote: Hello The Net, For your consideration: The INTEL model DN2800mt ITX mother board uses a ATOM CPU and draws about 11 watts of AC power when configured as: (I have not measured DC power yet.) 30 GB OCZ Nocti mSATA solid state drive, WIN7 pro, 64 bit, USB keyboard and mouse APEX MI-0008 case. Also has: parallel port available on mother board, you extend to a connector RS232 serial port available on mother board, you extend to a connector a single DC power supply from 11 to 19 V DC. 1 each PCIe expansion port, I will use with a premium 4 channel sound card SATA ports available for HDD/SDD, USB ports are available, Motherboard sound, and Gigalan. I have not played with NTP, (yet), but it sounds like a decent time nut technical challenge. My application is for a remote site with only 13V DC power available from PV/batteries. Then use fiber ethernet to get off site. The INTEL website would have further details. Stan, W1LECape Cod FN41sr z ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Modern motherboard with RS232 port
If you live near a Fry's, get a basic Kill-A-Watt. About $20. Often less on sale. You don't need the fancy version that computes cost versus time of day, etc. -Original Message- From: Ed Palmer ed_pal...@sasktel.net Sender: time-nuts-boun...@febo.com Date: Sun, 19 Aug 2012 12:35:51 To: Discussion of precise time and frequency measurementtime-nuts@febo.com Reply-To: Discussion of precise time and frequency measurement time-nuts@febo.com Subject: Re: [time-nuts] Modern motherboard with RS232 port It's important to remember that on a computer, the wattage shown has no relationship to the wattage pulled from the socket. The numbers shown are maximum values. You have to measure the power draw and you have to measure it in volt-amps, not watts because that's how residential power is measured (at least in North America). Buy an energy meter that shows volt-amps. They're relatively cheap - typically less than $50. Ed On 8/19/2012 11:06 AM, Chris Albertson wrote: This sounds like a newer version of the board I use. The thing to check is if the CPU heat sink has a fan or not. Having no fan indicates that the CPU is not using much power. It also removes a common failure point. To reduce power even more. On an NTP server you can unplug the keyboard, mouse and monitor and if you have other servers on the LAN configure one as a boot server and have it run TFTP then your NTP server does not need a disk drive. It can run off a RAM disk. This makes it very fast, even faster than a SSD and it saves some cash. Makes backup easy too as there is nothing to backup if there is no local storage. If you don't have a TFTP server use a small notebook size disk drive. Even a 80GB drive is overkill. You can also boot from a USB thumb drive and run a RAM disk. It is worth it to look at your electric bill to find how much you pay for power. Here I'm at $0.21 per KWH. A full size PC server can use 250W or more. There are 8760 hours in a year so you get $460 per year to run that 250W PC. The little Atom will pay for itself in just a few months. The first time I did that calculation, my power hogs where given away. On Sun, Aug 19, 2012 at 7:42 AM, Stan, W1LE stanw...@verizon.net wrote: Hello The Net, For your consideration: The INTEL model DN2800mt ITX mother board uses a ATOM CPU and draws about 11 watts of AC power when configured as: (I have not measured DC power yet.) 30 GB OCZ Nocti mSATA solid state drive, WIN7 pro, 64 bit, USB keyboard and mouse APEX MI-0008 case. Also has: parallel port available on mother board, you extend to a connector RS232 serial port available on mother board, you extend to a connector a single DC power supply from 11 to 19 V DC. 1 each PCIe expansion port, I will use with a premium 4 channel sound card SATA ports available for HDD/SDD, USB ports are available, Motherboard sound, and Gigalan. I have not played with NTP, (yet), but it sounds like a decent time nut technical challenge. My application is for a remote site with only 13V DC power available from PV/batteries. Then use fiber ethernet to get off site. The INTEL website would have further details. Stan, W1LECape Cod FN41sr z ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Modern motherboard with RS232 port
