Hi Folks,
Can anyone recommend a good place to look for a UPS within reasonable reach of Ely?
I've been running a Belkin 625VA "Regulator Pro Gold" very happily for some 4 years, but unfortunately its battery is now going dodgy.
In view of Belkin's approach to battery replacement, I now want to simply replace the whole UPS.
So I'm looking for 600+ watts, at least 3 battery-protected 220C power outlets.
One good thing about the Belkin was that its controlling software came also in a Linux version, allowing clean shutdown of connected machines.
I've had a look in PC World in Cambridge, and their current stock of stuff is not up to what I'm after, though maybe I could go for a lower-rated UPS per machine. Not keen on proliferations, though!
Ely itself is useless for this sort of thing. I've not tried Downham Market (prior expectations low anyway), and the one time I did browse round PC World at King's Lynn I wasn't that impressed. But people must manage somehow round here!
As to Belkin's support: You have to contact them by phone. Took several calls over days, on occasion hanging on for up to 20 min, to speak to someone. Only to be told that they're not licensed to sell the batteries separately in Europe, so I'd have to send the unit back to them and they'd return it with a replacement battery. "It should be done within a week."
No thanks. Apart from the hassle and expense of boxing it up and sending it myself, in these parts you don't want to be UPS-less that long! (And it might be longer).
Ah well ...
Thanks for any suggestions! Ted.
-------------------------------------------------------------------- E-Mail: (Ted Harding) Ted.Harding@nessie.mcc.ac.uk Fax-to-email: +44 (0)870 094 0861 Date: 16-Nov-05 Time: 15:08:33 ------------------------------ XFMail ------------------------------
On 11/16/05, Ted Harding Ted.Harding@nessie.mcc.ac.uk wrote:
Can anyone recommend a good place to look for a UPS within reasonable reach of Ely?
So I'm looking for 600+ watts, at least 3 battery-protected 220C power outlets.
One good thing about the Belkin was that its controlling software came also in a Linux version, allowing clean shutdown of connected machines.
I've had a look in PC World in Cambridge, and their current stock of stuff is not up to what I'm after, though maybe I could go for a lower-rated UPS per machine. Not keen on proliferations, though!
Since you made it as far as PC World, how about an APC unit, possibly from WOC? All the Linux support you need is already in most distributions (certainly no trouble with Debian Sarge and USB :-)
APC batteries look easy to replace, but I couldn't comment on their availability.
Tim.
APC batteries look easy to replace, but I couldn't comment on their availability.
I recently replaced the batteries in my APC UPS and bought them from Riello in Wrexham (http://www.riello-ups.co.uk)
The APC parts would have cost £78 + VAT, but Riello supplied them for £30 including VAT and postage.
Stuart.
Tim Green wrote:
APC batteries look easy to replace, but I couldn't comment on their availability.
MDS Batteries has a range.
I've been using two APC SmartUPS 700 (SU700INET), with a serial cable. Gentoo, and FreeBSD before it could see it fine.
I initially had a problem running them against diesel generator power, but it turns out there is a switch at the back to make it less picky about its input supply.
-- Martijn
On Wednesday 16 November 2005 15:26, Tim Green wrote:
On 11/16/05, Ted Harding Ted.Harding@nessie.mcc.ac.uk wrote:
Can anyone recommend a good place to look for a UPS within reasonable reach of Ely?
APC batteries look easy to replace, but I couldn't comment on their availability.
I was fortunate to aquire a number of APC 500VA units a while back. A couple had dodgy batteries, but they are a "standard" sealed lead acid battery. Norwich is fortunate to have a specialist battery supplier, and the required units were in stock for some £20 each.
If your Belkin UPS is still serviceable, I would certainly recommend seeking out a replacent battery - It shouldn't be too expensive, and would be cheaper than purchasing a replacement UPS.
Regards, Paul.
APC batteries look easy to replace, but I couldn't comment on their availability.
I was fortunate to aquire a number of APC 500VA units a while back. A couple had dodgy batteries, but they are a "standard" sealed lead acid battery. Norwich is fortunate to have a specialist battery supplier, and the required units were in stock for some £20 each.
If your Belkin UPS is still serviceable, I would certainly recommend seeking out a replacent battery - It shouldn't be too expensive, and would be cheaper than purchasing a replacement UPS.
Regards, Paul.
Most the batteries require regular re-conditioning which usually involves a light or a fan, a trickle charger and a lot of spare time.
JT
On Wed, Nov 16, 2005 at 03:52:01PM +0000, James Taylor wrote:
Most the batteries require regular re-conditioning which usually involves a light or a fan, a trickle charger and a lot of spare time.
I was under the impression that UPS use lead acid batteries as they don't require conditioning and discharging them fully is not a good idea at all as it will wreck the battery.
Thanks Adam
On Wed, Nov 16, 2005 at 03:52:01PM +0000, James Taylor wrote:
Most the batteries require regular re-conditioning which usually involves a light or a fan, a trickle charger and a lot of spare time.
I was under the impression that UPS use lead acid batteries as they don't require conditioning and discharging them fully is not a good idea at all as it will wreck the battery.
It depends on the particular battery. Some are specially designed for deep discharge cycles.
Peter
On Wed, Nov 16, 2005 at 04:31:46PM -0000, Peter Onion wrote:
On Wed, Nov 16, 2005 at 03:52:01PM +0000, James Taylor wrote:
Most the batteries require regular re-conditioning which usually involves a light or a fan, a trickle charger and a lot of spare time.
