Re: [OT] Charging UPS batteries outside the UPS
On Wed, Aug 08, 2007 at 09:24:40PM -0400, Ben Scott wrote: On 8/8/07, mike ledoux [EMAIL PROTECTED] wrote: I've checked the voltage on the battery, and it's less than 2 volts DC. In that case, there is almost certainly at least one internal short in the battery, and no amount of charging is likely to fix it. It takes some serious work to get a 12V battery down to 2V. Even better: That was for each of the 24V packs. Your comment made me curious, so I pulled all the wiring off the individual units and measured each one. Each unit is giving between 0.5 and 0.7 volts DC. So either each unit has the same internal short, or they really are drained (or something else). There is almost no chance that you'll get those batteries to take a charge at all, if they were drained that low. As you're probably aware, each of those 12V batteries is made of 6 2V cells. Fully charged each of those 2V cells is good for about 2.15V, fully discharged is about 1.75V (for good, working cells). Generally speaking, if a 12V battery with no load is reading below ~10V, something is pretty badly wrong with the battery, usually a short across one or more of the cells. From what you're saying, you're reading less from the entire battery than a single discharged cell should provide, so I'm going to go out on a limb and guess that these batteries are pretty old, and heavily sulphated. You may be able to salvage the battery well enough to start the UPS by running an equalization cycle on it, but that is somewhat tricky/dangerous with a sealed battery as you're *trying* to overcharge in order to boil the electrolyte to break up the sulphation on the plates. Te battery was sitting, hooked-up, inside the UPS for I dunno how long. You can cold-start this UPS model (turn it on without AC input), so I expect it is always drawing at least a little power from the battery (since the UPS front panel is microprocessor controlled). Maybe that would do it? Yeah, PbA batteries do not store well when not kept fully charged. According to a doc on Panasonic website, these are, indeed, absorbed glass mat with calcium grids. Another doc does have dire warnings about charging, though. The short version is that without constant voltage control (whatever that means), the electrolyte breaks down and the battery performance is shot. Maybe they were overcharged and that's why their voltage is so low. It is perfectly safe to use any *quality* 12V PbA charger on an AGM battery. The only thing to worry about is that you don't try to charge too quickly, as that can generate excessive heat in the battery, causing the electrolyte to boil, which is a bit of a problem in a sealed battery. For batteries as small as typically used in a UPS I wouldn't charge at anything over 2A. -- [EMAIL PROTECTED] OpenPGP KeyID 0x57C3430B Holder of Past Knowledge CS, O- At first I thought, 'How could women be from Venus? It's got an atmosphere of poisonous gas!' And then I made the connection: potpourri! Larry Hollister ___ gnhlug-discuss mailing list gnhlug-discuss@mail.gnhlug.org http://mail.gnhlug.org/mailman/listinfo/gnhlug-discuss/
Re: [OT] Charging UPS batteries outside the UPS
Drew Van Zandt wrote: I would expect an automotive charger to exceed the 2.88A charge current by possibly quite a bit; it depends very much on the charger. (I suppose I'm saying you should RTFM for the charger, if you have one.) I know some chargers I've seen have 8A or even higher current ratings. I would expect the voltage of a car charger to be in the right ballpark, at least, but again that may be in the manual. Exceeding the 2.88A charge current by a large amount would be a Bad Thing (TM); battery damage or even explosions could result. Do not dispose of in fire, do not bend, fold, spindle or mutilate, no user servicable parts inside. Do not eat. Do not hit towards human or animal. Not a toy, keep out of reach of children. Not for use in medical or lifesaving equipment, may contain small parts. Contains energy equal to the mass multiplied by the speed of light squared. --DTVZ ___ I have not been following this thread closely, so somebody may have already made this suggestion. If so sorry. For you techies, E=IR, or more to the point, I=E/R. Since the automotive charger voltage is about 15 volts open circuit, and the battery voltage is unknown but near 0, an R=10 ohms will limit the charging current to 1.5 amps. In truth E=E(charger) - E(battery), so as the battery charges, I tapers off. This is an ideal situation, a tapered charge. Go to Radio Shack and buy a $1, 10 watt, 10 ohm resistor and hook up in series between the charger and the battery. Karl ___ gnhlug-discuss mailing list gnhlug-discuss@mail.gnhlug.org http://mail.gnhlug.org/mailman/listinfo/gnhlug-discuss/