Phase angle/power factor Don Tom Knox Hi Ed; I may not have had enough coffee yet, but if Volt X Amps = Watts why would there be a difference? Best Wishes; Thomas Knox Date: Sun, 19 Aug 2012 12:35:51 -0600 From: ed_pal...@sasktel.net To: time-nuts@febo.com Subject: Re: [time-nuts] Modern motherboard with RS232 port It's important to remember that on a computer, the wattage shown has no relationship to the wattage pulled from the socket. The numbers shown are maximum values. You have to measure the power draw and you have to measure it in volt-amps, not watts because that's how residential power is measured (at least in North America). Buy an energy meter that shows volt-amps. They're relatively cheap - typically less than $50. Ed On 8/19/2012 11:06 AM, Chris Albertson wrote: This sounds like a newer version of the board I use. The thing to check is if the CPU heat sink has a fan or not. Having no fan indicates that the CPU is not using much power. It also removes a common failure point. To reduce power even more. On an NTP server you can unplug the keyboard, mouse and monitor and if you have other servers on the LAN configure one as a boot server and have it run TFTP then your NTP server does not need a disk drive. It can run off a RAM disk. This makes it very fast, even faster than a SSD and it saves some cash. Makes backup easy too as there is nothing to backup if there is no local storage. If you don't have a TFTP server use a small notebook size disk drive. Even a 80GB drive is overkill. You can also boot from a USB thumb drive and run a RAM disk. It is worth it to look at your electric bill to find how much you pay for power. Here I'm at $0.21 per KWH. A full size PC server can use 250W or more. There are 8760 hours in a year so you get $460 per year to run that 250W PC. The little Atom will pay for itself in just a few months. The first time I did that calculation, my power hogs where given away. On Sun, Aug 19, 2012 at 7:42 AM, Stan, W1LE stanw...@verizon.net wrote: Hello The Net, For your consideration: The INTEL model DN2800mt ITX mother board uses a ATOM CPU and draws about 11 watts of AC power when configured as: (I have not measured DC power yet.) 30 GB OCZ Nocti mSATA solid state drive, WIN7 pro, 64 bit, USB keyboard and mouse APEX MI-0008 case. Also has: parallel port available on mother board, you extend to a connector RS232 serial port available on mother board, you extend to a connector a single DC power supply from 11 to 19 V DC. 1 each PCIe expansion port, I will use with a premium 4 channel sound card SATA ports available for HDD/SDD, USB ports are available, Motherboard sound, and Gigalan. I have not played with NTP, (yet), but it sounds like a decent time nut technical challenge. My application is for a remote site with only 13V DC power available from PV/batteries. Then use fiber ethernet to get off site. The INTEL website would have further details. Stan, W1LECape Cod FN41sr z ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. -- Neither the voice of authority nor the weight of reason and argument are as significant as experiment, for thence comes quiet to the mind. R. Bacon If you don't know what it is, don't poke it. Ghost in the Shell Dr. Don Latham AJ7LL Six Mile Systems LLP 17850 Six Mile Road POB 134 Huson, MT, 59846 VOX 406-626-4304 www.lightningforensics.com www.sixmilesystems.com ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Modern motherboard with RS232 port
On 08/19/2012 03:38 PM, Christopher Brown wrote: Though I am a little surprised about residential power being measured/billed in VA not KW/h in North America. Pretty sure the US is in North America, even Alaska in slightly more North America. Never seen a VA/h meter in the US. Was guessing it was a CA thing, even though I had never run across any mention of VA billing in CA, but am looking at Manitoba Hydro, NB power and SaskPower billing rates right now in KW/h. Ed, can you chime in here, where is power billed by VA (outside of some commercial/industrial and private generation agreements)? VA is used all over the place in electrical systems calculations and equipment specs but have never seen billing on it. It's also my understanding that homes are always billed by the watt. Even in industrial scale they charge a fee for poor power factor but they aren't billing by VA, according to Wikipedia at least. Still, a good plug-in power meter is a great tool for any home. I would have one already but everything is already plugged into a battery backup with a watt-meter built in and I'm not terribly concerned about accuracy. -- m. tharp ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Modern motherboard with RS232 port