I was under the impression that UPS use lead acid batteries as they don't require conditioning and discharging them fully is not a good idea at all as it will wreck the battery.
It depends on the particular battery. Some are specially designed for deep discharge cycles.
Aye, but you wouldn't put them into a UPS would you? The bigger UPS that I have worked with all used very large truck/lorry batteries, which as I understand it are designed to produce a large amount of power for a short time (i.e. to get the engine started) so using them in a UPS was for the same reasons (i.e. you want lots of power for a very short amount of time so you could either turn all your computers off or have your diesel generator kick in).
Thanks Adam
Aye, but you wouldn't put them into a UPS would you? The bigger UPS that I have worked with all used very large truck/lorry batteries, which as I understand it are designed to produce a large amount of power for a short time (i.e. to get the engine started) so using them in a UPS was for the same reasons (i.e. you want lots of power for a very short amount of time so you could either turn all your computers off or have your diesel generator kick in).
But if you don't have a generator as well then you possibly would want the UPS batteries to last as long as possible and then a deep cycle battery would be called for I would think ? Note I'm not a UPS expert !
Peter
On Wed, Nov 16, 2005 at 04:51:19PM -0000, Peter Onion wrote:
But if you don't have a generator as well then you possibly would want the UPS batteries to last as long as possible and then a deep cycle battery would be called for I would think ? Note I'm not a UPS expert !
Nope, because having enough batteries and a large enough UPS to run a data center for a long time would cost many more times the cost of a generator ;)
Thanks Adam
On Wed, Nov 16, 2005 at 07:07:39PM +0000, Peter Onion wrote:
On Wed, 2005-11-16 at 17:55 +0000, Adam Bower wrote:
Nope, because having enough batteries and a large enough UPS to run a data center for a long time would cost many more times the cost of a generator ;)
Yes, because I wasn't talking about Data Centre scale UPSs.
Well for a "home scale" UPS you are looking at perhaps something around 1Kva which will give you up to 10 minutes runtime then you would be looking at paying 100-150 quid.
Whereas you can buy a 2.3Kva Generator for 200-250 quid.
Adam
On Wed, 2005-11-16 at 19:13 +0000, Adam Bower wrote:
On Wed, Nov 16, 2005 at 07:07:39PM +0000, Peter Onion wrote:
On Wed, 2005-11-16 at 17:55 +0000, Adam Bower wrote:
Nope, because having enough batteries and a large enough UPS to run a data center for a long time would cost many more times the cost of a generator ;)
Yes, because I wasn't talking about Data Centre scale UPSs.
Well for a "home scale" UPS you are looking at perhaps something around 1Kva which will give you up to 10 minutes runtime then you would be looking at paying 100-150 quid.
1kVa for 10 min ? Some tiddly little battery in it then ?
I've got a couple of 100Ah 12V batteries sitting here for running ex-military 24V radios so that's 1kW for well over an hour !
Peter
Whereas you can buy a 2.3Kva Generator for 200-250 quid.
Adam
On Wednesday 16 November 2005 19:37, Peter Onion wrote:
Well for a "home scale" UPS you are looking at perhaps something around 1Kva which will give you up to 10 minutes runtime then you would be looking at paying 100-150 quid.
1kVa for 10 min ? Some tiddly little battery in it then ?
The VA rating on a UPS is a measure of the power output. Unfortunately this does not correlate to the AH rating of the internal battery. A ten minute life would equate to a 12-15AH battery. If you wanted a longer up time, it is possible to source a UPS with a bigger battery, but it would be more expensive.
Regards, Paul.
On 16-Nov-05 Tim Green wrote:
On 11/16/05, Ted Harding Ted.Harding@nessie.mcc.ac.uk wrote:
Can anyone recommend a good place to look for a UPS within reasonable reach of Ely?
So I'm looking for 600+ watts, at least 3 battery-protected 220C power outlets.
One good thing about the Belkin was that its controlling software came also in a Linux version, allowing clean shutdown of connected machines.
I've had a look in PC World in Cambridge, and their current stock of stuff is not up to what I'm after, though maybe I could go for a lower-rated UPS per machine. Not keen on proliferations, though!
Since you made it as far as PC World, how about an APC unit, possibly from WOC? All the Linux support you need is already in most distributions (certainly no trouble with Debian Sarge and USB :-)
APC batteries look easy to replace, but I couldn't comment on their availability.
I've had a look at WOC's wevsite (I assume you mean World of Computers om Milton Road). It does look as though they might have something available in the right range.
Interesting subsequent discussion ...
One question: When I look through especially APC stuff on the Web, I note that they give different numbers for VA and for Watts, e.g.
APC Smart-UPS SC, 620VA/390W, Input 230V/Output 230V, Interface Port DB-9 RS-232
I've always been under the impression (ever since I learned electricity when I was little) that Watts = Volts*Amps, so VA should equal Watts, No? Or have I been living a lie? Or does VA mean something different in this context?
Another question: One thing I could try is simply taking the dying battery out of the Belkin unit, and jump-leading a car battery to the internal battery cables, at any rate as a stop-gap until I can get something else sorted out.
However, as people have been discussing, there's an issue about the power demand when it goes into battery mode. I got the Belkin at 625VA (?Watts) to be on the safe side, but I reckon it would need to stand 400, since I have 2 machines on it along with a few sundries (modem, TFT monitor, cordles phone, and the like).
So, I wonder what a normal car battery (of which I have one spare) can support as peak current?