Re: [OT] Charging UPS batteries outside the UPS
On Mon, Aug 06, 2007 at 10:10:30PM -0400, Ben Scott wrote: Off-topic but still techie question: Does anyone know anything about charging the batteries from a UPS using external equipment (i.e., not the charger built-in to the UPS)? Yes. I've got an APC Smart-UPS 3000 (P/N SU3000RM3U) which I picked up for free (someone was getting rid of it). It looks like it's in good condition, but it won't start[1]. I've checked the voltage on the battery, and it's less than 2 volts DC. An aggravating quirk with In that case, there is almost certainly at least one internal short in the battery, and no amount of charging is likely to fix it. It takes some serious work to get a 12V battery down to 2V. The battery consists of eight smaller units, wired together. The wiring is easily disconnected. Each unit is labeled 12 V, 7.2 Ah/20HR. Anyone if I can just hook each unit up to a regular automotive battery charger (one at a time) and charge them that way? As others of mentioned, that depends on the battery chemistry. Note well that sealed lead acid doesn't necessarily mean Gel. It could be an AGM battery, which will charge just fine with any decent PbA battery charger. OTOH, it sounds like the battery is already pretty well fscked, so even if it is a Gel battery you aren't likely to make things worse (using a standard charger on a Gel battery will not charge very well, and will certainly reduce the lifespan of the battery, but it isn't likely to explode unless something else is wrong). I have a few different chargers kicking around in my garage, I'd bet at least one of them supports the charge mode your battery needs, if you want to borrow one. -- [EMAIL PROTECTED] OpenPGP KeyID 0x57C3430B Holder of Past Knowledge CS, O- Software which OpenBSD uses and redistributes must be free to all (be they people or companies), for any purpose they wish to use it, including modification, use, peeing on, or even integration into baby mulching machines or atomic bombs to be dropped on Australia. Theo de Raadt ___ gnhlug-discuss mailing list gnhlug-discuss@mail.gnhlug.org http://mail.gnhlug.org/mailman/listinfo/gnhlug-discuss/
Re: [OT] Charging UPS batteries outside the UPS
On 8/7/07, Drew Van Zandt [EMAIL PROTECTED] wrote: OK, then I'll offer a real EE, knowledgeable about battery charging answer. Hey, now. Information based on formal education and grounded in scientific fact? This is the Internet, here. We can't have that. ;-) Tell me what the capacity is, and the model number, and I'll check the proper charging profile from the datasheet ... What, you're saying I should RTFM for the battery? :) Heh, I actually never thought of that. I typed the P/N from the side into Google, and sure enough, and found the datasheet as the second link. (Panasonic LC-R127R2P1, for those of you following along at home.) The datasheet gives Charge Method (Constant Voltage) for two scenarios: Cycle use (Repeating use) has an initial current of = 2.88 A, and a control voltage of 14.5 to 14.9 V. Trickle use has an initial current of = 1.08 A, and a control voltage of 13.6 to 13.8 V. I almost sort-of understand that. :) But I don't have the knowledge to translate it into What will happen if I hook it up to an automotive charger? Thanks! -- Ben ___ gnhlug-discuss mailing list gnhlug-discuss@mail.gnhlug.org http://mail.gnhlug.org/mailman/listinfo/gnhlug-discuss/
Re: [OT] Charging UPS batteries outside the UPS
On 8/8/07, mike ledoux [EMAIL PROTECTED] wrote: I've checked the voltage on the battery, and it's less than 2 volts DC. In that case, there is almost certainly at least one internal short in the battery, and no amount of charging is likely to fix it. It takes some serious work to get a 12V battery down to 2V. Even better: That was for each of the 24V packs. Your comment made me curious, so I pulled all the wiring off the individual units and measured each one. Each unit is giving between 0.5 and 0.7 volts DC. So either each unit has the same internal short, or they really are drained (or something else). Te battery was sitting, hooked-up, inside the UPS for I dunno how long. You can cold-start this UPS model (turn it on without AC input), so I expect it is always drawing at least a little power from the battery (since the UPS front panel is microprocessor controlled). Maybe that would do it? Note well that sealed lead acid doesn't necessarily mean Gel. A. Good to know. It could be an AGM battery, which will charge just fine with any decent PbA battery charger. According to a doc on Panasonic website, these are, indeed, absorbed glass mat with calcium grids. Another doc does have dire warnings about charging, though. The short version is that without constant voltage control (whatever that means), the electrolyte breaks down and the battery performance is shot. Maybe they were overcharged and that's why their voltage is so low. http://www.panasonic.com/industrial/battery/oem/chem/seal/index.html -- Ben ___ gnhlug-discuss mailing list gnhlug-discuss@mail.gnhlug.org http://mail.gnhlug.org/mailman/listinfo/gnhlug-discuss/
