Electric issue

dwall · 07-11-2020, 02:10 PM

Getting ready for a trip I noticed an issue with my electrical. With everything turned off I turn on one light and it is dim like battery is drained and converter not working. Turn on A/C and lights get bright. Checked the voltage on converter and it’s not charging until a major AC voltage is applied ( A/C, Coffee pot, electric heater etc). If I leave at least one light on everything is fine. Hope this makes sense. Bad converter?

**chuckster57** · 07-11-2020, 02:17 PM

What is the voltage at the battery(s) with the shore cord plugged in? Should be 13+ VDC. If it passes, then I would be looking at the battery.

dwall · 07-11-2020, 02:19 PM

Quote:

Originally Posted by chuckster57

What is the voltage at the battery(s) with the shore cord plugged in? Should be 13+ VDC. If it passes, then I would be looking at the battery.

13.6. Battery is brand new. Checks good with battery tester.

dwall · 07-11-2020, 02:29 PM

Quote:

Originally Posted by dwall

13.6. Battery is brand new. Checks good with battery tester.

Just thought of something else. This didn’t start until I changed all my bulbs to LED. ???

**chuckster57** · 07-11-2020, 02:29 PM

I’ve seen bad batteries brand new. Unplug, let it sit for an hour and then test for voltage and load test it.

dwall · 07-11-2020, 02:33 PM

Quote:

Originally Posted by chuckster57

I’ve seen bad batteries brand new. Unplug, let it sit for an hour and then test for voltage and load test it.

I understand but I checked battery after it has been unplugged and battery switch off for about 5 hours.

**chuckster57** · 07-11-2020, 02:33 PM

Did you load test it?

dwall · 07-11-2020, 02:36 PM

Quote:

Originally Posted by chuckster57

Did you load test it?

Yes sir. With an automotive battery tester.

**chuckster57** · 07-11-2020, 02:51 PM

If you used a 500amp load tester and it passed, I would use a hydrometer on each cell.

Gord · 07-11-2020, 03:24 PM

Quote:

Originally Posted by dwall

Getting ready for a trip I noticed an issue with my electrical. With everything turned off I turn on one light and it is dim like battery is drained and converter not working. Turn on A/C and lights get bright. Checked the voltage on converter and it’s not charging until a major AC voltage is applied ( A/C, Coffee pot, electric heater etc). If I leave at least one light on everything is fine. Hope this makes sense. Bad converter?

A couple of questions about your shore power connection, is it a 30amp, 50amp or possibly plugged into a 15amp outlet?
Possible you meant it's not charging until a major AC (120V) load is turned on.
I believe your issue may be on the 120VAC side of things. If you have a 50amp service at 240VAC it is possible to have an open neutral in the main supply and show the symptons you are describing

dwall · 07-11-2020, 04:39 PM

Quote:

Originally Posted by Gord

A couple of questions about your shore power connection, is it a 30amp, 50amp or possibly plugged into a 15amp outlet?
Possible you meant it's not charging until a major AC (120V) load is turned on.
I believe your issue may be on the 120VAC side of things. If you have a 50amp service at 240VAC it is possible to have an open neutral in the main supply and show the symptons you are describing

It is a 30 amp shore power at my house. I had the same problem at the last campsite we were on.

**JRTJH** · 07-11-2020, 05:00 PM

Plug the trailer into shore power, disconnect the battery and test the battery cable connectors for 13.6 VDC. If it is less than that, the converter is bad. If you test it with the battery connected to the cable connectors, you're reading the battery output PLUS the converter output. You want to confirm the converter is producing 13.6 VDC, so you need to isolate the converter to check it.

If you have recently replaced the battery, you may have blown the reverse polarity fuses in the converter. Any "momentary reverse polarity" will blow those fuses, even a "split second" is too long.

Gord · 07-11-2020, 05:02 PM

Just out of curiosity if you turn off the circuit breaker that feeds your converter do the A/C or coffee maker still work?

dwall · 07-11-2020, 05:10 PM

Quote:

Originally Posted by Gord

Just out of curiosity if you turn off the circuit breaker that feeds your converter do the A/C or coffee maker still work?

Have not tried that. I’ll check that tomorrow.

Gord · 07-11-2020, 05:23 PM

I would definitely suggest that you follow John's reply about the reverse polarity fuses.

**JRTJH** · 07-11-2020, 05:34 PM

Quote:

Originally Posted by Gord

I would definitely suggest that you follow John's reply about the reverse polarity fuses.

Especially after post #3, "Battery is brand new"... I can't begin to count how many owners have blown the reverse polarity fuses and "swear that the battery was NEVER connected wrong".....

dwall · 07-11-2020, 05:35 PM

Quote:

Originally Posted by Gord

I would definitely suggest that you follow John's reply about the reverse polarity fuses.

I will check that also.

**chuckster57** · 07-11-2020, 05:37 PM

Quote:

Originally Posted by JRTJH

Especially after post #3, "Battery is brand new"... I can't begin to count how many owners have blown the reverse polarity fuses and "swear that the battery was NEVER connected wrong".....

I didn’t catch that. Spent the morning in direct sun (got to 102) changing a timing belt/water pump in a Honda. My tools were almost too hot to grab. I know I drank what seemed to be 10 gallons of water so my brain may have been in “auto” mode.

dwall · 07-12-2020, 08:15 AM

Update: I checked everything that was suggested and all checked fine. I noticed my ground wire coming from the battery to the frame looked rusted and loose. I cut the wire and put a new connector on it. Cleaned the frame off and replaced. All is working now. Not sure if this is the whole problem but it’s working now. Going on a week long trip in 2 weeks so I’ll see. Thanks for all the help.

Gord · 07-12-2020, 08:51 AM

Glad to hear you have a resolution. Have a great trip. Safe travels

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