Since the spec of the Belkin battery is 12V (but no info about current rating) the voltage would be OK.
I also have a small motorcycle battery (12V) which I bought so that I could run a laptop which has a totally shot battery (this machine runs happily on 12V) when not near mains, and the battery keep the laptop going for about 5 hours; but I'd be doubtful about drawing even 240W (20A) from that battery.
But I just don't know what these sorts of basic lead/acid battery can stand. Any knowledgeable folk out there?
I'm not into using the UPS for long-term backup. The real need is
a) To kick in and stabilise the output voltage when the mains voltage droops (fairly frequent)
b) To supply power during brief outages (a few seconds, and pretty frequent, often accompanied by spikes)
c) To supply power for at least 5 minutes when the mains goes down altogether, allowing the machines time to shutdown cleanly under cntrol from the UPS (happens often enough not to be ignorable -- e.g. trees on the O/H cables in storms, farmer ploughs up the U/G cable, "snow on the line", all of which have happened).
So maybe the vehicle battery solution might be OK. Or not?
Thanks, Ted.
-------------------------------------------------------------------- E-Mail: (Ted Harding) Ted.Harding@nessie.mcc.ac.uk Fax-to-email: +44 (0)870 094 0861 Date: 16-Nov-05 Time: 18:08:03 ------------------------------ XFMail ------------------------------
On Wed, Nov 16, 2005 at 06:08:05PM -0000, Ted Harding wrote:
So, I wonder what a normal car battery (of which I have one spare) can support as peak current?
It should be on the label for the battery.
So maybe the vehicle battery solution might be OK. Or not?
I have seen a guide on the internet that is how to build your own UPS using common or garden electrical supplies and batteries (google will know about it). Of course this will involve electrical know-how and will not have a simple way of telling your computer to "shut-down now, batteries nearly flat!". Oh, and I'm guessing that there may be some caveats about hydrogen production (big badda B00M!!). Personally, I'd not want to attempt it as I don't have the know-how but YMMV.
Thanks Adam
(Ted Harding) wrote:
I've always been under the impression (ever since I learned electricity when I was little) that Watts = Volts*Amps, so VA should equal Watts, No? Or have I been living a lie? Or does VA mean something different in this context?
With AC it's more complex. See:
ftp://www.apcmedia.com/salestools/SADE-5TNQYD_R0_EN.pdf ftp://www.apcmedia.com/salestools/SADE-5TNQYF_R0_EN.pdf ftp://www.apcmedia.com/salestools/SADE-5TNQYL_R0_EN.pdf
-- Martijn
On Wednesday 16 November 2005 18:08, Ted Harding wrote:
But I just don't know what these sorts of basic lead/acid battery can stand. Any knowledgeable folk out there?
A quick look at the battery in a 500VA APC UPS - 12v 7AH. At full load, this gives me a 2 minutes, or 14 minutes at half load. A typical car (or motorcycle) battery would extend these times considerably.. Car batteries can deliver in excess of 350A for very short periods.
I'm not into using the UPS for long-term backup. The real need is
a) To kick in and stabilise the output voltage when the mains voltage droops (fairly frequent)
b) To supply power during brief outages (a few seconds, and pretty frequent, often accompanied by spikes)
c) To supply power for at least 5 minutes when the mains goes down altogether, allowing the machines time to shutdown cleanly under cntrol from the UPS (happens often enough not to be ignorable -- e.g. trees on the O/H cables in storms, farmer ploughs up the U/G cable, "snow on the line", all of which have happened).
So maybe the vehicle battery solution might be OK. Or not?
http://www.apcc.com/products/category.cfm?id=13 shows several options. To select the best UPS for a five minute period would require you to aduit the total power consumption of the hardware.. For a 400W load with a five minute "up time", you'd probably need to look at something in the 750-800VA range.
As a side note, a friend in the back waters of Georgia runs his UPS of a car battery, and has done so for a number of years. Brown outs and power cuts are an almost weekly event down there !
Regards, Paul.
The message 200511161930.35244.bdi-emc@ntlworld.com from Paul bdi-emc@ntlworld.com contains these words:
A quick look at the battery in a 500VA APC UPS - 12v 7AH. At full load, this gives me a 2 minutes, or 14 minutes at half load. A typical car (or motorcycle) battery would extend these times considerably.. Car batteries can deliver in excess of 350A for very short periods.
But you'd have to be sure the charging circuit can without burning out deliver the current the larger accumulator will draw.
On Wed, Nov 16, 2005 at 11:58:34PM +0000, Anthony Anson wrote:
The message 200511161930.35244.bdi-emc@ntlworld.com from Paul bdi-emc@ntlworld.com contains these words:
A quick look at the battery in a 500VA APC UPS - 12v 7AH. At full load, this gives me a 2 minutes, or 14 minutes at half load. A typical car (or motorcycle) battery would extend these times considerably.. Car batteries can deliver in excess of 350A for very short periods.
But you'd have to be sure the charging circuit can without burning out deliver the current the larger accumulator will draw.
A bigger battery won't take more charging current, it'll just take longer to charge. The internal resistance of just about *any* lead acid battery will be negligable compared with that of the charging circuitry, the charging circuitry will set the current at any given voltage and will not be affected by the (negligable) internal resistance of the battery.
Does anyone have any experience with PCI-E graphics cards ?
I've purchased a ATI X800-GTO to put in my new AMD 64 box, but I'm confused by what it says on the box ... "Mother board must support specialized 12V connector for graphics cards" (Or words to that effect).