Is it just me, or has this thread gone off topic a tad ?? 73, Dick, W1KSZ -Original Message- From: Michael Tharp g...@partiallystapled.com Sent: Aug 19, 2012 12:42 PM To: time-nuts@febo.com Subject: Re: [time-nuts] Modern motherboard with RS232 port On 08/19/2012 03:38 PM, Christopher Brown wrote: Though I am a little surprised about residential power being measured/billed in VA not KW/h in North America. Pretty sure the US is in North America, even Alaska in slightly more North America. Never seen a VA/h meter in the US. Was guessing it was a CA thing, even though I had never run across any mention of VA billing in CA, but am looking at Manitoba Hydro, NB power and SaskPower billing rates right now in KW/h. Ed, can you chime in here, where is power billed by VA (outside of some commercial/industrial and private generation agreements)? VA is used all over the place in electrical systems calculations and equipment specs but have never seen billing on it. It's also my understanding that homes are always billed by the watt. Even in industrial scale they charge a fee for poor power factor but they aren't billing by VA, according to Wikipedia at least. Still, a good plug-in power meter is a great tool for any home. I would have one already but everything is already plugged into a battery backup with a watt-meter built in and I'm not terribly concerned about accuracy. -- m. tharp ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Modern motherboard with RS232 port
No it is not. VA * PF = W for VA = volt amps, PF = power factor, W = watts (or true power) PF = the cos of the phase angle between the current and the voltage (assuming both are sine waves) + Peak Volts * 0.707 = RMS volts, again for sine waves only. + - Original Message - From: Christopher Brown cbr...@woods.net To: time-nuts@febo.com Sent: Sunday, August 19, 2012 3:38 PM Subject: Re: [time-nuts] Modern motherboard with RS232 port Converting VA to W is same as converting peak V to RMS V. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Modern motherboard with RS232 port
Cosine of the phase angle is the power factor, a number between 0 and 1 But only for sine waves. - Original Message - From: jmfranke jmfra...@cox.net To: Time-Nuts time-nuts@febo.com Sent: Sunday, August 19, 2012 3:36 PM Subject: Re: [time-nuts] Modern motherboard with RS232 port There is no difference for a resistive load. For a reactive load, you have to take in account the phase angle between the current and the voltage. If I remember correctly, power = Volts X Amps X cosine of the phase angle. Some refer to the phase angle as the power factor. John WA4WDL -- From: Tom Knox act...@hotmail.com Sent: Sunday, August 19, 2012 3:19 PM To: Time-Nuts time-nuts@febo.com Subject: Re: [time-nuts] Modern motherboard with RS232 port Hi Ed; I may not have had enough coffee yet, but if Volt X Amps = Watts why would there be a difference? Best Wishes; Thomas Knox Date: Sun, 19 Aug 2012 12:35:51 -0600 From: ed_pal...@sasktel.net To: time-nuts@febo.com Subject: Re: [time-nuts] Modern motherboard with RS232 port It's important to remember that on a computer, the wattage shown has no relationship to the wattage pulled from the socket. The numbers shown are maximum values. You have to measure the power draw and you have to measure it in volt-amps, not watts because that's how residential power is measured (at least in North America). Buy an energy meter that shows volt-amps. They're relatively cheap - typically less than $50. Ed On 8/19/2012 11:06 AM, Chris Albertson wrote: This sounds like a newer version of the board I use. The thing to check is if the CPU heat sink has a fan or not. Having no fan indicates that the CPU is not using much power. It also removes a common failure point. To reduce power even more. On an NTP server you can unplug the keyboard, mouse and monitor and if you have other servers on the LAN configure one as a boot server and have it run TFTP then your NTP server does not need a disk drive. It can run off a