DC inverter - battery bank?

[michaelp]

I have the following tripp-lite inverter:
http://www.tripplite.com/en/products/model.cfm?txtSeriesID=818&txtModelID=2938

I haven't used it before but just hooked it up to a SEALED AGM battery (I'm in an office setting).

My office building is telling me they *may* have to turn the power off this weekend and don't know when it would be back on and that they are going to close the building. They also told me they might not turn off the power to our floor. I'm clarifying this, but let's assume there's some probability of no power for a few hours.

1. Does anyone know if I hook the batteries up in parallel or in series? I believe I would want parallel (pos -> pos, neg -> neg).
2. I currently have only one battery hooked up and it's brand new and the inverter is saying the battery only has 20% charge, and won't run the pump when I pull the AC power (yet the lights stay on the inverter, so I know its getting power from somewhere). Anyone have any recommendations?

 

[qy7400]

Parallel will give you the longer run times at same voltage, 2 12v 75ah in parallel will look like 1 12v 150ah to the inverter.

Did you setup the inverter? according to the manual there is a dip switch that needs to be set for AGM batteries. Did you set the operation switch to auto?

 

[michaelp]

Yes, I set that switch. Called tripp-lite as well.

I'm going to test the battery with a voltmeter now and will update.

UPDATE: battery putting out less than 10V. new battery too. at least its under warranty.

 

[jrobbins]

do you have to charge the battery before you use it?