Now there is space on the graphics card for a 6 pin (2x3) socket but there is not one mounted there, so I'm guessing that I don't need to provide this particular version of the card with any additional power (other than what it can draw from the PCI-E connector).
Any thoughts ?
Peter
On Thu, 2005-11-17 at 10:00 +0000, Peter Onion wrote:
Does anyone have any experience with PCI-E graphics cards ?
I've purchased a ATI X800-GTO to put in my new AMD 64 box, but I'm confused by what it says on the box ... "Mother board must support specialized 12V connector for graphics cards" (Or words to that effect).
Now there is space on the graphics card for a 6 pin (2x3) socket but there is not one mounted there, so I'm guessing that I don't need to provide this particular version of the card with any additional power (other than what it can draw from the PCI-E connector).
Any thoughts ?
Peter
Hi Peter,
On both of my PCI Express equipped machines, there is a Harddrive style power connector right next to the PCIE slot which needs a power cable plugged in. This is in addition to the square 4pin connector that gives 12v to the processor.
Hope that helps
Chris
On Thu, 2005-11-17 at 10:00 +0000, Peter Onion wrote:
Does anyone have any experience with PCI-E graphics cards ?
I've purchased a ATI X800-GTO to put in my new AMD 64 box, but I'm
confused
by what it says on the box ... "Mother board must support specialized
12V
connector for graphics cards" (Or words to that effect).
Now there is space on the graphics card for a 6 pin (2x3) socket but
there
is not one mounted there, so I'm guessing that I don't need to provide
this
particular version of the card with any additional power (other than
what it
can draw from the PCI-E connector).
Any thoughts ?
Peter
Hi Peter,
On both of my PCI Express equipped machines, there is a Harddrive style power connector right next to the PCIE slot which needs a power cable plugged in. This is in addition to the square 4pin connector that gives 12v to the processor.
Hope that helps
Mine has both of them as well, but it's obvious what to plug into them ! :-)
My problem is the box for the graphics card seems to suggest there should be a power connector on the card itself, yet the space is unpopulated.
Peter
The message 20051117090122.GA18892@areti.co.uk from Chris Green chris@areti.co.uk contains these words:
A bigger battery won't take more charging current, it'll just take longer to charge. The internal resistance of just about *any* lead acid battery will be negligable compared with that of the charging circuitry, the charging circuitry will set the current at any given voltage and will not be affected by the (negligable) internal resistance of the battery.
That's what *I* thought, but I used a plug-in lead-acid charger block meant for a burglar-alarm-sized battery to charge a small motorcycle battery - and the charger burnt out.
On Thu, Nov 17, 2005 at 12:25:56PM +0000, Anthony Anson wrote:
The message 20051117090122.GA18892@areti.co.uk from Chris Green chris@areti.co.uk contains these words:
A bigger battery won't take more charging current, it'll just take longer to charge. The internal resistance of just about *any* lead acid battery will be negligable compared with that of the charging circuitry, the charging circuitry will set the current at any given voltage and will not be affected by the (negligable) internal resistance of the battery.
That's what *I* thought, but I used a plug-in lead-acid charger block meant for a burglar-alarm-sized battery to charge a small motorcycle battery - and the charger burnt out.
In that case I'd guess that there was some circuitry in/close to the burglar-alarm-sized battery.
It's also *possible* but rather unlikely that the batteries actually had slightly different chemistry. Apparently some of the latest 'Calcium' car batteries (which are still basically lead-acid) need a slightly different charging voltage.
... or it may just be that the charger was crap and would have burnt out whattever battery you connected it to. I assume by the way that the burglar alarm battery was a 12 volt one, and so was the bike battery.
The message 20051117150105.GA21211@areti.co.uk from Chris Green chris@areti.co.uk contains these words:
On Thu, Nov 17, 2005 at 12:25:56PM +0000, Anthony Anson wrote:
The message 20051117090122.GA18892@areti.co.uk from Chris Green chris@areti.co.uk contains these words:
A bigger battery won't take more charging current, it'll just take longer to charge. The internal resistance of just about *any* lead acid battery will be negligable compared with that of the charging circuitry, the charging circuitry will set the current at any given voltage and will not be affected by the (negligable) internal resistance of the battery.
That's what *I* thought, but I used a plug-in lead-acid charger block meant for a burglar-alarm-sized battery to charge a small motorcycle battery - and the charger burnt out.
In that case I'd guess that there was some circuitry in/close to the burglar-alarm-sized battery.
Just an ordinary lead/acid 12v sealed unit with two tongue connectors, intended in fact, for a burglar alarm. It charged that without demur, but putting it on to a similar type, but larger accumulator borked it.
It's also *possible* but rather unlikely that the batteries actually had slightly different chemistry. Apparently some of the latest 'Calcium' car batteries (which are still basically lead-acid) need a slightly different charging voltage.
This was about six or seven years ago, and both batteries were standard sort of things, one off the shelf from a security firm and the other ditto from a small motorcycle shop.
... or it may just be that the charger was crap and would have burnt out whattever battery you connected it to. I assume by the way that the burglar alarm battery was a 12 volt one, and so was the bike battery.
This is possible, and yes, they were both 12v accumulators.
The delivered voltage of the block was, IIRC, 13·8v
Just to bring you up to date on my privte saga ...