Re: [OT] Charging UPS batteries outside the UPS
The datasheet gives Charge Method (Constant Voltage) for two scenarios: Cycle use (Repeating use) has an initial current of = 2.88 A, and a control voltage of 14.5 to 14.9 V. Trickle use has an initial current of = 1.08 A, and a control voltage of 13.6 to 13.8 V. I almost sort-of understand that. :) But I don't have the knowledge to translate it into What will happen if I hook it up to an automotive charger? I would expect an automotive charger to exceed the 2.88A charge current by possibly quite a bit; it depends very much on the charger. (I suppose I'm saying you should RTFM for the charger, if you have one.) I know some chargers I've seen have 8A or even higher current ratings. I would expect the voltage of a car charger to be in the right ballpark, at least, but again that may be in the manual. Exceeding the 2.88A charge current by a large amount would be a Bad Thing (TM); battery damage or even explosions could result. Do not dispose of in fire, do not bend, fold, spindle or mutilate, no user servicable parts inside. Do not eat. Do not hit towards human or animal. Not a toy, keep out of reach of children. Not for use in medical or lifesaving equipment, may contain small parts. Contains energy equal to the mass multiplied by the speed of light squared. --DTVZ ___ gnhlug-discuss mailing list gnhlug-discuss@mail.gnhlug.org http://mail.gnhlug.org/mailman/listinfo/gnhlug-discuss/
Re: [OT] Charging UPS batteries outside the UPS
On Monday 06 August 2007 22:10, Ben Scott wrote: Hi all, Off-topic but still techie question: Does anyone know anything about charging the batteries from a UPS using external equipment (i.e., not the charger built-in to the UPS)? The battery consists of eight smaller units, wired together. The wiring is easily disconnected. Each unit is labeled 12 V, 7.2 Ah/20HR. Anyone if I can just hook each unit up to a regular automotive battery charger (one at a time) and charge them that way? It is safe to recharge them with a conventional automotive battery charger as you suggest. Recharge them at a low rate. If anything goes wrong, they will just get hot or not take a charge. At a low charge rate, the battery cannot get hot enough to burn up or damage its surrounding. My auxiliary charger has a 6 amp and 2 amp setting. (You are welcome to use it - I will email it to you.) 2 amps at 13V is only 26W, which is not going to raise the temperature of a large surface area by much. V DC is. [4] Severe discharge typically also means the battery will not hold a load to spec, so it's an indication the battery is no good; no point in a UPS without a battery; loose battery connector indication; Actually, when lead-acid batteries lose capacity after many partial discharges, the recommendation is to have a deep discharge and complete recharge. That brings back some of the capacity. what if the customer is stupid and didn't connect the battery. Most batteries, particularly lead-acid batteries, self discharge whether connected or not. Keeping them in the refrigerator helps - if you can get the cooperation of the rest of the household. Jim Kuzdrall ___ gnhlug-discuss mailing list gnhlug-discuss@mail.gnhlug.org http://mail.gnhlug.org/mailman/listinfo/gnhlug-discuss/
Re: [OT] Charging UPS batteries outside the UPS
Ben Scott writes: Now, I don't want to have to spend $350 on a replacement battery only to find out that it's the UPS itself that's shot. I'm thinking if I can find some way to charge up the battery to minimum levels, I can at least test the UPS to see if it works. It doesn't have to hold a load. $350 is a bit high.. I've bought replacement batteries from here many times without issues: http://www.powersupersite.com/MZIproducts.cfm?full=1ID=RBK12-f 175.00 + ~25 shipping for the RBC12 The battery consists of eight smaller units, wired together. The wiring is easily disconnected. Each unit is labeled 12 V, 7.2 Ah/20HR. Anyone if I can just hook each unit up to a regular automotive battery charger (one at a time) and charge them that way? I'd say probably so, but dont blame me if they explode. useful info here: http://en.wikipedia.org/wiki/Lead-acid_battery -- Dave ___ gnhlug-discuss mailing list gnhlug-discuss@mail.gnhlug.org http://mail.gnhlug.org/mailman/listinfo/gnhlug-discuss/
