Is It Normal For A Small Residual DC Charge To Stay On The Inverter Terminals?

[RobertM]

I tested a switch that connects 2 battery banks  to the inverter.  When the switch is on the full battery voltage is present at the DC terminals. When the switch is off, even after the inverter is discharged, there is about a 1V reading at the terminals. I'll test it again later, maybe it dissipates over time?

 

 

 

[Sid Genetry Solar]

54 minutes ago, RobertM said:

When the switch is off, even after the inverter is discharged, there is about a 1V reading at the terminals. I'll test it again later, maybe it dissipates over time?

So the discharge decay will be sorta logarithmic.  The lower the voltage goes, the fewer electronic circuits can function--so like you've found, down at 1v, it may keep that voltage for days on end.  Good capacitors will literally hold a charge for months if there's no external discharge factors at play.

I don't see how 1v could be an issue though.

[RobertM]

29 minutes ago, Sid Genetry Solar said:

 

I don't see how 1v could be an issue though.

I assumed that dc voltage would quickly go to zero if there was no input, and I had "discharged" the inverter. As long as it's normal, I'm happy.

[Sid Genetry Solar]

Not many things work below 2-3v (yeah, I know, computer CPUs often run at 1v or less, but that's different!) meaning that there's nothing much to discharge the caps all the way to zero.  A bleeder resistor would do that--but there aren't any (per se!) in the GS inverters.

And yes, it's perfectly normal.