I called World of Computers in Cambridge this morning. Having identified an APC battery (Part No RBC17 = "Replacement Battery Cartridge", official APC part and not an "equivalent") apparently equivalent to the battery for my Belkin UPS, and knowing that WOC sell APC UPSs, I asked them if they sold replacement batteries.
"We might do".
I then gave them the Part No. They looked it up on their database. They located the item, and then:
"I'm sorry, none of our suppliers supply that item."
So, what with Belkin not licenced to sell separate batteries in Europe, and WOC unable to get one from their suppliers, I bit the bullet and set about wiring up the little motorcycle battery (YT4L-BS -- you can find it on the web, and it's apparently meant for the old 125cc Hondas; weighs about 4 lb, so is nice and portable as a mobile laptop PS).
Cut off a yard of lighting-circuit-grade cable, soldered spade connectors to the leads at one and, and ring-terminals to the other. Fixed the latter to the battery terminals (nice solid screws on the battery), and plugged the spades into their female counterparts on the UPS.
Switched on. All apparently OK. Started up one machine and TFT monitor. Still apparently OK. Switched off mains power for a few minutes -- UPS went into "beep" mode,l but the computer didn't miss a breath. So still all normal. Switched on the second machine. Still apparently all OK.
And now, half an hour later, all is still running normally. Cable leads cool to the touch at all times (including the temorary "power failure").
Yet to do: Full test of auto shutdown on "power failure" ( = pull the plug in this case).
But my tentative, and fairly confident, coonclusion is that an itsy bitsy m/c battery will do nicely, at least in emergency.
Now to see if possibly I can buy a real battery from somewhere! mdsbattery.co.uk have the CSB HR 1234 WF2, claimed to be equivalent to the one I'd really like to get, on sale for £13.95, which was about what the m/c battery cost me.
Ah well, I will pull the plug after sending this mail. If you don't hear from me within 24 hours, you'll know that something went badly wrong!
Bye for now ...
Ted.
-------------------------------------------------------------------- E-Mail: (Ted Harding) Ted.Harding@nessie.mcc.ac.uk Fax-to-email: +44 (0)870 094 0861 Date: 17-Nov-05 Time: 20:12:51 ------------------------------ XFMail ------------------------------
On 17-Nov-05 Ted Harding wrote:
Just to bring you up to date on my privte saga ... [...] Yet to do: Full test of auto shutdown on "power failure" ( = pull the plug in this case).
But my tentative, and fairly confident, coonclusion is that an itsy bitsy m/c battery will do nicely, at least in emergency.
Power failure test now done. The upshot is that the UPS, on the m/c battery, decides somewhat prematurely that the battery is too low, and simply switches itself off.
Previously, based on timings (when the old battery was in a good state), I had worked out a shutdown programme such that:
1. If power-off detected, wait 2 min (in case it comes back on)
2. The machine with the serial-port connection to the UPS then sends an email to user "shutdown" on the other machine.
3. The other machine has a root cron job running every minute to check whether "shutdown" has mail. If so, this machine immediately executes "shutdown -h now". This takes maximum 2 minutes. So all over for this machine within 5 min of power outage.
4. Meanwhile, the first machine waits a minute (to allow for latency in sending and delivering the mail), and then itself runs "shutdown -h now". Again a minute or two, so all over within 5 minutes.
5. The UPS itself turns off at about 6 minutes, so there's a margin to ensure that the machines are not without power while shutting down.
With the motocycle battery, the UPS decides that the battery is too low at around 2 minutes, and simply turns itself off. The result is that both machines get caught before shutting down.
I suspect that this may be due to the m/c battery having a naturally slightly lower voltage (12.0v) than the UPS expects from a battery in good nick (with the old battery this would be around 12.5v or even a bit higher), so that "dropping" to 12.0v is taken as a sign of debilitation anyway, and the further drop as current is drawn to supply backup power finally does for it.
I'm pondering workrounds, one of which could be to considerably reduce the 2-minute delay at (1) above. I now have enough experience of local conditions to be aware that a power-out is either a few seconds (less than 20 at a rough estimate) or much longer than two minutes. So I might just manage to squeeze that in. The one I can't do much about is the delay plus cron latency in delivering that email to "shutdown", plus the actual shutdown time for the other machine. That could in total go over 2 minutes, which would bring it dangerously close to being powered off before completion.
Hmmm. It's been an interesting experiment, so far, and I'm obliged to everyone who threw in their opinions asnd experiences.
Best wishes to all, Ted.
-------------------------------------------------------------------- E-Mail: (Ted Harding) Ted.Harding@nessie.mcc.ac.uk Fax-to-email: +44 (0)870 094 0861 Date: 17-Nov-05 Time: 23:20:04 ------------------------------ XFMail ------------------------------
The message XFMail.051117232007.Ted.Harding@nessie.mcc.ac.uk from (Ted Harding) Ted.Harding@nessie.mcc.ac.uk contains these words:
With the motocycle battery, the UPS decides that the battery is too low at around 2 minutes, and simply turns itself off. The result is that both machines get caught before shutting down.
I suspect that this may be due to the m/c battery having a naturally slightly lower voltage (12.0v) than the UPS expects from a battery in good nick (with the old battery this would be around 12.5v or even a bit higher), so that "dropping" to 12.0v is taken as a sign of debilitation anyway, and the further drop as current is drawn to supply backup power finally does for it.
My UPS has accumulators in excess of twelve years old, and while it isn't an all-singing, all-dancing software-controlled one, it still functions effectively, and on the occasions when it has had to allow me to shut down due to a power outage, it hasn't tried any sneaky tricks like that.
