Boilers??????

Can I point out that the bulk of UPS chargers are SCR based and charge
batteries at 400v (ish) if the battery voltage is maintained at 2.25-2.27
vpc the battery design life is often obtained if the battery temperature is
kept in the 18-22 deg window. Automotive batteries and chargers are not
built to the same quality of materials as standby batteries and their
chargers. There is product available now with a 15 year design life for a
sealed (VRLA) battery. Typical automotive construction materials would not
expect to see more that about 4 years life for the battery. 

Rgds Steve..

-----Original Message-----
From: piclist-bounces@mit.edu [mailto:piclist-bounces@mit.edu] On Behalf Of
Steph Smith
Sent: 08 January 2006 01:51
To: piclist@mit.edu
Subject: [EE]Sealed Lead Acid Charger

All of the newer chargers i've pulled apart (well you HAVE to!)
i.e not the bridge rec. and SCR 'boilers' of yore,contain charge 
management I.C.'s of some description;even in the cheapest
domestic 'home' car chargers.(the main cost in producing a
charger is the cost of the transformer)These usually take care of 
problems such as shorted cells (won't charge) reverse 
connections(won't charge) sulphated plates (wont charge)
indeed they are so 'paranoid' i keep a 'kick-in-the-pants'
old fashioned charger to recover batteries to a state in which
newer ones will take over without switching off constantly!
One one memorable occasion i used the boost-start
setting (140A!)and flicked the power on and off to 
revive a 650Ah 12v van battery which had gone totally 'flat'.
Although i wouldn't recomend it; it remained in use for six months
and was still in the van when i sold it...i think experiments like this 
prove one thing at least; Batteries CAN'T READ;^) 
-- 
http://www.piclist.com PIC/SX FAQ & list archive
View/change your membership options at
http://mailman.mit.edu/mailman/listinfo/piclist

-- 
http://www.piclist.com PIC/SX FAQ & list archive
View/change your membership options at
http://mailman.mit.edu/mailman/listinfo/piclist