RAM disk. This makes it very fast, even faster than a SSD and it saves some cash. Makes backup easy too as there is nothing to backup if there is no local storage. If you don't have a TFTP server use a small notebook size disk drive. Even a 80GB drive is overkill. You can also boot from a USB thumb drive and run a RAM disk. It is worth it to look at your electric bill to find how much you pay for power. Here I'm at $0.21 per KWH. A full size PC server can use 250W or more. There are 8760 hours in a year so you get $460 per year to run that 250W PC. The little Atom will pay for itself in just a few months. The first time I did that calculation, my power hogs where given away. On Sun, Aug 19, 2012 at 7:42 AM, Stan, W1LE stanw...@verizon.net wrote: Hello The Net, For your consideration: The INTEL model DN2800mt ITX mother board uses a ATOM CPU and draws about 11 watts of AC power when configured as: (I have not measured DC power yet.) 30 GB OCZ Nocti mSATA solid state drive, WIN7 pro, 64 bit, USB keyboard and mouse APEX MI-0008 case. Also has: parallel port available on mother board, you extend to a connector RS232 serial port available on mother board, you extend to a connector a single DC power supply from 11 to 19 V DC. 1 each PCIe expansion port, I will use with a premium 4 channel sound card SATA ports available for HDD/SDD, USB ports are available, Motherboard sound, and Gigalan. I have not played with NTP, (yet), but it sounds like a decent time nut technical challenge. My application is for a remote site with only 13V DC power available from PV/batteries. Then use fiber ethernet to get off site. The INTEL website would have further details. Stan, W1LECape Cod FN41sr z ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Modern motherboard with RS232 port
I stand corrected, shows what I get for listening to a UPS vendors documentation. On 8/19/12 11:52 AM, Tom Miller wrote: No it is not. VA * PF = W for VA = volt amps, PF = power factor, W = watts (or true power) PF = the cos of the phase angle between the current and the voltage (assuming both are sine waves) + Peak Volts * 0.707 = RMS volts, again for sine waves only. + - Original Message - From: Christopher Brown cbr...@woods.net To: time-nuts@febo.com Sent: Sunday, August 19, 2012 3:38 PM Subject: Re: [time-nuts] Modern motherboard with RS232 port Converting VA to W is same as converting peak V to RMS V. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Modern motherboard with RS232 port
ed_pal...@sasktel.net said: You have to measure the power draw and you have to measure it in volt-amps, not watts because that's how residential power is measured (at least in North America). Are you sure about that? I've never seen that claim before. Here is PGE's blurb that covers their residential rates: http://www.pge.com/tariffs/tm2/pdf/ELEC_RULES_2.pdf I didn't find a section that says we bill by watts not VA. I did find a section that discusses tariffs based on horsepower vs watts and it mentioned volt-amps. They clearly know about the difference. My bill says Kwh not Kvah. act...@hotmail.com said: I may not have had enough coffee yet, but if Volt X Amps = Watts why would there be a difference? The magic word is power factor. In AC, the power is volts*amps*cos(angle). http://en.wikipedia.org/wiki/Power_factor Consider an inductor. The voltage and current are 90 degrees out of phase. Half the time, one of them has the wrong sign. Sometimes you are putting energy into the magnetic field. Sometimes the field is putting power back into the line. -- These are my opinions. I hate spam. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Modern motherboard with RS232 port
In message 503141b7.6070...@partiallystapled.com, Michael Tharp writes: On 08/19/2012 03:38 PM, Christopher Brown wrote: VA is used all over the place in electrical systems calculations and equipment specs but have never seen billing on it. Billing VA is usually a kWh price and a KVAR surcharge. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-tahoe Never attribute to malice what can adequately be explained by incompetence. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Modern motherboard with RS232 port
