Re: [Repeater-Builder] Batteries in Parallel
Hi guys. I have been watching this backup battery discussion. We use Eastpen Geltech batteries from the states they are the best batteries no weekly monthly maintenance. We check them for capacity every 6 months and thats it. We use a product called Korode Kure on the battery terminals this keeps them clean and a good contact for many years. I have been using this for 30 years. I also use it under HF mobile whip bases. If really stuck out in the bush with a empty tube of KK I have used copper kote a nut and bolt antiseaze.Oh by the way I have had a unsealed battery bank go up so please venterlate the battery box to the outside world and keep a minimum 20 liter bottle of distiled water close at hand in the hut just in case. A 8hr + drive to medical help with acid burns is no fun. Cheers form down under. - Original Message - From: "Mark A. Holman" <[EMAIL PROTECTED]> To: Sent: Thursday, August 25, 2005 8:42 PM Subject: Re: [Repeater-Builder] Batteries in Parallel > As a sugguestion, if the wire has any green corrsion I would replace the > stuff with new, especially if that wire got hot , from my experience. > Mark AB8RU > > Tony VE6MVP wrote: > >>At 12:42 AM 2005-08-25 -0400, you wrote: >> >> > Those BCI -31's are good batteries, you can add extras on if >> >you need to but you would have to go to a HD Truck Parts place or >> >dealership to make up a special 2 or more battery cable, your cable >> >should be #6 or larger diameter ( #4 ,or #0 ) depends on how much >> >current the system is drawing.. >> >>All that was attached to those radios were 2 UHF linking radios wired back >>to back. So the most power they would use would be, guessing 20 amps, >>when one radio is transmitting. I have no idea what gauge of wire was >>used. They'd been there for at least five or ten years if not even >>fifteen or twenty. I say 20 amps because 22 amps was what an >>electrical >>place told me my mobile radio was consuming when we were stress testing >>the >>alternator and battery in my car. >> >>And the other ham was far, far more experienced with all this than I am. >>I >>was basically just the driver and gopher. >> >>Tony >> >> >> >> >> >> >> >> >>Yahoo! Groups Links >> >> >> >> >> >> >> >> >> >> >> > > > > > > Yahoo! Groups Links > > > > > > > Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/Repeater-Builder/ <*> To unsubscribe from this group, send an email to: [EMAIL PROTECTED] <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
Re: [Repeater-Builder] Batteries in Parallel
Seems like an exageration to me. Most likely outcome would be that the system would continue to overheat until both batteries went below 11 volts. Possibly the charger would blow a fuse or burn out. IF you call that a fire..ok. I have seen a battery explode when there was not much electrolyte left and a large amount of current was applied to it. I guess a spark between the plates ignited hydrogen generated from the gassing of the remaining electrolyte and as the caps were still on it blew a corner out of the case. Tony VE6MVP <[EMAIL PROTECTED]> wrote: At 01:12 AM 2005-08-24 +, you wrote:>Can anyone relay any real life experiences with this?To add to the many other comments I recently drove a ham to a remotish link radio site and helped him a bit with replacing the batteries. They were two auto batteries from totally different manufacturers. One was so hot you could barely touch it. The other was room temperature. The battery charger had gotten very hot as well. So much so it was uncomfortably warm to the touch five minutes later. The ham, who has vastly more experience than I do, stated there could've been a fire within days.The two batteries were replaced with a highway truck sized battery which was the same size as the two previous batteries put together.TonyYahoo! Groups Links<*> To visit your group on the web, go to:http://groups.yahoo.com/group/Repeater-Builder/<*> To unsubscribe from this group, send an email to:[EMAIL PROTECTED]<*> Your use of Yahoo! Groups is subject to:http://docs.yahoo.com/info/terms/__Do You Yahoo!?Tired of spam? Yahoo! Mail has the best spam protection around http://mail.yahoo.com YAHOO! GROUPS LINKS Visit your group "Repeater-Builder" on the web. To unsubscribe from this group, send an email to: [EMAIL PROTECTED] Your use of Yahoo! Groups is subject to the Yahoo! Terms of Service.
