Re: [RE-wrenches] Off-grid non-inverter battery charger recommendations?
Through a strange set of circumstances, I found a way to equalize batteries with an Iota charger. My DLS 45 was borrowed on a couple of occasions. I made the mistake of telling the borrowers how to adjust the voltage through the potentiometer. Predictably, when I needed the unit, the pot had been ruined. Calling Iota, they said there was no fix. The pot was soldered to the board. The way the device works is that lowering the pot resistance increases the output voltage. My solution was to cut the pot out of the circuit board and solder the leads together. Now with the quick charge plug out, it holds at 15.2 to 15.4 volts. The the quick charge plug in, it runs at around 15.7 volts. I equalized a pair of T-105s yesterday without the quick charge plug. It worked like a charm. This is much more useful for my needs than the factory configuration. My uses are emergency charges from generators, often in cold weather, and equalization charges. The operation of removing the pot was tricky for me, but someone more used to working with electronic circuit boards might not find it too difficult. At 01:27 PM 10/15/2012, you wrote: Hi, Mechanix~ Bill Dorsett polled the group about recommended battery chargers for connection to a generator. Iota brand is the successor to Todd brand; I believe Iota bought the designs, tooling, etc. and these have appeal because of the relatively low cost per rated amp. They seem generator tolerant. The Todd design is a constant voltage type charger, however--basically an AC to DC converter with a fixed voltage output. In my experience, the 75 amp Todd type charger will deliver 75 amps only for a relatively short time when first connected to a low battery. As the battery's voltage comes up that presents a sort of back pressure which slows the rate of charge. That's not so bad if one has utility power always on to drive the charger, but if an engine generator is running... The inverter/chargers (with which we are all familiar) begin with a constant current part of the charge cycle--aka bulk charge. The charger is determined to sock the battery with the amperage we have requested in the setup; I think a pulse width modulation is going on where the charger hums up its voltage in order to keep the amps high even as the back pressure builds. When it's time for the absorption phase of the charge, the logic shifts to a constant voltage where the amps are gradually dialed lower in order to keep the battery at the target voltage so it can absorb. Ignoring the float phase which would come later, this overall charge regimen would be called CC/CV for constant current/constant voltage. The CV part of that is not much different from what a Todd style charger does; it's just that the Todd design does not precede that phase with a CC constant current phase. Some free-standing battery chargers have a CC/CV algorithm but those seem to cost as much or more than a comparably rated inverter/charger. Check the Magnum mod-square multi's, Bill, such as their RD series. As others on this List have noted, just the charge function is pretty good and since the inverter circuit is not pure sine, that keeps the cost lower. Built in time delay before it loads up the generator is an added benefit. Jolliness, Mick Abraham, Proprietor http://www.abrahamsolar.comwww.abrahamsolar.com Voice: 970-731-4675 ___ 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] Off-grid non-inverter battery charger recommendations?
Hi Drake,Good find. We always adjust the Iota's for different types of batteries. Since this one is only used for back up purposes with a generator, you can leave the jumper in and always run at 15.7 volts. Once the voltage reaches that point, you will be +/-90% charged. This will not harm a flooded battery. If the converter is used long term with shore power, I would recommend that you install a resistor where you soldered the leads together to drop the voltage back to about 14.2vdc to preserve battery life. Also add a switch in parallel with the resistor and you will have the ability to select 14.2, 14.8 (jumper in) or 15.7 volts.Larry CrutcherStarlight Solar Power Systems Original Message Subject: Re: [RE-wrenches] Off-grid non-inverter battery charger recommendations? From: Drake drake.chamber...