How old is the motorcycle battery? Could a cell be down?
On Thursday 17 November 2005 20:12, Ted Harding wrote:
So, what with Belkin not licenced to sell separate batteries in Europe, and WOC unable to get one from their suppliers, I bit the bullet and set about wiring up the little motorcycle battery (YT4L-BS -- you can find it on the web, and it's apparently meant for the old 125cc Hondas; weighs about 4 lb, so is nice and portable as a mobile laptop PS).
One very important thing to note about motorcycle (and most car) batteries is they are not sealed - This means hydrogen will vent to the outside world, and small quantities of sulfuric acid can escape. Your average UPS battery is totally sealed and leak proof (unless damaged).
I bet if you look at http://www.yuasa-battery.co.uk/images/downloads/Y12.pdf there will be one that matches your Belkin.. Highly unlikely that they would use a custom design. With a Yuasa number, you should be able to find any number of suppliers.
Regards, Paul.
On Thu, Nov 17, 2005 at 11:58:42PM +0000, Paul wrote:
On Thursday 17 November 2005 20:12, Ted Harding wrote:
So, what with Belkin not licenced to sell separate batteries in Europe, and WOC unable to get one from their suppliers, I bit the bullet and set about wiring up the little motorcycle battery (YT4L-BS -- you can find it on the web, and it's apparently meant for the old 125cc Hondas; weighs about 4 lb, so is nice and portable as a mobile laptop PS).
One very important thing to note about motorcycle (and most car) batteries is they are not sealed - This means hydrogen will vent to the outside world, and small quantities of sulfuric acid can escape. Your average UPS battery is totally sealed and leak proof (unless damaged).
I bet if you look at http://www.yuasa-battery.co.uk/images/downloads/Y12.pdf there will be one that matches your Belkin.. Highly unlikely that they would use a custom design. With a Yuasa number, you should be able to find any number of suppliers.
I actually have a small sealed lead acid battery that Maplin sent to me by mistake a year or more ago and never collected. It's about 'medium motorcycle' size, free for the cost of postage if you want it. (Or collect from near Ipswich)
On Thu, 2005-11-17 at 09:01 +0000, Chris Green wrote:
A bigger battery won't take more charging current, it'll just take longer to charge. The internal resistance of just about *any* lead acid battery will be negligable compared with that of the charging circuitry, the charging circuitry will set the current at any given voltage and will not be affected by the (negligable) internal resistance of the battery.
I think you may be confusing the charging of lead acid cells with dry cells.
Ideally lead acid cells should be charged with constant voltage not constant current as with most dry cells (actually is not as clear cut as that as some of the more modern dry cell technology requires a sort of constant current/constant voltage hybrid charger that switches modes at different points in the charge)
My point is that a badly designed battery charger for a small capacity lead acid pack could feasibly become damaged by operating beyond it's rated output duty cycle by being connected to a larger capacity pack.
A lot of the better UPS's have smart charging circuitry that cycles the battery (not a deep cycle, just a gentle charge/discharge) and monitors the battery condition based on results from this cycle. I could imagine it getting a little confused if a larger (or otherwise different) pack was connected.
On Fri, Nov 18, 2005 at 11:14:14AM +0000, Wayne Stallwood wrote:
On Thu, 2005-11-17 at 09:01 +0000, Chris Green wrote:
A bigger battery won't take more charging current, it'll just take longer to charge. The internal resistance of just about *any* lead acid battery will be negligable compared with that of the charging circuitry, the charging circuitry will set the current at any given voltage and will not be affected by the (negligable) internal resistance of the battery.
I think you may be confusing the charging of lead acid cells with dry cells.
Ideally lead acid cells should be charged with constant voltage not constant current as with most dry cells (actually is not as clear cut as that as some of the more modern dry cell technology requires a sort of constant current/constant voltage hybrid charger that switches modes at different points in the charge)
The 'constant voltage' is only an indication of how the charger controls the charging current. Unless the charger has a *ridiculously* low internal resistance the voltage will be dictated by the state of charge of the battery and little else.
I agree that lead acid battery chargers are nominally 'constant voltage' as they control their charging current according to the voltage being output and detect a fully charged battery by the voltage. NiCd and NiMh chargers are (basically, but with caveats) constant current devices.
My point is that a badly designed battery charger for a small capacity lead acid pack could feasibly become damaged by operating beyond it's rated output duty cycle by being connected to a larger capacity pack.
I doubt it, the voltage across the battery will be dictated by the state of charge of the battery. It's the *voltage* of the battery while charging that the charger uses to detect how near fully charged the battery is. A 50% charged 100Ah battery will show the same voltage as a 50% charged 10Ah battery (some assumptions of course, similar battery type and construction, similar state of decay, etc.). The charger will push the same current into both, it's just that the voltage of the lower capacity one will rise faster as it gets charged.
A lot of the better UPS's have smart charging circuitry that cycles the battery (not a deep cycle, just a gentle charge/discharge) and monitors the battery condition based on results from this cycle. I could imagine it getting a little confused if a larger (or otherwise different) pack was connected.
Maybe, but the example in question was (as I understand it) a cheap and simple wall wart type charger I think.
On Fri, 2005-11-18 at 12:44 +0000, Chris Green wrote:
The 'constant voltage' is only an indication of how the charger controls the charging current. Unless the charger has a *ridiculously* low internal resistance the voltage will be dictated by the state of charge of the battery and little else.
