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/
Boston Linux Meeting Wednesday, August 15, 2007 7PM Delivering the Power of Xen
When: August 15, 2007 7:00PM (6:30 for QA) Topic: XenSource and XenEnterprise: Delivering the Power of Xen Moderator: Rich Persaud, Systems Engineer, Xen Source Location: MIT Building E51 Room 315 A review of the Xen project and a demo of XenSource's XenEnterprise product. The presentation will briefly review XenSource, the Xen project, paravirtualization and the Xen hypervisor before introducing XenEnterprise and demonstrating the product and its features including an overview of VM lifecycle management, iSCSI SAN support, multi-processor support for scalable virtualization and other multi-threaded and compute-intensive applications, and easy-to-use management controls of CPU, disk and Network resources. XenSource will have CDs and will give away a Nintendo WII For much more information, and Parking please refer to http://www.blu.org/cgi-bin/calendar/2007-aug Additionally our after-meeting meeting will be at Characters in the Cambridge Marriott - a 2 minute walk from Building E51. Remember the next Installfest is on Saturday August 18th. I'll send out a separate notice. -- Jerry Feldman [EMAIL PROTECTED] Boston Linux and Unix user group http://www.blu.org PGP key id:C5061EA9 PGP Key fingerprint:053C 73EC 3AC1 5C44 3E14 9245 FB00 3ED5 C506 1EA9 signature.asc Description: PGP signature ___ 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/