@redwoodalliance.org Date: Fri, October 26, 2012 6:23 am To: RE-wrenches re-wrenches@lists.re-wrenches.org Through a strange set of circumstances, I found a way to equalize batteries with an Iota charger. My DLS 45 was borrowed on a couple of occasions. I made the mistake of telling the borrowers how to adjust the voltage through the potentiometer. Predictably, when I needed the unit, the pot had been ruined. Calling Iota, they said there was no fix. The pot was soldered to the board. The way the device works is that lowering the pot resistance increases the output voltage. My solution was to cut the pot out of the circuit board and solder the leads together. Now with the quick charge plug out, it holds at 15.2 to 15.4 volts. The the quick charge plug in, it runs at around 15.7 volts. I equalized a pair of T-105s yesterday without the quick charge plug. It worked like a charm. This is much more useful for my needs than the factory configuration. My uses are emergency charges from generators, often in cold weather, and equalization charges. The operation of removing the pot was tricky for me, but someone more used to working with electronic circuit boards might not find it too difficult. At 01:27 PM 10/15/2012, you wrote: Hi, Mechanix~ Bill Dorsett polled the group about recommended battery chargers for connection to a generator. Iota brand is the successor to Todd brand; I believe Iota bought the designs, tooling, etc. and these have appeal because of the relatively low cost per rated amp. They seem generator tolerant. The Todd design is a "constant voltage" type charger, however--basically an AC to DC converter with a fixed voltage output. In my experience, the "75 amp" Todd type charger will deliver 75 amps only for a relatively short time when first connected to a low battery. As the battery's voltage comes up that presents a sort of "back pressure" which slows the rate of charge. That's not so bad if one has utility power always on to drive the charger, but if an engine generator is running... The inverter/chargers (with which we are all familiar) begin with a "constant current" part of the charge cycle--aka bulk charge. The charger is determined to sock the battery with the amperage we have requested in the setup; I think a pulse width modulation is going on where the charger hums up its voltage in order to keep the amps high even as the back pressure builds. When it's time for the absorption phase of the charge, the logic shifts to a "constant voltage" where the amps are gradually dialed lower in order to keep the battery at the target voltage so it can "absorb". Ignoring the float phase which would come later, this overall charge regimen would be called CC/CV for "constant current/constant voltage". The CV part of that is not much different from what a Todd style charger does; it's just that the Todd design does not precede that phase with a CC "constant current" phase. Some free-standing battery chargers have a CC/CV algorithm but those seem to cost as much or more than a comparably rated inverter/charger. Check the Magnum mod-square multi's, Bill, such as their RD series. As others on this List have noted, just the charge function is pretty good and since the inverter circuit is not pure sine, that keeps the cost lower. Built in time delay before it loads up the generator is an added benefit. Jolliness, Mick Abraham, Proprietor www.abrahamsolar.com Voice: 970-731-4675 ___ 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-w
Re: [RE-wrenches] Off-grid non-inverter battery charger recommendations?
Check out Iota. Aaron Mandelkorn NABCEP Certified PV Installer Renewable Energy Outfitters Box 65 Salida, CO. 81201 (970)596-3744 reoso...@gmail.com www.reosolar.com On Oct 15, 2012, at 9:14 AM, William Dorsett wrote: What brand recommendations do the group have for an battery charger to be plugged into a genset? Used to be Todd but at some point they lost favor. Thanks all. Bill Dorsett Sunwrights 1715 Leavenworth Manhattan, KS 785/539-1956 Home/Office ___ 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] Off-grid non-inverter battery charger recommendations?
You might also check Power Source Jay Peltz power Sent from my iPad On Oct 15, 2012, at 8:32 AM, Dan Fink danbo...@gmail.com wrote: We have had great luck with Iota. More reasonably priced than Xantrex, too, but not as many flashy lights. They also work great as 12VDC power supplies for ham radio shacks, etc. -- Dan Fink, Executive Director; Otherpower Buckville Energy Consulting Buckville Publications LLC NABCEP / IREC accredited Continuing Education Providers 970.672.4342 (voicemail) On Mon, Oct 15, 2012 at 9:14 AM, William Dorsett wmdors...@sbcglobal.net wrote: What brand recommendations do the group have for an battery charger to be plugged into a genset? Used to be Todd but at some point they lost favor. Thanks all. Bill Dorsett Sunwrights 1715 Leavenworth Manhattan, KS 785/539-1956 Home/Office ___ 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] Off-grid non-inverter battery charger recommendations?