I agree that lead acid battery chargers are nominally 'constant voltage' as they control their charging current according to the voltage being output and detect a fully charged battery by the voltage. NiCd and NiMh chargers are (basically, but with caveats) constant current devices.
I think perhaps we are talking about the same thing but using different terminology...hence the confusion.
By my understanding.
Most lead acid chargers charge at a constant voltage, a car battery charging circuit will for example charge at a constant 13.8v (or whatever, depending on the delivery capacity of the charging circuit) (12v being the nominal voltage of a car battery) This voltage is output regardless of battery charge condition...naturally the charge current then goes down as the charge progresses (and therefore as you say the battery voltage goes up) Because the output voltage is higher than the nominal voltage of the battery, once charged the offset is calculated to equal a acceptable trickle charge (given the internal resistance of the average battery)
This is one of the (many) reasons why we now use alternators in cars rather than dynamos, it is hard to build a constant voltage charge around a dynamo supply unless the dynamo is running at a constant speed. This is also why a current meter in a modern car is far more useful than a voltage meter.
Most smart charging circuits don't actually measure the battery voltage because this is difficult to do during the charge process. They simply measure charge current and when it hits a low trigger the charge is considered complete. This is important in a fast charger because in order to achieve a fast charge the output voltage may be too high to drop to a acceptably low trickle charge (stick 15 volts into a 12 volt lead acid indefinitely and you will just boil off the acid, which apart from not being too good for the battery, is pretty dangerous in a confined space)
Dumb (quick and dirty) NiCd (and NiMh) chargers operate in the opposite way, you set a hard current limit (for trickle this is usually capacity/10, at least that is what I have set for the charging circuit I have just built for my portable mp3 streamer project). This current limit is held regardless of the internal resistance or voltage of the pack connected, although naturally if the pack voltage gets close to the charge voltage this may drop. You can determine the charge state by looking at the voltage across the pack (even when on charge) with this circuit because your Constant Current circuit will be adjusting the charge voltage to achieve the desired charge current, therefore the higher the charge voltage the nearer you are to full charge.
My point is that a badly designed battery charger for a small
capacity
lead acid pack could feasibly become damaged by operating beyond
it's
rated output duty cycle by being connected to a larger capacity
pack.
I doubt it, the voltage across the battery will be dictated by the state of charge of the battery. It's the *voltage* of the battery while charging that the charger uses to detect how near fully charged the battery is. A 50% charged 100Ah battery will show the same voltage as a 50% charged 10Ah battery (some assumptions of course, similar battery type and construction, similar state of decay, etc.). The charger will push the same current into both, it's just that the voltage of the lower capacity one will rise faster as it gets charged.
Sorry I wasn't very clear, my point was that I bet a lot of the cheaper wall wart chargers are duty cycle limited. Given a constant voltage charge the charger will be delivering the same current at the start of a charge for a 10Ah pack as a 100Ah pack but it will be delivering that maximum current for 10 times as long, given manufactures habits of designing everything down to the minimum this could quite likely result in meltdown.
A lot of the better UPS's have smart charging circuitry that cycles
the
battery (not a deep cycle, just a gentle charge/discharge) and
monitors
the battery condition based on results from this cycle. I could
imagine
it getting a little confused if a larger (or otherwise different)
pack
was connected.
Maybe, but the example in question was (as I understand it) a cheap and simple wall wart type charger I think.
Again that was my fault, I went of on a tangent about different charge methods (from the original subject of connecting a random 12 lead acid battery to a UPS in place of the original pack) and then snapped back on topic without telling anyone. I was in Holiday mode...sorry.
On Sun, Nov 20, 2005 at 08:23:34PM +0000, Wayne Stallwood wrote:
On Fri, 2005-11-18 at 12:44 +0000, Chris Green wrote:
The 'constant voltage' is only an indication of how the charger controls the charging current. Unless the charger has a *ridiculously* low internal resistance the voltage will be dictated by the state of charge of the battery and little else.
I agree that lead acid battery chargers are nominally 'constant voltage' as they control their charging current according to the voltage being output and detect a fully charged battery by the voltage. NiCd and NiMh chargers are (basically, but with caveats) constant current devices.
I think perhaps we are talking about the same thing but using different terminology...hence the confusion.
By my understanding.
Most lead acid chargers charge at a constant voltage, a car battery charging circuit will for example charge at a constant 13.8v (or whatever, depending on the delivery capacity of the charging circuit) (12v being the nominal voltage of a car battery) This voltage is output regardless of battery charge condition...naturally the charge current then goes down as the charge progresses (and therefore as you say the battery voltage goes up) Because the output voltage is higher than the nominal voltage of the battery, once charged the offset is calculated to equal a acceptable trickle charge (given the internal resistance of the average battery)
No, I think this is where we differ. The charger will *attempt* to charge at a constant 13.8 volts (or whatever) but the actual voltage across the battery terminals will be determined by the state of charge of the battery. The charger will (hopefully) be designed so that the charging current reduces to a trickle charge when the battery voltage reaches the desired voltage.
This is one of the (many) reasons why we now use alternators in cars rather than dynamos, it is hard to build a constant voltage charge around a dynamo supply unless the dynamo is running at a constant speed. This is also why a current meter in a modern car is far more useful than a voltage meter.
