Re: [RE-wrenches] Voltage discrepancy
Not sure if it's already been brought up or not.. but you might want to recheck all connections.. just to eliminate that issue.. dbDan BrownFoxfire Energy Corp.Renewable Energy Systems(802)-483-2564www.Foxfire-Energy.comNABCEP #092907-44 Original Message Subject: Re: [RE-wrenches] Voltage discrepancy From: boB Gudgel b...@midnitesolar.com Date: Thu, August 19, 2010 8:09 pm To: RE-wrenches re-wrenches@lists.re-wrenches.org Jeff Oldham wrote: I have seen this on my last 3 MX60 controllers and it is very frustrating and looks to be a design flaw. I can calibrate the meters to be accurate at either the Absorb point OR the Float point but NOT both!! Not only that but the meter calibrations tend to drift a bit in just a matter of days, just .1V not a big deal but anymore than that on a 12V sealed battery and it could be an issue. I spoke w/Outback about this and heard a mumbled "Ahh, uummm, yeah that is an issue". I'm guessing that you're seeing the same thing and when you spoke w/your customer again and the meters all agreed I'll bet it is because the MX was at the "line up point" of the other meters (just like a broken clock being correct twice a day!). The only way to live with this is to get the more important Absorb set point right on and take what you get on the lower end. It works and is usable but drives customers nuts when they have additional meters. In my experience the Tri-mets are dead on. Jeff, what size wire from charge controller to the battery are you using ?? The bigger the wire, the less the I*R drop and the less the voltage discrepancy ~should~ be, at higher currents. boB From the Solar, Wind and Hydro powered office of Jeff Oldham/Regenerative SOLutions *Notre Dame Certificates* 100% Online Programs in Negotiation Leadership and Mgmt. Enroll Today! http://thirdpartyoffers.juno.com/TGL3132/4c6dba9db492581fb20st02vucNotreDameOnline.com http://thirdpartyoffers.juno.com/TGL3132/4c6dba9db492581fb20st02vuc; ___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Options settings: http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org List-Archive: http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org List rules etiquette: www.re-wrenches.org/etiquette.htm Check out participant bios: www.members.re-wrenches.org ___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Options settings: http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org List-Archive: http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org List rules etiquette: www.re-wrenches.org/etiquette.htm Check out participant bios: www.members.re-wrenches.org ___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Options settings: http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org List-Archive: http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org List rules etiquette: www.re-wrenches.org/etiquette.htm Check out participant bios: www.members.re-wrenches.org
Re: [RE-wrenches] Voltage discrepancy
Bob you know the architecture of the MX60 is it a design problem or is it a component problem, I have not noticed this problem in older MX60s but I was not looking for it either. I have been able to adjust the meter and I typically would not check it again. I use my meter and adjust the MX60 to read the same. Again did Outback change suppliers? or was this problem always there? Darryl --- On Thu, 8/19/10, boB Gudgel b...@midnitesolar.com wrote: ___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Options settings: http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org List-Archive: http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org List rules etiquette: www.re-wrenches.org/etiquette.htm Check out participant bios: www.members.re-wrenches.org
Re: [RE-wrenches] Voltage discrepancy
Wire gauge isn't the only consideration. Check all crimps and connections in the DC path. A bad one can cause more drop than the wire. Dan --- On Fri, 8/20/10, Jeff Oldham starpowe...@juno.com wrote: From: Jeff Oldham starpowe...@juno.com Subject: Re: [RE-wrenches] Voltage discrepancy To: re-wrenches@lists.re-wrenches.org Date: Friday, August 20, 2010, 3:43 PM boB - it is 4' of #6 CU. and the charge rate averages 45A @ 12V nom. I understand that the Vd diff. from 13.6V @ 15A and 14.2V @45A is .1V but the meters when set nuts on at 14.2V are off by at least .3V @ 13.6V. This is not wire sizing issues nor does that explain the calibration drift over a few days. From the Solar, Wind and Hydro powered office of Jeff Oldham/Regenerative SOLutions ___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Options settings: http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org List-Archive: http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org List rules etiquette: www.re-wrenches.org/etiquette.htm Check out participant bios: www.members.re-wrenches.org
Re: [RE-wrenches] Voltage discrepancy
Correction: it is number 6 to the charge control, and 3/0 or 4/0 to the batteries. At 09:40 AM 8/20/2010, you wrote: boB, It looks like 3/0 or 4/0. It is a short run. At 08:09 PM 8/19/2010, you wrote: Jeff Oldham wrote: I have seen this on my last 3 MX60 controllers and it is very frustrating and looks to be a design flaw. I can calibrate the meters to be accurate at either the Absorb point OR the Float point but NOT both!! Not only that but the meter calibrations tend to drift a bit in just a matter of days, just .1V not a big deal but anymore than that on a 12V sealed battery and it could be an issue. I spoke w/Outback about this and heard a mumbled Ahh, uummm, yeah that is an issue. I'm guessing that you're seeing the same thing and when you spoke w/your customer again and the meters all agreed I'll bet it is because the MX was at the line up point of the other meters (just like a broken clock being correct