Thanks Aaron, but I need one that goes to 15.5 or 16V for equalizing the bank. Just got this back from Iota: Iota does not make any chargers that go to 15 volts output for equalizing. Thank you Iota Engineering Xantrex TruCharge 20 at least has an equalize setting, though I don't know how adjustable it is. Bill Dorsett Sunwrights Manhattan, KS From: re-wrenches-boun...@lists.re-wrenches.org [mailto:re-wrenches-boun...@lists.re-wrenches.org] On Behalf Of Aaron Mandelkorn Sent: Monday, October 15, 2012 10:24 AM To: RE-wrenches Subject: Re: [RE-wrenches] Off-grid non-inverter battery charger recommendations? Check out Iota. Aaron Mandelkorn NABCEP Certified PV Installer Renewable Energy Outfitters Box 65 Salida, CO. 81201 (970)596-3744 reoso...@gmail.com www.reosolar.com On Oct 15, 2012, at 9:14 AM, William Dorsett wrote: What brand recommendations do the group have for an battery charger to be plugged into a genset? Used to be Todd but at some point they lost favor. Thanks all. Bill Dorsett Sunwrights 1715 Leavenworth Manhattan, KS 785/539-1956 Home/Office ___ 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] Off-grid non-inverter battery charger recommendations?
There is a potentiometer on the board of the IOTA chargers that used to be assessable through a hole in the cover. I adjusted a new one two weeks ago and had to open it up to get at the pot. Adjusts up 15.6VDC with plug in and 14.8 with the jumper plug out. Some of the older models would adjust up to 16.5V and the new ones may as well, I did not need that value with the last charger. These are very simple units that could be considered a fire hazard in the wrong place/hands. I use for the lowest of the low budgets that are way, way off-grid and always explain the caveat to not have flammable things anywhere close to it. I had a couple of Todds spark off a number of years ago. Caused some excitement. -Dave David Palumbo Independent Power LLC 462 Solar Way Drive Hyde Park, VT 05655 www.independentpowerllc.com NABCEP Certified PV Installer Vermont Solar Partner 24 Years Experience, (802) 888-7194 From: re-wrenches-boun...@lists.re-wrenches.org [mailto:re-wrenches-boun...@lists.re-wrenches.org] On Behalf Of William Dorsett Sent: Monday, October 15, 2012 2:27 PM To: 'RE-wrenches' Subject: Re: [RE-wrenches] Off-grid non-inverter battery charger recommendations? Thanks Aaron, but I need one that goes to 15.5 or 16V for equalizing the bank. Just got this back from Iota: Iota does not make any chargers that go to 15 volts output for equalizing. Thank you Iota Engineering Xantrex TruCharge 20 at least has an equalize setting, though I don't know how adjustable it is. Bill Dorsett Sunwrights Manhattan, KS From: re-wrenches-boun...@lists.re-wrenches.org [mailto:re-wrenches-boun...@lists.re-wrenches.org] On Behalf Of Aaron Mandelkorn Sent: Monday, October 15, 2012 10:24 AM To: RE-wrenches Subject: Re: [RE-wrenches] Off-grid non-inverter battery charger recommendations? Check out Iota. Aaron Mandelkorn NABCEP Certified PV Installer Renewable Energy Outfitters Box 65 Salida, CO. 81201 (970)596-3744 reoso...@gmail.com www.reosolar.com On Oct 15, 2012, at 9:14 AM, William Dorsett wrote: What brand recommendations do the group have for an battery charger to be plugged into a genset? Used to be Todd but at some point they lost favor. Thanks all. Bill Dorsett Sunwrights 1715 Leavenworth Manhattan, KS 785/539-1956 Home/Office ___ 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] Off-grid non-inverter battery charger recommendations?