Alternators are the most 'non constant voltage' thing you could imagine. It's the electronic regulator and rectifiers that have made the use of alternators possible. The one thing that the alternator does that's "clever" is limit the charging current by its internal resistance. The major reason, as I understand it, for the move from dyanamos to alternators is the availability of cheap electronics and the better reliability (because of their simplicity) of alternators compared with dynamos.
Most smart charging circuits don't actually measure the battery voltage because this is difficult to do during the charge process. They simply measure charge current and when it hits a low trigger the charge is considered complete. This is important in a fast charger because in order to achieve a fast charge the output voltage may be too high to drop to a acceptably low trickle charge (stick 15 volts into a 12 volt lead acid indefinitely and you will just boil off the acid, which apart from not being too good for the battery, is pretty dangerous in a confined space)
As I understand it what happens is that the 'fast' charger will be current limited (by it's own internal circuitry) until the battery voltage rises to a voltage which indicates that it is fully charged. You simply *can't* "stick 15 volts into a 12 volt lead acid", the voltage will stay obstinately at whatever voltage is dictated by the state of charge of the battery.
This is certainly what my Gunsons 'automatic' charger says it does in the blurb that comes with it. While the battery voltage is at any voltage significantly less than the voltage indicating fully charged the charger runs at it's maximum current output. Then, as the battery voltage approaches a 'fully charged' voltage, the current reduces. It has two modes then, one which will put a really full charge in the battery but which will make it gas slightly if left connected and one (which stops at a slightly lower voltage) which will not quite fully charge the battery but won't make it gas if left connected. It's very explicit that the charging current is determined by voltage, that's how it can be used an just about *any* capacity of lead acid battery. As long as the battery can cope with (for this particular charger) a charging current of around 8 amps then it will work. Any discharged lead-acid battery connected to it will get 8 amps pushed into it initially.
Dumb (quick and dirty) NiCd (and NiMh) chargers operate in the opposite way, you set a hard current limit (for trickle this is usually capacity/10, at least that is what I have set for the charging circuit I have just built for my portable mp3 streamer project). This current limit is held regardless of the internal resistance or voltage of the pack connected, although naturally if the pack voltage gets close to the charge voltage this may drop. You can determine the charge state by looking at the voltage across the pack (even when on charge) with this circuit because your Constant Current circuit will be adjusting the charge voltage to achieve the desired charge current, therefore the higher the charge voltage the nearer you are to full charge.
Yes, simple NiCd and NiMh chargers are designed to run at a constant current of capacity/10 (or better for long life capacity/14) because the batteries will survive this rate of charge for a long time without damage even if they're already fully charged.
I doubt it, the voltage across the battery will be dictated by the state of charge of the battery. It's the *voltage* of the battery while charging that the charger uses to detect how near fully charged the battery is. A 50% charged 100Ah battery will show the same voltage as a 50% charged 10Ah battery (some assumptions of course, similar battery type and construction, similar state of decay, etc.). The charger will push the same current into both, it's just that the voltage of the lower capacity one will rise faster as it gets charged.
Sorry I wasn't very clear, my point was that I bet a lot of the cheaper wall wart chargers are duty cycle limited. Given a constant voltage charge the charger will be delivering the same current at the start of a charge for a 10Ah pack as a 100Ah pack but it will be delivering that maximum current for 10 times as long, given manufactures habits of designing everything down to the minimum this could quite likely result in meltdown.
It could do I suppose but I would have thought most small chargers reach thermal equlibrium long before the battery they're charging, whatever its capacity, has been charged. I suppose being hot for 20 hours will be more likely to kill the charger than being hot for 2 hours but I doubt if the temperature reached will be much different.
On Wed, Nov 16, 2005 at 03:08:36PM -0000, Ted Harding wrote:
Hi Folks,
Can anyone recommend a good place to look for a UPS within reasonable reach of Ely?
I've been running a Belkin 625VA "Regulator Pro Gold" very happily for some 4 years, but unfortunately its battery is now going dodgy.
In view of Belkin's approach to battery replacement, I now want to simply replace the whole UPS.
Another option would be to replace the battery with one from someone like http://www.mdsbattery.co.uk/ (Brett reminded me of them on IRC) it will probably work out quite a bit cheaper than replacing the UPS.
Adam
On 16-Nov-05 Adam Bower wrote:
On Wed, Nov 16, 2005 at 03:08:36PM -0000, Ted Harding wrote:
Hi Folks,
Can anyone recommend a good place to look for a UPS within reasonable reach of Ely?
I've been running a Belkin 625VA "Regulator Pro Gold" very happily for some 4 years, but unfortunately its battery is now going dodgy.
In view of Belkin's approach to battery replacement, I now want to simply replace the whole UPS.
Another option would be to replace the battery with one from someone like http://www.mdsbattery.co.uk/ (Brett reminded me of them on IRC) it will probably work out quite a bit cheaper than replacing the UPS.
Thanks! I've just been looking at their website, as it happens (popped up on a google for "BB Battery HR9-12" which is what it says on my UPS battery); mdsbattery say that the CSB HR 1234 WF2 is "equivalent to" the HR9-12. £13.95 inc. VAT (plus, by the look of it, £6.50 shipping charge). Definitely cheaper that a new UPS! Official battery for APC UPSs, it seems.
Which leads me now to wonder if WOC in Canmbridge (as pointed out by Tim Green) might supply the battery, since they sell APCs. I must check with them tomorrow.
Hmmm. These threads are leading everywhere. Thanks, all, and if you've got more interesting ideas I'd be intrigued to hear.
Best wishes, Ted.
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