Inverter voltage problem

[uemjg]

I just hooked up my house batteries to my inverter and checked output voltage and it is low...around 101vac.

I believe it may have to do with the ground portion of the inverter...I have the inverter's ground connected to the lower compartment's aluminum floor.  Could this be the problem?

[viento1]

is it a pure sine wave inverter? can you test the voltage under load?  The reason I ask is my old square wave would always show a wacky voltage. I have heard that my volt meter was not RMS but I never checked that.

[uemjg]

I don't believe its a pure sine wave...quote from online manual, "Maintains PWM sine wave output voltage of 120V AC (+/-5%)."

I remember the same problem when I wired my garage sub-panel and it was because I didn't have a ground back to the main house panel.  I wondered if this may also be the same issue.

[thomasinnv]

As Viento1 said, if it is MSW and not PSW then it will read low like that with most meters. There is a certain type of meter that will read MSW correctly, don't remember the type off hand though. 100v sounds about right for MSW on fully charged batteries, will go down to about 90 or so as the batteries discharge. Thats with most types of standard volt meters.