How about an off grid inverter/charger that most off-griders would normally have ?? Almost any of the typical off grid I/C would do a much better job at charging. I would think that any el-cheap-o 12V inverter would balk at seeing much over 15V anyway. boB On 10/15/2012 11:27 AM, William Dorsett wrote: Thanks Aaron, but I need one that goes to 15.5 or 16V for equalizing the bank. Just got this back from Iota: Iota does not make any chargers that go to 15 volts output for equalizing. Thank you Iota Engineering Xantrex TruCharge 20 at least has an equalize setting, though I don't know how adjustable it is. Bill Dorsett Sunwrights Manhattan, KS *From:*re-wrenches-boun...@lists.re-wrenches.org [mailto:re-wrenches-boun...@lists.re-wrenches.org] *On Behalf Of *Aaron Mandelkorn *Sent:* Monday, October 15, 2012 10:24 AM *To:* RE-wrenches *Subject:* Re: [RE-wrenches] Off-grid non-inverter battery charger recommendations? Check out Iota. Aaron Mandelkorn NABCEP Certified PV Installer Renewable Energy Outfitters Box 65 Salida, CO. 81201 (970)596-3744 reoso...@gmail.com mailto:reoso...@gmail.com www.reosolar.com http://www.reosolar.com On Oct 15, 2012, at 9:14 AM, William Dorsett wrote: What brand recommendations do the group have for an battery charger to be plugged into a genset? Used to be Todd but at some point they lost favor. Thanks all. Bill Dorsett Sunwrights 1715 Leavenworth Manhattan, KS 785/539-1956 Home/Office ___ List sponsored by Home Power magazine List Address:RE-wrenches@lists.re-wrenches.org mailto: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 http://www.re-wrenches.org/etiquette.htm Check out participant bios: www.members.re-wrenches.org http://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] Off-grid non-inverter battery charger recommendations?
boB, The limit of 80-volts was to make an exception for single module devices like micro-inverters and for 48-volt battery systems and smaller. A change controller operating above 80V would be required to have an AFCI whether on or off grid if the array is mounted on a building. Bill. From: re-wrenches-boun...@lists.re-wrenches.org [mailto:re-wrenches-boun...@lists.re-wrenches.org] On Behalf Of boB Sent: Monday, October 15, 2012 11:50 AM To: RE-wrenches Subject: Re: [RE-wrenches] Off-grid non-inverter battery charger recommendations? How about an off grid inverter/charger that most off-griders would normally have ?? Almost any of the typical off grid I/C would do a much better job at charging. I would think that any el-cheap-o 12V inverter would balk at seeing much over 15V anyway. boB On 10/15/2012 11:27 AM, William Dorsett wrote: Thanks Aaron, but I need one that goes to 15.5 or 16V for equalizing the bank. Just got this back from Iota: Iota does not make any chargers that go to 15 volts output for equalizing. Thank you Iota Engineering Xantrex TruCharge 20 at least has an equalize setting, though I don't know how adjustable it is. Bill Dorsett Sunwrights Manhattan, KS From: re-wrenches-boun...@lists.re-wrenches.org [mailto:re-wrenches-boun...@lists.re-wrenches.org] On Behalf Of Aaron Mandelkorn Sent: Monday, October 15, 2012 10:24 AM To: RE-wrenches Subject: Re: [RE-wrenches] Off-grid non-inverter battery charger recommendations? Check out Iota. Aaron Mandelkorn NABCEP Certified PV Installer Renewable Energy Outfitters Box 65 Salida, CO. 81201 (970)596-3744 reoso...@gmail.com www.reosolar.com On Oct 15, 2012, at 9:14 AM, William Dorsett wrote: What brand recommendations do the group have for an battery charger to be plugged into a genset? Used to be Todd but at some point they lost favor. Thanks all. Bill Dorsett Sunwrights 1715 Leavenworth Manhattan, KS 785/539-1956 Home/Office ___ 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] Off-grid non-inverter battery charger recommendations?