Re: [OT] Charging UPS batteries outside the UPS
[EMAIL PROTECTED] writes: First, confirm that these batteries are wired IN PARALLEL, NOT IN SERIES. (If they are in series, you're looking at a highly non-standard 96V implementation. No problem, though... just disconnect them all and charge them separately.) This ups takes 2 sets of 2-parallel 2-series providing 2 24V plugs with 4 batteries each. -- Dave ___ gnhlug-discuss mailing list gnhlug-discuss@mail.gnhlug.org http://mail.gnhlug.org/mailman/listinfo/gnhlug-discuss/
Re: [OT] Charging UPS batteries outside the UPS
On Monday 06 August 2007 22:10, Ben Scott wrote: Now, I don't want to have to spend $350 on a replacement battery only to find out that it's the UPS itself that's shot. For what it's worth, APC.com lists their replacement batteries for $280 for an SU3000RM3U. I've had bad luck with non-APC sources for replacement batteries, but your mileage may vary. Hopefully, you can get away with recharging the system as you're getting suggestions to do though... -N ___ gnhlug-discuss mailing list gnhlug-discuss@mail.gnhlug.org http://mail.gnhlug.org/mailman/listinfo/gnhlug-discuss/
Re: [OT] Charging UPS batteries outside the UPS
[EMAIL PROTECTED] wrote: IIRC, APC UPSs (how's that for an acronym?) generally ship with the batteries DISCONNECTED. When you get it and first open the box, the instructions tell you how to hook them up. U.S. FAA DOT requests that batteries are disconnected. during shipment. It is a voluntary program, as far as I know, but all the UPSes I've seen in the last few years, no matter who made them, come disconnected. So, it isn't just APC. In one brand, they had a locking slide switch which made the connection rather than having to open the unit to connect the battery wire, like APC does. -- Dan Jenkins ([EMAIL PROTECTED]) Rastech Inc., Bedford, NH, USA --- 1-603-206-9951 *** Technical Support Excellence for over a Quarter Century ___ gnhlug-discuss mailing list gnhlug-discuss@mail.gnhlug.org http://mail.gnhlug.org/mailman/listinfo/gnhlug-discuss/
Re: [OT] Charging UPS batteries outside the UPS
Top Reply, bad netiquette etc, but I have a few of those sealed lead acid batteries, almost new and unused, $10 each if you want to collect them from Manchester. Chris On 8/7/07, Dan Jenkins [EMAIL PROTECTED] wrote: [EMAIL PROTECTED] wrote: IIRC, APC UPSs (how's that for an acronym?) generally ship with the batteries DISCONNECTED. When you get it and first open the box, the instructions tell you how to hook them up. U.S. FAA DOT requests that batteries are disconnected. during shipment. It is a voluntary program, as far as I know, but all the UPSes I've seen in the last few years, no matter who made them, come disconnected. So, it isn't just APC. In one brand, they had a locking slide switch which made the connection rather than having to open the unit to connect the battery wire, like APC does. -- Dan Jenkins ([EMAIL PROTECTED]) Rastech Inc., Bedford, NH, USA --- 1-603-206-9951 *** Technical Support Excellence for over a Quarter Century ___ gnhlug-discuss mailing list gnhlug-discuss@mail.gnhlug.org http://mail.gnhlug.org/mailman/listinfo/gnhlug-discuss/ -- IBA #15631 ___ gnhlug-discuss mailing list gnhlug-discuss@mail.gnhlug.org http://mail.gnhlug.org/mailman/listinfo/gnhlug-discuss/
Re: [OT] Charging UPS batteries outside the UPS
This is an amalgamated reply. Thanks for all the responses, everyone, it's been informative and educational, as always. :) On 8/7/07, [EMAIL PROTECTED] [EMAIL PROTECTED] wrote: Most UPSs use gel cell batteries ... These are gel cells. So-called sealed lead-acid. On 8/7/07, Jim Kuzdrall [EMAIL PROTECTED] wrote: My auxiliary charger ... (You are welcome to use it - I will email it to you.) Rather than emailing the charger, just hook it up to your computer, and use an SSH tunnel to transmit the charging current to me. ;-) On 8/7/07, Jim Kuzdrall [EMAIL PROTECTED] wrote: It is safe to recharge them with a conventional automotive battery charger as you suggest. ... If anything goes wrong, they will just get hot or not take a charge. On 8/7/07, [EMAIL PROTECTED] [EMAIL PROTECTED] wrote: Gel cells require a different current/time charging profile than other types of batteries. ... a standard 12V battery charger ... CAN DESTROY THE BATTERIES! H. So much for an easy answer. :-) http://en.wikipedia.org/wiki/Gel_battery