On Sun, Aug 19, 2012 at 12:19 PM, Tom Knox act...@hotmail.com wrote: Hi Ed; I may not have had enough coffee yet, but if Volt X Amps = Watts why would there be a difference? That relationship holds for DC but with AC the phase relationship between voltage and current depends of the complex impedance of the load.If the load is reactive the phase will not be exactly 90 degrees. When we do the math inour heads most of us always simplify and don't bother with complex numbers but in real life impedance is complex. But for simple back of envelope calculations we can pretend the power is DC and just say Volt X Amps = Watts Another simple way to know if your PC is going to cost you an arm and a leg to run 24x7 is to place your hand over the cooling fan exhaust vent if hot air is coming out you can know for sure that you are paying $$$ to heat that air Even if the PC consumes only 50W that works out to 438 KWH per year at 20 cents per KWH you can still pay for a new $100 Atom motherboard with the savings in power and see a profit 2 years. If gets worse in the summer if you need to run the AC. Let's say the PC burns 1W. That dumps 1W of heat into the building and if your air conditioning runs on a thermostat it will burn a little over 1W to remove the extra heat. The AC is a multiplier of the power used in the house. Using this logic someone at work figured out it was cost effective to trash very old CRT monitor in the building. Same for the light bulbs, we pay a lot to cool the lighting load. (I would have simply installed windows that open and saved even more money.) -- Chris Albertson Redondo Beach, California ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Modern motherboard with RS232 port
On Sun, Aug 19, 2012 at 1:16 PM, Chris Albertson albertson.ch...@gmail.comwrote: If the load is reactive the phase will not be exactly 90 degrees. The above is not what I meant. I meant voltage and current might not be in phase and might even be 90 out of phase. Then you can see that each phase is multiplied by zero. Chris Albertson Redondo Beach, California ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Modern motherboard with RS232 port
I was afraid that this topic would turn into a swamp and I didn't help things by getting it backwards. Yes, the residential meter measures WattHours, not VoltAmpHours. My apologies for adding confusion to an already confusing topic. While new PCs may have power factor corrected power supplies, many of us at least consider reusing old PCs. The differences between watts and volt-amps are significant on these machines. I powered up an old Compaq 1 GHz P3 and found that it draws ~60 watts and ~92 VA. Both are much lower than the stated draw of 4 amps @ 110 V. It actually draws ~0.75A. My main computer is a Dell Precision 490 Workstation. It draws ~180W and ~180 VA so it has power factor correction. But the stated rating is 6 amps @ 110V while it only draws ~1.5 amps. Any difference between Watts and VoltAmps can become an issue when you deal with a UPS (Uninterruptible Power Supply). I would hope that an NTP server would be plugged into a UPS. Most UPSs have different ratings for Watts and VoltAmps. You need an accurate measurement of your load to size the UPS correctly. So my basic point is still valid. For computers, don't believe the values stated on the labels. Measure them first. Ed On 8/19/2012 1:38 PM, Christopher Brown wrote: IIRC... VA for AC is peak volts times amps, not RMS volts. The whole point of dealing with RMS being that it makes AC and DC equiv for purposes of V * A = W. Converting VA to W is same as converting peak V to RMS V. Though I am a little surprised about residential power being measured/billed in VA not KW/h in North America. Pretty sure the US is in North America, even Alaska in slightly more North America. Never seen a VA/h meter in the US. Was guessing it was a CA thing, even though I had never run across any mention of VA billing in CA, but am looking at Manitoba Hydro, NB power and SaskPower billing rates right now in KW/h. Ed, can you chime in here, where is power billed by VA (outside of some commercial/industrial and private generation agreements)? VA is used all over the place in electrical systems calculations and equipment specs but have never seen billing on it. On 8/19/12 11:19 AM, Tom Knox wrote: Hi Ed; I may not have had enough coffee yet, but if Volt X Amps = Watts why would there be a difference? Best Wishes; Thomas Knox Date: Sun, 19 Aug 2012 12:35:51 -0600 From:ed_pal...