Hi MIck, I often see your explanation for absorption charge phase. Consider this: While charging, current is applied without voltage regulation (CC). At the charge set point, PWM control (CV) takes place to regulate voltage. There is no control over current as the battery internal resistance dictates this. For example, if you have a pure DC source at a constant voltage attached to a battery, once the battery reaches that voltage, charge current will naturally start to decrease. I find it interesting that many people, including some manufacturers, believe a PV charge controller or AC battery charger is adjusting or tapering the current supplied to a battery when it is the other way around. Larry Crutcher Starlight Solar Power Systems (928) 342-9103 On Oct 15, 2012, at 10:27 AM, Mick Abraham wrote: Hi, Mechanix~ Bill Dorsett polled the group about recommended battery chargers for connection to a generator. Iota brand is the successor to Todd brand; I believe Iota bought the designs, tooling, etc. and these have appeal because of the relatively low cost per rated amp. They seem generator tolerant. The Todd design is a constant voltage type charger, however--basically an AC to DC converter with a fixed voltage output. In my experience, the 75 amp Todd type charger will deliver 75 amps only for a relatively short time when first connected to a low battery. As the battery's voltage comes up that presents a sort of back pressure which slows the rate of charge. That's not so bad if one has utility power always on to drive the charger, but if an engine generator is running... The inverter/chargers (with which we are all familiar) begin with a constant current part of the charge cycle--aka bulk charge. The charger is determined to sock the battery with the amperage we have requested in the setup; I think a pulse width modulation is going on where the charger hums up its voltage in order to keep the amps high even as the back pressure builds. When it's time for the absorption phase of the charge, the logic shifts to a constant voltage where the amps are gradually dialed lower in order to keep the battery at the target voltage so it can absorb. Ignoring the float phase which would come later, this overall charge regimen would be called CC/CV for constant current/constant voltage. The CV part of that is not much different from what a Todd style charger does; it's just that the Todd design does not precede that phase with a CC constant current phase. Some free-standing battery chargers have a CC/CV algorithm but those seem to cost as much or more than a comparably rated inverter/charger. Check the Magnum mod-square multi's, Bill, such as their RD series. As others on this List have noted, just the charge function is pretty good and since the inverter circuit is not pure sine, that keeps the cost lower. Built in time delay before it loads up the generator is an added benefit. Jolliness, Mick Abraham, Proprietor www.abrahamsolar.com Voice: 970-731-4675 ___ 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] Off-grid non-inverter battery charger recommendations?
Good answer, Mick. I've got an old Trace DR 1512 with charger, and these people have a very small inverter plugged into a wall outlet (old cigar plug wall outlets were max'd at 60watts). So they don't do much with it but might want some ability to run AC loads. I'd sell it to them cheap and they might be able to equalize the batteries. Need to check the max voltage output. As always great input, thanks for all your thoughts. Bill Dorsett Sunwrights Manhattan, KS From: re-wrenches-boun...@lists.re-wrenches.org [mailto:re-wrenches-boun...@lists.re-wrenches.org] On Behalf Of Mick Abraham Sent: Monday, October 15, 2012 12:27 PM To: RE-wrenches Subject: [RE-wrenches] Off-grid non-inverter battery charger recommendations? Hi, Mechanix~ Bill Dorsett polled the group about recommended battery chargers for connection to a generator. Iota brand is the successor to Todd brand; I believe Iota bought the designs, tooling, etc. and these have appeal because of the relatively low cost per rated amp. They seem generator tolerant. The Todd design is a constant voltage type charger, however--basically an AC to DC converter with a fixed voltage output. In my experience, the 75 amp Todd type charger will deliver 75 amps only for a relatively short time when first connected to a low battery. As the battery's voltage comes up that presents a sort of back pressure which slows the rate of charge. That's not so bad if one has utility power always on to drive the charger, but if an engine generator is running... The inverter/chargers (with which we are all familiar) begin with a constant current part of the charge cycle--aka bulk charge. The charger is determined to sock the battery with the amperage we have requested in the setup; I think a pulse width modulation is going on where the charger hums up its voltage in order to keep the amps high even as the back pressure builds. When it's time for the absorption phase of the charge, the logic shifts to a constant voltage where the amps are gradually dialed lower in order to keep the battery at the target voltage so it can absorb. Ignoring the float phase which would come later, this overall charge regimen would be called CC/CV for constant current/constant voltage. The CV part of that is not much different from what a Todd style charger does; it's just that the Todd design does not precede that phase with a CC constant current phase. Some free-standing battery chargers have a CC/CV algorithm but those seem to cost as much or more than a comparably rated inverter/charger. Check the Magnum mod-square multi's, Bill, such as their RD series. As others on this List have noted, just the charge function is pretty good and since the inverter circuit is not pure sine, that keeps the cost lower. Built in time delay before it loads up the generator is an added benefit. Jolliness, Mick Abraham, Proprietor www.abrahamsolar.com Voice: 970-731-4675 ___ 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