doesn't really give much of a clue, other than to say Charging with a constant voltage ... can cause a rapid initial current, which doesn't really help me much. Does that just mean it doesn't work as well, or that it is don't-cross-the-streams-bad? Still, maybe I can find a charger that has a gel switch on it somewhere... On the third hand, the batteries are useless anyway, so maybe I'll just hook 'em up to what I've got available and see what happens. Outside, away from anything combustible, and in a pan. :) On 8/7/07, [EMAIL PROTECTED] [EMAIL PROTECTED] wrote: First, confirm that these batteries are wired IN PARALLEL, NOT IN SERIES. The battery in this unit consists of two packs of four units each. In each pack, two pairs of units are wired in series, and the pairs are then wired in parallel (within the pack). The wiring in the UPS connects the packs in series. So, the units are 12 V, the packs 24 V, and the whole battery is 48 V. Keep in mind this is a 2250 watt, 3000 VA UPS. The battery is bigger than what you would find in something at Circuit City... :) With regard to replacement batteries: I'm aware of pricing and OEM vs third-party and so on. The $350 was a rough number, partly hyperbole, and also reflected S/H (they are rather heavy). Even if I can find a replacement for $CHEAPER, that's still more than I want to spend on a potentially dead UPS. :-) On 8/7/07, Jim Kuzdrall [EMAIL PROTECTED] wrote: [4] Severe discharge typically also means the battery will not hold a load to spec ... Actually, when lead-acid batteries lose capacity after many partial discharges, the recommendation is to have a deep discharge and complete recharge. Like I said, I find APC's explanation rather suspect. Aside from technical concerns, they have a Conflict Of Interest (selling me new batteries). On 8/7/07, [EMAIL PROTECTED] [EMAIL PROTECTED] wrote: FWIW, the APC UPSs come with some kind of supposedly super sophisticated warranty. I suspect you're thinking of the equipment protection stuff, where APC will pay to replace any equipment the UPS failed to protect from damage due to a power transient. The warranty on the UPSes themselves are fairly standard (some number of years). They do pay shipping both ways. Dead batteries are not covered, though. And I believe this unit is out-of-warranty. Either way, if I call support, they'll just tell me to replace the batteries first (not an unreasonable stance, given the situation). -- Ben ___ gnhlug-discuss mailing list gnhlug-discuss@mail.gnhlug.org http://mail.gnhlug.org/mailman/listinfo/gnhlug-discuss/
Re: [OT] Charging UPS batteries outside the UPS
On 8/7/07, Jim Kuzdrall [EMAIL PROTECTED] wrote: It is safe to recharge them with a conventional automotive battery charger as you suggest. ... If anything goes wrong, they will just get hot or not take a charge. On 8/7/07, [EMAIL PROTECTED] [EMAIL PROTECTED] wrote: Gel cells require a different current/time charging profile than other types of batteries. ... a standard 12V battery charger ... CAN DESTROY THE BATTERIES! H. So much for an easy answer. :-) OK, then I'll offer a real EE, knowledgeable about battery charging answer. Tell me what the capacity is, and the model number, and I'll check the proper charging profile from the datasheet or give you a SWAG on proper procedure. (Had to build a charger for both SLA and Ni-Cad at my undergrad, and have looked at NiMH recently for battery backed apps at work.) Here's some general info: Depending on cell type, there's a maximum charging rate that doesn't damage the electrodes or do weird things to the electrolyte. This rate is generally something like C/10 or C/20, where C is the battery capacity. Again, depending on the battery type the divisor changes. A pretty good job of charging (which would suffice for you) can be done just by current-limiting the charging supply to stay under this number, and then charging for roughly the right amount of time (one of those light timers will do in a pinch for limiting the time.) Once the battery's been charged at the high rate for the right amount of time, most systems switch to either a trickle charge or occasional cycles of trickle charge. SLA batteries are some of the toughest batteries out there as far as charge/discharge rates. Fancy charging systems will even have 3 or 4 charging modes they cycle through on a charge, and then a different cycle for maintaining charge once the batteries are full. Now, as to the proper amount of time... you'd think that if you're charging at C/10, that 10 hours would be right, but they're not 100% efficient at returning stored energy; it will typically take around 30-50% longer than the above calculation suggests. Varies wildly with battery type. That's all fairly vague; with a battery datasheet or possibly a model # I might be able to give you excruciatingly proper procedure. --DTVZ ___ gnhlug-discuss mailing list gnhlug-discuss@mail.gnhlug.org http://mail.gnhlug.org/mailman/listinfo/gnhlug-discuss/
