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which generator circuit is better/costs less to charge an SLA?? Answered

which generator circuit is better/costs less to charge an SLA??
please see the three circuits below and vote but if you think you can improve one of them please email me , I will post it and do the leg work.
 I am about to retire and my purpose is to at least not pay for the reading lights..
Thanks for your input


You can't put 60 V on an LM317 !

A SLA likes constant voltage charging at ~2.22 V/cell, so an LM317 and a circuit like this one http://www3.telus.net/chemelec/Projects/Charger/Charger.htm is a darned good idea. It isn't going to cost a lot either.

Make sure your battery bank can't get too cold, or too hot.

Even so, if you have a really variable input, you could do with some way to dump the excess energy somewhere useful, and a way of switching heaters in your hot water heater would also save you money.


shhhhh...yes you can. see lm317HV. it's close, but I know they work @60VDC. One can always use a few hefty diodes in series with the input if one is worried about the approach to the max input, or simply drop the input voltage to say, 55VDC. to ensure uninterrupted operation..

Wooo. Never seen that before. Thanks for that one Sean. Steve

np Steve.

It's nice to have when you can't get by with a 30-ish V supply but you do have higher. At one time, I think there was an even higher rated part, although my memory fails me on specifics. May have been mil spec. (this was at least 10 years ago)

razzafrazza...nocolor in the rich t editor. does it take that much bandwidth?

Transistor for switching the charging off. this is unique as far as SLA chargers on instructables usually simplistic.

In the middle drawing using a solar cell, what is the transistor for. Couldn't you do this with just a diode?

I've forgotten what an SLA is.