Cause of high voltage?

[tkowalyk]

Our refrigerator kept cycling on and off. I then noticed our sun explorer monitor was flashing and registering voltage between 16 - 20 volts. I was plugged into shore power.

I disconnected from shore power -
I disconnected the batteries and connected them one at a time, and still got a high voltage reading.

I disconnected both ground wires - reconnected to shore power only - still high voltage.

I then disconnected the ground wire coming from the solar panels and still getting a high voltage reading.

I was getting normal readings for a while yesterday - I checked all of the fuses on the refrigerator and it came back on for a while.

I am plugged into shore power now without the solar ground wire connected and the current voltage on the sun explorer is 15.8v

I am afraid that the high voltage fried the board on the refrigerator as it now appears dead.

It is a new AS - not our first and in 25 years of RVing I have never experienced a problem like this.

What is the problem?

[DaveFL]

Does the solar panel have a regulator? Most solar panels will produce varying levels of voltage depending on sun input, over voltage also can kill batteries if batteries are fully charged and regulator not stopping input.

[lewster]

I would look to your converter as a potential problem source.

Remove your solar charge controller from the battery charging circuit and teat he output from the converter. If it is over 14.2-14.4VDC, you have a problem with the converter.

If that is not the source of the abnormally high DC voltage, then your solar controller might be the source. Re-connect the controller into your battery charging circuit and disable your converter by flipping the marked breaker in your circuit breaker box.

No check the voltage a your batteries. If your controller is working properly, you should be getting 14.2-14.4 VDC on bulk and absorption phases and 13.2 for float charging. If you are still getting abnormally high voltages, your solar controller has the problem.

I would still suspect the converter though, as most solar charge controllers are not capable of outputting that high a voltage once the efficiencies of the panels and voltage drop are factored into the equation.

Also, don't rely on the voltage you are seeing at the controller, as you might be getting a false reading. Verify that the batteries are showing this high voltage as well when measured at the batteries.

[tkowalyk]

Thanks for all the feedback. The voltage at the batteries looks to be ok with a Voltmeter.

Mysteriously the voltage is back within normal range (at least for now) and the refrigerator is back on.

I have an appointment at the dealer in a few weeks. I will keep you guys posted.

[swampthang7]

Were you camped,or docked at home? The reason I ask is possible transformer failure in neighborhoods can cause MANY fluctuations.

[tkowalyk]

Originally Posted by swampthang7

Were you camped,or docked at home? The reason I ask is possible transformer failure in neighborhoods can cause MANY fluctuations.

In a campground. I have a progressive monitor and the monitor indicates everything is ok.

They checked out the power and everything is ok. Nobody else having any problems either.

[tkowalyk]

Here is an update to our high voltage problem...


We had a storm roll through the other afternoon, and with the cloud cover, the fridge switched itself back on.

It ran all night, and it wasn't until the sun was up that the Sunexplorer monitor once again read high voltage - 16.4 VDC. I was getting high voltage - low amp reading .3 amp. Normal would mid 13 VDC with close to 8 Amos.

To avoid overcharging the AGM batteries, I disconnected both batteries (all ground and negative connections).

The Sunexplorer panel then read 20.2 VDC for a couple of minutes, then went completely dead.

I have been on shore power for the last 24 hours and the fridge hasn't shut down.

I am going out today and get a multimeter. I have a couple, but not with me

Hmmm - comments?

[lewster]

What are the voltage output specifications on the solar panels? You are either getting full open circuit voltage from the panels shorted to the charging circuit of the charge controller, or the controller is shorted and giving you a false reading.

Either way, I think you are looking at a new solar charge controller.

[tkowalyk]

Well - it looks like it is the convertor.


With a new analogue multimeter, I measured about 13VDC on each of the batteries. After connecting the battery cables, without the solar panels connected, the voltage jumped to 16 VDC. I do not get any measurement on the cables when not connected to the battery.

Any recommendations on what brand convertor? I wonder if Airstream will substitute a different convertor than the OEM under warranty - my new AS is 5 months old.

Thanks

[tkowalyk]

I finally got the high voltage problem fixed.

Colonial Airstream had it for a week, and the problem surfaced again.

It was not the converter.

It was the SunExplorer controller. After we knew what the problem was, the repair was done in 15 minutes.

Working with Colonial Airstream was great - they had both the bottom end of the converter and solar control module shipped to them so depending on the diagnosis, the fix could be done quickly.

The problem was hard to find - and it had both airstream and the colonial technicians scratching their heads because the high voltage problem was intermittent and they had diagnose the problem while the voltage was high.

Back on the road again and in Gettysburg for the Bluegrass Festival this weekend.

Awesome!

[tkowalyk]

Originally Posted by DaveFL

Does the solar panel have a regulator? Most solar panels will produce varying levels of voltage depending on sun input, over voltage also can kill batteries if batteries are fully charged and regulator not stopping input.

Dave - you had it nailed!

It was the solar control module. The regulator was allowing high voltage to the batteries and not registering that the batteries were charged.

The batteries are ok - thank goodness I have AGM batteries.