@sasktel.net To:time-nuts@febo.com Subject: Re: [time-nuts] Modern motherboard with RS232 port It's important to remember that on a computer, the wattage shown has no relationship to the wattage pulled from the socket. The numbers shown are maximum values. You have to measure the power draw and you have to measure it in volt-amps, not watts because that's how residential power is measured (at least in North America). Buy an energy meter that shows volt-amps. They're relatively cheap - typically less than $50. Ed On 8/19/2012 11:06 AM, Chris Albertson wrote: This sounds like a newer version of the board I use. The thing to check is if the CPU heat sink has a fan or not. Having no fan indicates that the CPU is not using much power. It also removes a common failure point. To reduce power even more. On an NTP server you can unplug the keyboard, mouse and monitor and if you have other servers on the LAN configure one as a boot server and have it run TFTP then your NTP server does not need a disk drive. It can run off a RAM disk. This makes it very fast, even faster than a SSD and it saves some cash. Makes backup easy too as there is nothing to backup if there is no local storage. If you don't have a TFTP server use a small notebook size disk drive. Even a 80GB drive is overkill. You can also boot from a USB thumb drive and run a RAM disk. It is worth it to look at your electric bill to find how much you pay for power. Here I'm at $0.21 per KWH. A full size PC server can use 250W or more. There are 8760 hours in a year so you get $460 per year to run that 250W PC. The little Atom will pay for itself in just a few months. The first time I did that calculation, my power hogs where given away. On Sun, Aug 19, 2012 at 7:42 AM, Stan, W1LEstanw...@verizon.net wrote: Hello The Net, For your consideration: The INTEL model DN2800mt ITX mother board uses a ATOM CPU and draws about 11 watts of AC power when configured as: (I have not measured DC power yet.) 30 GB OCZ Nocti mSATA solid state drive, WIN7 pro, 64 bit, USB keyboard and mouse APEX MI-0008 case. Also has: parallel port available on mother board, you extend to a connector RS232 serial port available on mother board, you extend to a connector a single DC power supply from 11 to 19 V DC. 1 each PCIe expansion port, I will use with a premium 4 channel sound card SATA ports available for HDD/SDD, USB ports are available, Motherboard sound, and Gigalan. I have not played with NTP, (yet), but it sounds like a decent time nut technical challenge. My application
Re: [time-nuts] Modern motherboard with RS232 port
Hi The pi doesn't have a conventional serial port. It does have a TTL serial on the 28 pin connector. There are also IRQ pins on the same connector. Since they go directly to the CPU chip, hardware latency should be pretty good. It should interface directly to a TTL output gps receiver like a LEA-6T. You probably would need to tune up a driver to get it to work. Since it's Linux, you should be able to get some sort of ntp running on it. AFIK there are no neat counters like on a 45xx board. You also don't have a well tuned ntp since it's LInux. Bob On Aug 19, 2012, at 1:31 PM, Chris Albertson albertson.ch...@gmail.com wrote: On Sun, Aug 19, 2012 at 10:16 AM, bownes bow...@gmail.com wrote: Why not just use a raspberry pi? Uses a whole 2w at idle. Ntp might bump that to 2.01. You certainly could run ntpd on that box. But I wonder how the PPS is supported in hardware? What is the standard deviation of interrupt latency on the DCD pin on the serial port. Perhaps some one who has a pi could measure this. All the data should be in the system log as each PPS is time stamped and written to the log. If the DCD pin is polled you are not going to get decent results. Maybe someone could read the PPS drive code. -- Chris Albertson Redondo Beach, California ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Modern motherboard with RS232 port