twice a day!). The only way to live with this is to get the more important Absorb set point right on and take what you get on the lower end. It works and is usable but drives customers nuts when they have additional meters. In my experience the Tri-mets are dead on. Jeff, what size wire from charge controller to the battery are you using ?? The bigger the wire, the less the I*R drop and the less the voltage discrepancy ~should~ be, at higher currents. boB From the Solar, Wind and Hydro powered office of Jeff Oldham/Regenerative SOLutions *Notre Dame Certificates* 100% Online Programs in Negotiation Leadership and Mgmt. Enroll Today! http://thirdpartyoffers.juno.com/TGL3132/4c6dba9db492581fb20st02vucNotreDameOnline.com http://thirdpartyoffers.juno.com/TGL3132/4c6dba9db492581fb20st02vuc ___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Options settings: http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org List-Archive: http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org List rules etiquette: www.re-wrenches.org/etiquette.htm Check out participant bios: www.members.re-wrenches.org ___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Options settings: http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org List-Archive: http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org List rules etiquette: www.re-wrenches.org/etiquette.htm Check out participant bios: www.members.re-wrenches.org Drake Chamberlin Athens Electric OH License 44810 CO License 3773 NABCEP TM Certified PV Installer Office - 740-448-7328 Mobile - 740-856-9648 ___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Options settings: http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org List-Archive: http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org List rules etiquette: www.re-wrenches.org/etiquette.htm Check out participant bios: www.members.re-wrenches.org Drake Chamberlin Athens Electric OH License 44810 CO License 3773 NABCEP TM Certified PV Installer Office - 740-448-7328 Mobile - 740-856-9648 ___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Options settings: http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org List-Archive: http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org List rules etiquette: www.re-wrenches.org/etiquette.htm Check out participant bios: www.members.re-wrenches.org
Re: [RE-wrenches] Voltage discrepancy
I have seen this on my last 3 MX60 controllers and it is very frustrating and looks to be a design flaw. I can calibrate the meters to be accurate at either the Absorb point OR the Float point but NOT both!! Not only that but the meter calibrations tend to drift a bit in just a matter of days, just .1V not a big deal but anymore than that on a 12V sealed battery and it could be an issue. I spoke w/Outback about this and heard a mumbled Ahh, uummm, yeah that is an issue. I'm guessing that you're seeing the same thing and when you spoke w/your customer again and the meters all agreed I'll bet it is because the MX was at the line up point of the other meters (just like a broken clock being correct twice a day!). The only way to live with this is to get the more important Absorb set point right on and take what you get on the lower end. It works and is usable but drives customers nuts when they have additional meters. In my experience the Tri-mets are dead on. From the Solar, Wind and Hydro powered office of Jeff Oldham/Regenerative SOLutions Notre Dame Certificates 100% Online Programs in Negotiation Leadership and Mgmt. Enroll Today! http://thirdpartyoffers.juno.com/TGL3131/4c6dba9db492581fb20st02vuc___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Options settings: http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org List-Archive: http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org List rules etiquette: www.re-wrenches.org/etiquette.htm Check out participant bios: www.members.re-wrenches.org
Re: [RE-wrenches] Voltage discrepancy
Jeff Oldham wrote: I have seen this on my last 3 MX60 controllers and it is very frustrating and looks to be a design flaw. I can calibrate the meters to be accurate at either the Absorb point OR the Float point but NOT both!! Not only that but the meter calibrations tend to drift a bit in just a matter of days, just .1V not a big deal but anymore than that on a 12V sealed battery and it could be an issue. I spoke w/Outback about this and heard a mumbled Ahh, uummm, yeah that is an issue. I'm guessing that you're seeing the same thing and when you spoke w/your customer again and the meters all agreed I'll bet it is because the MX was at the line up point of the other meters (just like a broken clock being correct twice a day!). The only way to live with this is to get the more important Absorb set point right on and take what you get on the lower end. It works and is usable but drives customers nuts when they have additional meters. In my experience the Tri-mets are dead on. Jeff, what size wire from charge controller to the battery are you using ?? The bigger the wire, the less the I*R drop and the less the voltage discrepancy ~should~ be, at higher currents. boB From the Solar, Wind and Hydro powered office of Jeff Oldham/Regenerative SOLutions *Notre Dame Certificates* 100% Online Programs in Negotiation Leadership and Mgmt. Enroll Today! http://thirdpartyoffers.juno.com/TGL3132/4c6dba9db492581fb20st02vucNotreDameOnline.com http://thirdpartyoffers.juno.com/TGL3132/4c6dba9db492581fb20st02vuc ___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Options settings: http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org List-Archive: http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org List rules etiquette: www.re-wrenches.org/etiquette.htm Check out participant bios: www.members.re-wrenches.org ___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Options settings: http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org List-Archive: http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org List rules etiquette: www.re-wrenches.org/etiquette.htm Check out participant bios: www.members.re-wrenches.org