Subject: [OT] Charging UPS batteries outside the UPS
Ben - I've almost never seen an APC Smart-UPS that was actually defective. I'd certainly take a chance on the batteries. There's an outfit on Ebay that sells a privately branded ZEUS SLA battery at a very reasonable price (batteryman20). I've ordered many times had very good luck with their batteries. They have a RBC12 set of batteries for $66.75 with $31.88 shipping. If your batteries are down to 2v they will never take enough of a charge to make the UPS trigger on (in my experience). Also one of the links in most APC supplies is a fuse. I'm not sure about the 3000 - but it's true of the 1000 and 1500va units. Make sure that it isn't open. Good luck! - Gary From: Ben Scott [EMAIL PROTECTED] To: Greater NH Linux User Group gnhlug-discuss@mail.gnhlug.org Date: Mon, 6 Aug 2007 22:10:30 -0400 Subject: [OT] Charging UPS batteries outside the UPS I've got an APC Smart-UPS 3000 (P/N SU3000RM3U) which I picked up for free (someone was getting rid of it). ___ gnhlug-discuss mailing list gnhlug-discuss@mail.gnhlug.org http://mail.gnhlug.org/mailman/listinfo/gnhlug-discuss/
Re: [OT] Charging UPS batteries outside the UPS
I ran scared from EE classes. My neighbor has a 1500VA APC UPS of similar vintage, perhaps from a similar scrapheap, marked as 'dead'. He 'jumpstarted' it with an automotive battery charger/conditioner, and it works fine a couple years later. If I were to guess, perhaps his unit only had one of the 4 cells you had, for 12V, so you might need to charge each of your 4 12V parts separately then reassemble them. A colleague and I once bought an APC unit very similar to yours off eBay, labeled 'works, no batteries'. We found the batteries were made by panasonic and after a bit of tracking found them to be motorcycle batteries. We ordered a complete set for ~$120 from an auto supply and wired them back up like the originals. As far as I know, that UPS is still running a small bank of storage servers and hasn't caused any fires. Total cost was ~$220, which was quite a deal at the time. -Bill - Bill McGonigle, Owner Work: 603.448.4440 BFC Computing, LLC Home: 603.448.1668 [EMAIL PROTECTED] Cell: 603.252.2606 http://www.bfccomputing.com/Page: 603.442.1833 Blog: http://blog.bfccomputing.com/ VCard: http://bfccomputing.com/vcard/bill.vcf ___ gnhlug-discuss mailing list gnhlug-discuss@mail.gnhlug.org http://mail.gnhlug.org/mailman/listinfo/gnhlug-discuss/
[OT] Charging UPS batteries outside the UPS
Hi all, Off-topic but still techie question: Does anyone know anything about charging the batteries from a UPS using external equipment (i.e., not the charger built-in to the UPS)? I've got an APC Smart-UPS 3000 (P/N SU3000RM3U) which I picked up for free (someone was getting rid of it). It looks like it's in good condition, but it won't start[1]. I've checked the voltage on the battery, and it's less than 2 volts DC. An aggravating quirk with most APC UPSes is that they won't start[2] if the battery is disconnected or dead[3]. Now, I don't want to have to spend $350 on a replacement battery only to find out that it's the UPS itself that's shot. I'm thinking if I can find some way to charge up the battery to minimum levels, I can at least test the UPS to see if it works. It doesn't have to hold a load. The battery consists of eight smaller units, wired together. The wiring is easily disconnected. Each unit is labeled 12 V, 7.2 Ah/20HR. Anyone if I can just hook each unit up to a regular automotive battery charger (one at a time) and charge them that way? [1] No lights, no beeps, no clicks, no fans, no output, minuscule power draw (0.04 A AC). [2] This is supposedly by design. They give reasons[4], although I'm not sure I believe them. Supposedly, the latest APC models can start without a battery, but that doesn't help me. [3] Dead being defined as less than some acceptable voltage, which 2 V DC is. [4] Severe discharge typically also means the battery will not hold a load to spec, so it's an indication the battery is no good; no point in a UPS without a battery; loose battery connector indication; what if the customer is stupid and didn't connect the battery. -- Ben ___ gnhlug-discuss mailing list gnhlug-discuss@mail.gnhlug.org http://mail.gnhlug.org/mailman/listinfo/gnhlug-discuss/