On Sun, Aug 19, 2012 at 5:21 PM, Bob Camp li...@rtty.us wrote: Hi The pi doesn't have a conventional serial port. It does have a TTL serial on the 28 pin connector. There are also IRQ pins on the same connector. Since they go directly to the CPU chip, hardware latency should be pretty good. Is there a PPS device driver on the version of Linux that runs on this board?In theory all you need is the interrupt pin and a high speed (usec or nanosec counter) counter that can be captured by the device driver. But even with this hardware has anyone written the device driver? I don't understand the comment about no well tuned ntp. Chris Albertson Redondo Beach, California ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Modern motherboard with RS232 port
Hi There has been a lot of work done on FreeBSD kernel timing and ntp. That and the work PHK has done on some of the drivers makes it a tough thing to beat. Since the pi is ARM hardware, a lot of the 386 specific work isn't going to apply to it. Still that's less of an issue than the USB to Ethernet connection on the pi. Bob On Aug 19, 2012, at 8:38 PM, Chris Albertson albertson.ch...@gmail.com wrote: On Sun, Aug 19, 2012 at 5:21 PM, Bob Camp li...@rtty.us wrote: Hi The pi doesn't have a conventional serial port. It does have a TTL serial on the 28 pin connector. There are also IRQ pins on the same connector. Since they go directly to the CPU chip, hardware latency should be pretty good. Is there a PPS device driver on the version of Linux that runs on this board?In theory all you need is the interrupt pin and a high speed (usec or nanosec counter) counter that can be captured by the device driver. But even with this hardware has anyone written the device driver? I don't understand the comment about no well tuned ntp. Chris Albertson Redondo Beach, California ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Modern motherboard with RS232 port
It comes w ntp out of the box if you run fedora. On Aug 19, 2012, at 20:21, Bob Camp li...@rtty.us wrote: Hi The pi doesn't have a conventional serial port. It does have a TTL serial on the 28 pin connector. There are also IRQ pins on the same connector. Since they go directly to the CPU chip, hardware latency should be pretty good. It should interface directly to a TTL output gps receiver like a LEA-6T. You probably would need to tune up a driver to get it to work. Since it's Linux, you should be able to get some sort of ntp running on it. AFIK there are no neat counters like on a 45xx board. You also don't have a well tuned ntp since it's LInux. Bob On Aug 19, 2012, at 1:31 PM, Chris Albertson albertson.ch...@gmail.com wrote: On Sun, Aug 19, 2012 at 10:16 AM, bownes bow...@gmail.com wrote: Why not just use a raspberry pi? Uses a whole 2w at idle. Ntp might bump that to 2.01. You certainly could run ntpd on that box. But I wonder how the PPS is supported in hardware? What is the standard deviation of interrupt latency on the DCD pin on the serial port. Perhaps some one who has a pi could measure this. All the data should be in the system log as each PPS is time stamped and written to the log. If the DCD pin is polled you are not going to get decent results. Maybe someone could read the PPS drive code. -- Chris Albertson Redondo Beach, California ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Modern motherboard with RS232 port
Hi But you still need: 1) Porting of the kernel timing stuff to the ARM6 architecture. Once it's ported, you need it debugged and fine tuned. 2) The low level drivers in NTP ported to the ARM6 i/o setup. They also need some work to reduce latency. 3) The timing work on the USB to Ethernet interface. I'm not knocking the pi, it's a fine little gizmo. However it's just that, a little gizmo, at this point. There's still a lot of work to be done on it. Getting a solid implementation of anything takes significant work. There are other reasonably cheap / low power platforms where people have already put in the man years to ring things out. Bob On Aug 19, 2012, at 9:49 PM, bownes bow...@gmail.com wrote: It comes w ntp out of the box if you run fedora. On Aug 19, 2012, at 20:21, Bob Camp li...@rtty.us wrote: Hi The pi doesn't have a conventional serial port. It does have a TTL serial on the 28 pin connector. There are also IRQ pins on the same connector. Since they go directly to the CPU chip, hardware latency should be pretty good. It should interface directly to a TTL output gps receiver like a LEA-6T. You probably would need to tune up a driver to get it to work. Since it's Linux, you should be able to get some sort of ntp running on it. AFIK there are no neat counters like on a 45xx board. You also don't have a well tuned ntp since it's LInux. Bob On Aug 19, 2012, at 1:31 PM, Chris Albertson albertson.ch...