Re: [Repeater-Builder] Batteries in Parallel
As a sugguestion, if the wire has any green corrsion I would replace the stuff with new, especially if that wire got hot , from my experience. Mark AB8RU Tony VE6MVP wrote: >At 12:42 AM 2005-08-25 -0400, you wrote: > > > Those BCI -31's are good batteries, you can add extras on if > >you need to but you would have to go to a HD Truck Parts place or > >dealership to make up a special 2 or more battery cable, your cable > >should be #6 or larger diameter ( #4 ,or #0 ) depends on how much > >current the system is drawing.. > >All that was attached to those radios were 2 UHF linking radios wired back >to back. So the most power they would use would be, guessing 20 amps, >when one radio is transmitting. I have no idea what gauge of wire was >used. They'd been there for at least five or ten years if not even >fifteen or twenty. I say 20 amps because 22 amps was what an electrical >place told me my mobile radio was consuming when we were stress testing the >alternator and battery in my car. > >And the other ham was far, far more experienced with all this than I am. I >was basically just the driver and gopher. > >Tony > > > > > > > > >Yahoo! Groups Links > > > > > > > > > > > Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/Repeater-Builder/ <*> To unsubscribe from this group, send an email to: [EMAIL PROTECTED] <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
Re: [Repeater-Builder] Batteries in Parallel
At 12:42 AM 2005-08-25 -0400, you wrote: > Those BCI -31's are good batteries, you can add extras on if >you need to but you would have to go to a HD Truck Parts place or >dealership to make up a special 2 or more battery cable, your cable >should be #6 or larger diameter ( #4 ,or #0 ) depends on how much >current the system is drawing.. All that was attached to those radios were 2 UHF linking radios wired back to back. So the most power they would use would be, guessing 20 amps, when one radio is transmitting. I have no idea what gauge of wire was used. They'd been there for at least five or ten years if not even fifteen or twenty. I say 20 amps because 22 amps was what an electrical place told me my mobile radio was consuming when we were stress testing the alternator and battery in my car. And the other ham was far, far more experienced with all this than I am. I was basically just the driver and gopher. Tony Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/Repeater-Builder/ <*> To unsubscribe from this group, send an email to: [EMAIL PROTECTED] <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
Re: [Repeater-Builder] Batteries in Parallel
I just had an experience at work with battery problems. I work for a wireless company and we use 105 amp lead acid cells in a series-paralel configuration, 12 volt cells, three 48 volt strings. I was at the site last week and detected the smell (and taste) of overcharging batteries. I learned a trick in my old "Bell Head" days to open my mouth and inhale while in the battery room of central offices. This was taught to me by and old time technician. If a battery is overcharging, you will detect a strange taste on your tongue that you learn to remember, that also warns you of the possibility of explosive gasses in the area. In the cellsite, I found one of the 48 volt strings very warm and the battery cases of all 4 batteries buckling and swelling. A voltage test showed one battery reading 10.5 volts instead of 13.5 volts. This indicated a shorted cell in that 12 volt battery. I ventilated the room, put on safety glasses, and disconnected the sting from the other two strings. The entire string will have to be replaced. This is an example of what can happen to a series battery. I would discourage you from using parallel batteries on a repeater, one large battery would be a much better and safer choice. We do use parallel batteries at work, but routine maintenance is required to keep them safely operating. 73, Joe, K1ike goodyk3ng <[EMAIL PROTECTED]> wrote: > Greetings, > > I'm curious if anyone has experience paralleling deep cycle batteries > for a repeater backup. Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/Repeater-Builder/ <*> To unsubscribe from this group, send an email to: [EMAIL PROTECTED] <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
Re: [Repeater-Builder] Batteries in Parallel
It's perfectly okay to parallel large batteries, with one important caveat: They should be identical in every way, preferably from the same lot number. Most large uninterruptible power systems use series-parallel strings of batteries, with very high reliability. I oversee the operation of two 50 kVA UPSs where I work, and each of them has two strings of 40 sealed lead-acid batteries in parallel. That's about 550 VDC per string, and represents a very large energy source. When these batteries reached four years of age, all 160 batteries were replaced at one time, and all were from the same lot. This is critical when you have only two 12 VDC batteries in parallel. Even if you had two batteries with the same part number, but one was a few months older than the other, the internal resistances and charge/discharge characteristics will not match- and one battery will carry significantly more load than the other. Don't even think about paralleling two different brands or sizes of batteries! 73, Eric Lemmon WB6FLY goodyk3ng wrote: > Greetings, > > I'm curious if anyone has experience paralleling deep cycle batteries > for a repeater backup. I'm designing a battery disconnect circuit > that will open a relay if it detects over voltage, or if the > batteries discharge to a low voltage threshold. I'm also going to > liberally fuse everything. Float voltage will be provided by a > modified Astron 50 Amp supply. > > I'm aware of the math to determine backup time and the care and > feeding of lead acid batteries, but I have a concern with paralleling > multiple batteries. I'm worried that if we have one battery go soft, > it will draw current and eventually boil off its electrolyte or worse, > overheat. > > Can anyone relay any real life experiences with this? > > Thanks and 73 > Goody > K3NG > > > Yahoo! Groups Links > > > > Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/Repeater-Builder/ <*> To unsubscribe from this group, send an email to: [EMAIL PROTECTED] <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
[Repeater-Builder] Batteries in Parallel
Greetings, I'm curious if anyone has experience paralleling deep cycle batteries for a repeater backup. I'm designing a battery disconnect circuit that will open a relay if it detects over voltage, or if the batteries discharge to a low voltage threshold. I'm also going to liberally fuse everything. Float voltage will be provided by a modified Astron 50 Amp supply. I'm aware of the math to determine backup time and the care and feeding of lead acid batteries, but I have a concern with paralleling multiple batteries. I'm worried that if we have one battery go soft, it will draw current and eventually boil off its electrolyte or worse, overheat. Can anyone relay any real life experiences with this? Thanks and 73 Goody K3NG Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/Repeater-Builder/ <*> To unsubscribe from this group, send an email to: [EMAIL PROTECTED] <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
