parallax power supply 7345ru parts PWM
My 7345 is not charging the coach batteries but does supply 12power to all accessories. The transformer, fan and relays work fine. Think i need a PWM circuit for it. Contacted PP tec support and th...
Forum Discussion
Cstoliker wrote:
... and the voltage does increase with load, ...
Did you mean increase with load, or decrease with load?
I've never seen my Parallax 7345's voltage go up with load. It does just the opposite ... goes down with load. That's why I've never seen it supply anywhere near 45 amps into our AGM batteries - because when charging them, the 7345's output voltage isn't at it's nominal output of 13.8 volts - it's always lower. If it stayed closer to 13.8 volts all the way up to 45 amps it would charge my AGM batteries quite fast - because these kind of batteries charge faster than regular wet RV batteries at all charging voltages. I wish my 7345 would hold 13.8 volts at 45 amps.
By the way, it's probably quite common for many/most chargers to not be able to hold their maximum advertised terminal voltage when supplying their maximum advertised current. I wonder how many multi-stage chargers can supply their full current while simultaneously holding their full boost voltage at the same time when charging a large battery bank that starts out at, say 50% state of charge? It's of course possible to build a power supply that can do this ... but it does cost $$$ to pull it off.
I actually would prefer a Parallax 7345 converter in my RV that they no longer make. It was called their 7345T model. It would hold around 14.4 volts for the first four hours after powering it up, then revert to 13.8 volts from then on. This would have been perfect for my particular batteries - as their recommended float voltage is 13.5 volts to 13.8 volts and their recommended fast-charge voltage is 14.4 volts to 14.8 volts.