@gmail.com wrote: On Sun, Aug 19, 2012 at 10:16 AM, bownes bow...@gmail.com wrote: Why not just use a raspberry pi? Uses a whole 2w at idle. Ntp might bump that to 2.01. You certainly could run ntpd on that box. But I wonder how the PPS is supported in hardware? What is the standard deviation of interrupt latency on the DCD pin on the serial port. Perhaps some one who has a pi could measure this. All the data should be in the system log as each PPS is time stamped and written to the log. If the DCD pin is polled you are not going to get decent results. Maybe someone could read the PPS drive code. -- Chris Albertson Redondo Beach, California ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Modern motherboard with RS232 port
On Sun, Aug 19, 2012 at 6:49 PM, bownes bow...@gmail.com wrote: It comes w ntp out of the box if you run fedora. You can run NTP without a Pulse Per Second (PPS) driver. It will work just fine. Most NTP installations don't use PPS. But if you want to connect a GPS receiver and use it for precision timing you must have PPS support. So having a working NTP out of the box is not enough. Chris Albertson Redondo Beach, California ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Modern motherboard with RS232 port
Residential power is traditionally measured in watts, not V-A. Commercial power is typically measured in V-A, with an additional fee for power factor problems. -Chuck Harris Ed Palmer wrote: It's important to remember that on a computer, the wattage shown has no relationship to the wattage pulled from the socket. The numbers shown are maximum values. You have to measure the power draw and you have to measure it in volt-amps, not watts because that's how residential power is measured (at least in North America). Buy an energy meter that shows volt-amps. They're relatively cheap - typically less than $50. Ed ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Modern motherboard with RS232 port
The long and the short of it is that when AC encounters a reactive load, it results in a current that is not in phase with the voltage. Power is equal to volts x amps only when the current and voltage are in phase which can only happen if the load is purely resistive. If you hang a perfect capacitor across the power line, or a perfect inductor, you will draw lots of current, but no power. -Chuck Harris Tom Knox wrote: Hi Ed; I may not have had enough coffee yet, but if Volt X Amps = Watts why would there be a difference? Best Wishes; Thomas Knox ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Modern motherboard with RS232 port
Agreed. Just pointing out there isn't a big porting effort to get ntpd itself up and running. On Aug 19, 2012, at 22:24, Chris Albertson albertson.ch...@gmail.com wrote: On Sun, Aug 19, 2012 at 6:49 PM, bownes bow...@gmail.com wrote: It comes w ntp out of the box if you run fedora. You can run NTP without a Pulse Per Second (PPS) driver. It will work just fine. Most NTP installations don't use PPS. But if you want to connect a GPS receiver and use it for precision timing you must have PPS support. So having a working NTP out of the box is not enough. Chris Albertson Redondo Beach, California ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Modern motherboard with RS232 port
On 8/19/12 7:26 PM, Chuck Harris wrote: Residential power is traditionally measured in watts, not V-A. Commercial power is typically measured in V-A, with an additional fee for power factor problems. residential meters measure watts (active power) not VA... What you want is the Kill-A-Watt.. a $30 widget that measures all the parameters.. A great little deviec. -Chuck Harris Ed Palmer wrote: It's important to remember that on a computer, the wattage shown has no relationship to the wattage pulled from the socket. The numbers shown are maximum values. You have to measure the power draw and you have to measure it in volt-amps, not watts because that's how residential power is measured (at least in North America). Buy an energy meter that shows volt-amps. They're relatively cheap - typically less than $50. Ed ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