Re: [RE-wrenches] Voltage discrepancy
Thanks Jeff, That could be the explanation. Outback has metering issues with the Mate too. When I talked to a tech support about he fact that the Mate on my system seemed woefully inaccurate, she chuckled and affirmed that the were pretty approximate. -Drake At 07:12 PM 8/19/2010, you wrote: I have seen this on my last 3 MX60 controllers and it is very frustrating and looks to be a design flaw. I can calibrate the meters to be accurate at either the Absorb point OR the Float point but NOT both!! Not only that but the meter calibrations tend to drift a bit in just a matter of days, just .1V not a big deal but anymore than that on a 12V sealed battery and it could be an issue. I spoke w/Outback about this and heard a mumbled Ahh, uummm, yeah that is an issue. I'm guessing that you're seeing the same thing and when you spoke w/your customer again and the meters all agreed I'll bet it is because the MX was at the line up point of the other meters (just like a broken clock being correct twice a day!). The only way to live with this is to get the more important Absorb set point right on and take what you get on the lower end. It works and is usable but drives customers nuts when they have additional meters. In my experience the Tri-mets are dead on. Drake Chamberlin Athens Electric OH License 44810 CO License 3773 NABCEP TM Certified PV Installer Office - 740-448-7328 Mobile - 740-856-9648 ___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Options settings: http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org List-Archive: http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org List rules etiquette: www.re-wrenches.org/etiquette.htm Check out participant bios: www.members.re-wrenches.org
Re: [RE-wrenches] Voltage discrepancy
Drake, --- You wrote: I called her back just now, and the voltage readings on the Mate, MX and Trimetric all match. Humm. The batteries are 4, 4 1/2 year old, U.S. Battery L-16s wired in 24 volt configuration. It seems that I remember postings of Wrenches having problems with these batteries. There is about 1 KW STC of PV on the roof. --- end of quote --- Is there any chance she initially read the array voltage on the MX60 instead of the battery voltage? Both numbers are displayed simultaneously, of course. This is a relatively small battery bank. Could it be getting tired, somewhat prematurely? Charge rate is right up there, ~C/8. Tired battery + high charge rate = lots of H20? Dick Ratico Solarwind Electric Bradford,VT ___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Options settings: http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org List-Archive: http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org List rules etiquette: www.re-wrenches.org/etiquette.htm Check out participant bios: www.members.re-wrenches.org
[RE-wrenches] Voltage discrepancy
Hello Wrenches, I just got off the phone with an off grid system owner who has a voltage discrepancy showing between the reading on her MX-60 and both her Mate and Trimetric meter. The MX-60 shows 28.8 V and the Trimetric and the Mate both show around 25 volts. The batteries are using a tremendous amount of water. Has anyone seen this scenario before? Do you think the MX-60 is bad? Thanks, Drake Chamberlin Athens Electric OH License 44810 CO License 3773 NABCEP TM Certified PV Installer Office - 740-448-7328 Mobile - 740-856-9648 ___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Options settings: http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org List-Archive: http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org List rules etiquette: www.re-wrenches.org/etiquette.htm Check out participant bios: www.members.re-wrenches.org
Re: [RE-wrenches] Voltage discrepancy
Drake, I'd start by having her disconnect the temp sensor. If it has failed, it can cause false voltage compensation. However, if the MX60 is reading higher than actual, as your post suggests, I would more expect it to regulate sooner, thus leading to less water consumption, not more. Allan Allan Sindelar Allan@positiveenergysolar.com NABCEP Certified Photovoltaic Installer EE98J Journeyman Electrician Positive Energy, Inc. 3201 Calle Marie Santa Fe, New Mexico 87507 505 424-1112 www.positiveenergysolar.com On 8/14/2010 7:58 AM, Drake Chamberlin wrote: Hello Wrenches, I just got off the phone with an off grid system owner who has a voltage discrepancy showing between the reading on her MX-60 and both her Mate and Trimetric meter. The MX-60 shows 28.8 V and the Trimetric and the Mate both show around 25 volts. The batteries are using a tremendous amount of water. Has anyone seen this scenario before? Do you think the MX-60 is bad? Thanks, Drake Chamberlin Athens Electric OH License 44810 CO License 3773 NABCEP TM Certified PV Installer Office - 740-448-7328 Mobile - 740-856-9648 ___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Options settings: http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org List-Archive: http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org List rules etiquette: www.re-wrenches.org/etiquette.htm Check out participant bios: www.members.re-wrenches.org ___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Options settings: http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org List-Archive: http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org List rules etiquette: www.re-wrenches.org/etiquette.htm Check out participant bios: www.members.re-wrenches.org
