UPS True Sine Wave Inverter Ready to mount

[Christian]

Well I have finished the mods for the UPS I was modifying.

[DW SD]

Christian,
does the fact that the UPS is 48V mean that you cannot use those batteries to run 12V appliances in the rest of the coach? Seems like a good deal, but limiting if you are carrying those batteries just to run the UPS / inverter.

Doug

[Christian]

Originally Posted by DW SD

Christian,
does the fact that the UPS is 48V mean that you cannot use those batteries to run 12V appliances in the rest of the coach? Seems like a good deal, but limiting if you are carrying those batteries just to run the UPS / inverter.

Doug

In short no.
You could incorporate a series of 3 phase breakers/relays/plugs to isolate and reconnect the bank back to 12 volt to power the MH house..the plugs would be the cheapest and would require rewiring in a pinch. I have over sized the banks and have a set for 12 volt and a set for 48volt the 48 volt is under the curbside bed behind the electric heater and under the drawer this was dead space anyway so I don't figure I lost anything but weight..
I wanted a spare AGM pack in the warmth in case I needed to start the motor or Genny with a boost from the 120v chargers.... or a direct connect...

[DW SD]

Gotcha, sounds like you are using them exactly as I had thought...connected in series at 48V. Of course, in a pinch, you could reconfigure or use a more complicated set of relays / switches to reconfigure.

That wasn't really my question.

Clever use of your resources and technology nonetheless and thank you for the explanation! Fine job!

Doug

[MRPutz]

Originally Posted by Christian

But The good thing is it does not require the current of a 12 volt unit. Also the batteries can be changed with new ones as they become weak since they are all 4 in series.... 1 bad one won't kill them all. Can't do any of that with parallel packs.....

I'm not sure I understand your statement.

Batteries in series are vulnerable to bad batteries. If a battery shorts you're down to 36v, if a battery opens you have 0v as they are in series.

The only difference between series and parallel is that the out come is reversed for the same battery issues.

Batteries in parallel are vulnerable to bad batteries also. If a battery shorts you're down to 0v and it drags down the other batteries, if a battery opens you have 12v as they are in parallel.

Did I miss something you stated?

[Christian]

Originally Posted by rtpn60

I'm not sure I understand your statement.

Batteries in series are vulnerable to bad batteries. If a battery shorts you're down to 36v, if a battery opens you have 0v as they are in series.

The only difference between series and parallel is that the out come is reversed for the same battery issues.

Batteries in parallel are vulnerable to bad batteries also. If a battery shorts you're down to 0v and it drags down the other batteries, if a battery opens you have 12v as they are in parallel.

Did I miss something you stated?

No I think you have the point. The UPS will disconnect at 42 volts. Also when open condition happens the unit will open.
A bad battery in series will not kill the others in series. In paralell it will kill the others. Neither condition will continue operational while in a faulty condition.

[MRPutz]

Thanx Richard.. We're on the same page.