Intermittent Electrical Issue

[Sianna]

Post winter problems are non stop this week. I have an intermittent electrical issue where all the power in the MOHO just turns off at random intervals, some times 30 seconds, some times 3 hours but I lose all power and have to press the power back on along with the water pump and lights.

roves to be an issue in the night when the toilet pump is lost as is the fan in the heater - at -3 last week with kids in bad it’s not good.

The only identifying feature is that the power unit Panal has a single light bulb that flashes on once the power cuts off is the 14v bulb for the leisure battery!

has anyone got any advice on this or similar issue?

 

[GeoffnDee]

The Sargent power supply unit (EC450 ?) shuts down if there is to much or to little charge in the batteries , if you are on mains hook up maybe the battery charger (PX300) is faulty and overcharging ? You could try switching off the charger and see if things improve .

 

[Sianna]

Thanks, I have tried that but it still does it, could it be the same from the solar panel over charging?

 

[GeoffnDee]

Yes , there was a post on here recently and it turned out to be a faulty solar controller , The other thing that can cause the solar to over charge is if the connections have been made in the wrong order , the battery must be connected to the controller before the solar panel connection . I thought you had the problem at night ? but you could disconnect the solar and see if it improves (reconnect in the order given, or disconnect solar input to controller only) . Have you a meter to check the actual voltage at the battery. You could try covering the solar panel , if you do not want to touch the wiring , using carpet, cardboard or similar to cut off its input.

 

[TheBig1]

It may depend on the amount of load on the battery/charger. If the leisure battery is reaching the end of life, the voltage can drop off dramatically when the heating suddenly draws extra current for the fan etc. The panel is designed to shut down with low voltage. When the load is off, the battery recovers some voltage allowing the panel to turn back on

Will happen more at night when there is no solar power helping

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[Sianna]

RE-connected in the correct order now and will leave it on overnight and tomorrow to see how we go - fingers crossed

 

[GeoffnDee]

Did you leave the solar disconnected for a while and did it stop overcharging if you did ?

 

[Sianna]

Did you leave the solar disconnected for a while and did it stop overcharging if you did ?

Only left it off for a min then re-connected it as (annoyingly) its been on all evening and not dropped out once so it may because the sun has gone but ill let it ride to tomorrow and see when the sun makes an apperance now its been connected in the correct order - thanks

 

[Sianna]

Yes , there was a post on here recently and it turned out to be a faulty solar controller , The other thing that can cause the solar to over charge is if the connections have been made in the wrong order , the battery must be connected to the controller before the solar panel connection . I thought you had the problem at night ? but you could disconnect the solar and see if it improves (reconnect in the order given, or disconnect solar input to controller only) . Have you a meter to check the actual voltage at the battery. You could try covering the solar panel , if you do not want to touch the wiring , using carpet, cardboard or similar to cut off its input.

Update: I reconnected the system in the (now) correct order and this fixed the issue for about 48 hrs while the system remained on, but today its gone off 3 more times. So I have now disconnected the solar panel and left the system turned on to see what that brings. I’ve checked the leisure battery an it looks brand new and if I think back I think the dealer fitted it when we bought the vehicle last year, so should be OK.


It went back to the dealer last year with this fault and they replaced the solar controller so again hopefully this is OK as well. Is the solar controller adjustable? Can it vary how much power goes in etc?

 

[GeoffnDee]

The controller normally has some adjustment to allow it to be set to the type of batteries fitted as some are charged at different rates , If you do not have this information about your controller if you can say what make and type it is maybe someone will have this information. It may also help to know the type and model of battery fitted to be able to advise on the required setting.
The PSU EC460 (if that is what you have) reads the actual voltage in the batteries, which would be useful to know , press the select button on it to get each battery reading.
If you still have a problem when the solar is disconnected maybe the PSU is faulty, Sargent electrical should be able to advise you about this.

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[Sianna]

The controller normally has some adjustment to allow it to be set to the type of batteries fitted as some are charged at different rates , If you do not have this information about your controller if you can say what make and type it is maybe someone will have this information. It may also help to know the type and model of battery fitted to be able to advise on the required setting.

Contoller is a Duo Battery Charge Controller - I have the manual.

The battery is as per this pic - settings on the controller are: Sealed lead acid battery 1 Gel battery 2 Flooded battery 3, its currently on setting 1

 

[GeoffnDee]

Seems ok , I think you will have to see what happens now the solar is disconnected (I have added to my last post)

 

[pappajohn]

Sianna
Your solar regulator input from panel is back to front.....
Red = +
Black = -

It could have knackered the regulator.

