1975 Argosy inverter

[Ibcosmo]

Hi, the inverter in my 1975 Argosy makes a heck of a humming noise. Thought maybe just working hard to charge a run down battery, but not the case. My question is, is this normal for this year and model and is replacement required? The inverter is a Triad-Utrad model TU-331W converter charger. If replacement is necessary with what do I replace it with? Thanks, Cosmo

[DKB_SATX]

You're talking about a CONverter, not an inverter. Commonly referred to as a "Univolt" on trailers the vintage of ours.

It's pretty common for Univolts to hum, because of the way they work. It'll probably keep getting louder until it eventually just stops humming (and at the same time stops working) but that may not be anytime soon.

The worst thing about the old Univolt is that it's hard on batteries if you leave the trailer plugged in for days. It doesn't back off when the battery is fully charged, so it'll boil the electrolyte, shortening the life of the battery.

A modern 3- or 4-stage 45-amp converter-charger is around $140-$170 dollars. The one I recently installed is a PowerMax brand, purchased through BestConverter. I'm happy with the results. People also seem to be universally happy with the performance of Iota and Progressive Dynamics converter-chargers.

[Ibcosmo]

Thanks for the help. Went to there website looks pretty simple to upgrade. Thanks again, Cosmo

[poldaddy]

I am in the process of replacing my uni-volt on my 75 Land Yacht with a nrw converter. I have a question on the back side of the low voltage dist panel there are 2 larger post that were wired to the uni volt. i had assumed one pos one neg but it appears both are positive??? Anyone have any input

[azflycaster]

The two large posts are positive (red wire - upper connector) and negative (black wire - lower connector).

The unitvolt would have had 3 output wires,one of which was much smaller in diameter then the other two. That wire was for the power on light. Replacement converters do not have this power on light.

This is how my 75 TW is wired.