Replacing a converter/charger with an inverter - Page 2

boywonder · 12-17-2013, 07:36 AM

My neighbor is shopping for an inverter/charger now. We'll report back once it's installed.

Thanks everyone, thanks daveb!

boywonder · 01-30-2014, 05:34 PM

Posted the follow-up for this thread......

My neighbor picked up a Tripp-Lite 2000W MSW inverter/charger and the optional remote panel.

We wired a 10' run of 2/0 wire from the house batteries (a pair of 200AH AGMs) to the inverter with a 200A Blue Sea circuit breaker in the positive lead at the batteries. We selected a 200A breaker since at full output the inverter will be drawing 166A at 12V (2000W).

The final wiring was somewhat different than what I posted above (what was I thinking??) and is shown here:

It was really quite simple as we just put the 110VAC pass-thru part of the inverter before the transfer switch.

We initially had a 200A fuse in the + lead instead of a circuit breaker, and when running the microwave (1800W input) the battery voltage would sag to around 11.4V. Looking at the giant 2/0 wire we ran, and seeing the tiny filament in the fuse prompted the switch to a circuit breaker. Now the voltage sags to around 12V when running the micro with fully charged batts.

Works fine so far...

Scalf77 · 01-30-2014, 07:50 PM

I would have thought that you would have wanted the auto switch for the generator to be on the input side of the inverter. In that way you could use the generator to charge the battery. It appears to me that in this configuration the when running the generator you are just going the receptacles.

Greg

boywonder · 01-30-2014, 08:10 PM

Quote:

Originally Posted by Scalf77

I would have thought that you would have wanted the auto switch for the generator to be on the input side of the inverter. In that way you could use the generator to charge the battery. It appears to me that in this configuration the when running the generator you are just going the receptacles.

Greg

Good point.....easy enough to switch a couple of wires; they are all under the dinette.......

boywonder · 02-01-2014, 10:49 PM

Well.....we rewired the inverter per the right image in my first post above (inverter after transfer switch), and with the generator running the microwave it's too much load. Very weird...

IIRC the on-board generator is an onan 2000W. My only thought presently is that the generator cannot support the current draw of the microwave and the inverter charging the batteries simultaneously. We have the dip switches on the inverter set for "mellow" (25A max) charging.

When you press "start" on the MW (1800W input), it shuts down like a breaker is popping then something resets and the display comes back.

**daveb** · 02-03-2014, 05:21 PM

Usually the watt rating is lower than it actually pulls. So a 1800w MW pulls more than 1800 watts. Why such a large microwave? Did the generator once run it?

boywonder · 02-03-2014, 05:51 PM

Dave, 1800W is the input rating of the MW.............from the data label.

**daveb** · 02-03-2014, 06:26 PM

Do an amp check. My guess is it's probably pulling around 15-16 amps depending on line voltage.

boywonder · 02-03-2014, 08:27 PM

The puzzling part is that the micro works fine on the generator with the inverter and generator wired into the transfer switch, but when we move the inverter after the switch, the gen won't run the inverter.

One would think that the inverter is just in "pass thru" mode when on shore power (or generator power when wired after the switch, same thing as far as the inverter is concerned), although it will also use shore (or generator) power to charge the batteries.

The generator also ran the microwave pre-inverter with the converter installed.

If we consider the portion of the power going to charge the battery (25A max with present dip switch setting), it's as much as 300W or probably more depending on how inefficient the charger portion of the inverter is.

So 1800W +300W =2100W, possibly more depending on charger efficiency. I would expect a 2000W rated generator to handle 2100W for more than a few milliseconds. Perhaps the inrush current is spiking?

Dave-yes, measuring the various currents would quantify where the juice is flowing, although I doubt that I could talk the neighbor into re-wiring the inverter once again.

Since we have recently installed solar, he is happy with solar, alternator and shore power being able to charge the batts.

**daveb** · 02-03-2014, 09:33 PM

You've checked and verified the AC polarity throughout the vehicle from device to device and all the plugs including shore power plug? How does the inverter mark the AC hot-neutral-ground? Same with the transfer switch and generator. Hard to say W/O being there and seeing it. Maybe try a lighter load than the MW like a hair drier or space heater.