 

[GeoffnDee]

Well spotted pappajohn ,

 

[Sianna]

I was fuming when I saw this! mainly because i had not spotted it and the control box had been re-fitted by the dealer last year to retify this fault - then this moring I went out to check, tok the box off the wall from under the seat and the polairty is correct. the oringinal picture shows the wires from a funny angle and the wires going into the contoller are correct, checked with a meter today as well.

Other pictures show the inputs this morning with the sun out.

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[GeoffnDee]

Glad to hear the wiring is ok, Have you checked the actual voltage at the batteries with your meter , the number one battery looks low on the picture , but that may be increasing ,also what do they read when the Sargent control panel shows 14+ volts. If the controller is working as it should and it is the only source of power into the batteries, perhaps the Sargent PSU is shutting down before it should. Sargent should be able to help with information about this if you let them know the voltage readings you are getting. They are normally very helpful with information regarding their control systems.

 

[Diabalo]

With the sun out and showing 22.1v from the solar panel the batteries should be showing a higher voltage than they do, they should be at least in float mode so about 13.5v with the onboard charger off and the same with it on.

 

[Sianna]

With the sun out and showing 22.1v from the solar panel the batteries should be showing a higher voltage than they do, they should be at least in float mode so about 13.5v with the onboard charger off and the same with it on.

Thanks for all the details and help. Both batteries register 13v at the terminals with the solar panel on and nothing turned on.

I have changed the priority of the solar charge to 90/10 to battery 1/2 to see if this helps and also changed the type of battery to option 3 (flooded battery)

 

[Sianna]

Weekly update (this has been going on for too long now!) I think its a overcharging issue. If I leave on all the internal lights during the day the electric remains on, if I turn off everything then the solar overcharges the batteries and it cuts out.



Im now trying dfferent settings 0-9 in regard to the charging priority to see if this makes any difference.

Dealer who sold the MOHO cannot find the issue and think its “fixed”, once I’ve done the 0-9 settings over the next few days (if its sunny) ill see what the outcome is before I call the local mobile repair guy who will hopefully come up with a plan/solution!

 

[autorouter]

The whole point of a solar controller is that is controls the charge from the solar panels to the batteries, and doesn't overcharge them. If it doesn't do that there's a fault, whatever the settings of the Batt1/Batt2 split. You should see 14.4V, possibly up to 14.8V, in 'absorption mode' ie actively charging. It should then switch to about 13.4 to 13.8V when it goes to 'float mode', ie just keeping the batteries topped up. Any more than 14.8V means there's a fault.

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[Sianna]

The whole point of a solar controller is that is controls the charge from the solar panels to the batteries, and doesn't overcharge them. If it doesn't do that there's a fault, whatever the settings of the Batt1/Batt2 split. You should see 14.4V, possibly up to 14.8V, in 'absorption mode' ie actively charging. It should then switch to about 13.4 to 13.8V when it goes to 'float mode', ie just keeping the batteries topped up. Any more than 14.8V means there's a fault.

Thank you, where am I looking for the 13 & 14 v reading? Battery terminals or power controller or digital display?

 

[autorouter]

Thank you, where am I looking for the 13 & 14 v reading? Battery terminals or power controller or digital display?

At the battery terminals to start with. If OK there you could see if it's OK at the solar controller terminals. There's a theoretical possibility that the Sargent power unit is triggering an overvoltage even though the voltage is normal, so that's something to watch out for. But these intermittent faults are the hardest to trace.

 

[Diabalo]

The easiest thing to do is rule out the solar controller by either disconnecting the panel or covering it over.

 

[Sianna]

New solar controller fitted last week, connected in the right order, been on all week and away this weekend with no issues, hopefully fixed.

in regard to the connection sequence with solar panel last, how do you go about it when you need to disconnect the leisure battery for maintainance or change? Do you want have to disconnect the solar panel for each time?

 

[Itsmcb]

I used to just remove the positive feed from the solar panel where it's connected into the controller. I have recently fitted a switch to isolate when working on the van electrics

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[Sianna]

I used to just remove the positive feed from the solar panel where it's connected into the controller. I have recently fitted a switch to isolate when working on the van electrics

Thanks, what switch did you use a normal domestic or something special?