solar controller apparently not working

[Harrytherid]

I have a (supposedly) 80 watt solar panel flat on the roof where it has been for the past, maybe, 12 years where it has apparently been working fine, though I have not looked at the lights for a good while. After my “woe is me“ session it was disconnected while I did the other work on the electrics which are now complete. We are going off for a couple of weeks so I thought to reconnect it and check it was going. There are no lights on the MPPT controller working . There is not, and never has been, a “load” connected, just the battery from which all the loads are taken. The panel is putting out 18.5 volts at the moment. The controller is delivering 0.5 volts. The controller is a Jutta 10 which I imagine means 10 amps. What might be wrong, please?

 

[wildebus]

if the battery connection is showing 0.5V on the controller, then it would look like there is an open circuit between controller and battery. check connections, blown fuse, tripped breaker, etc.

 

[colinm]

Did you un connect and then connect in right order?
First connect the battery then connect the panel.

 

[Harrytherid]

Ah, thanks for the wonderfully prompt replies chaps. The controller tells me nothing. it has no screen so I used my multi-meter to determine these voltages I mentioned. The last set of connections were done according to that protocol but earlier ones may not have been so could the controller have been damaged? If so I need new controller. I can not remember whether or not I was aware of the connection order. I have checked for continuity between the controller and the battery and there is. First connect the battery then connect the panel? my control panel is connected to the battery, not to the MPPT controller, maybe I have it all wrong.

 

[wildebus]

Ah, thanks for the wonderfully prompt replies chaps. The controller tells me nothing. it has no screen so I used my multi-meter to determine these voltages I mentioned. The last set of connections were done according to that protocol but earlier ones may not have been so could the controller have been damaged? If so I need new controller. I can not remember whether or not I was aware of the connection order. I have checked for continuity between the controller and the battery and there is. First connect the battery then connect the panel? my control panel is connected to the battery, not to the MPPT controller, maybe I have it all wrong.

so, I meant the voltage on the battery connections on the controller.
Assuming you have a good connection to the battery, the voltage at that point should be the same as the battery minus a little bit of voltage drop, irrespective of if the controller is working or not, so I am suspecting a fault away from the solar controller itself.

 

[trevskoda]

Sounds like its bu--ered, splash out on a new votronic, buy a bigger one as you may want to add more panels at some time.

 

[Harrytherid]

Right , first thing I shall do when I get back from my bike ride tomorrow morning will be to string a pair direct from the controller to the battery so I can see it is all OK. then we shall see what is wrong, I hope. I shall report back when I have some news. Thanks again chaps

 

[colinm]

Right , first thing I shall do when I get back from my bike ride tomorrow morning will be to string a pair direct from the controller to the battery so I can see it is all OK. then we shall see what is wrong, I hope. I shall report back when I have some news. Thanks again chaps

From your earlier post i'm uncertain you understood, forgive me if I'm repeating info you already know.
First disconnect cables from solar panel to controller, then disconnect cables from controller to battery.
Reconnect cables to battery, then reconnect cables to panel.
If it's just the controller being 'confused' this will reset it.

 

[Harrytherid]

No I did not get that Colin so thanks for the clarification though when I said the earlier problems I was having are now fixed, my wife this morning in bed said "oh the basin lights did not come on" Why did you not tell me yesterday, women!!. Now I shall first have to sort that out before worrying about the solar panel etc. The whole bedroom end has gone off though the shower is still on so must be with the kitchen lights to which it is next. Presumably when fixing the flush I disrupted the lights, I hope I can quickly sort it. What I struggled with was the TO THE PANEL which I thought meant to the control panel and which I would call FROM the panel. I think I have got it now thanks, Harry

 

[Harrytherid]

whoopee. After sorting our the bedroom lights to the delight of Mrs H, I went on to do the incredibly difficult (in the cramped space of the wardrobe) job of re connecting (to the directions kindly supplied by yourselves) that pesky controller and at least some of its lights are on. I was too tired to squeeze back in to check which lights but tomorrow I will get it the properly wired up and report back. thanks again, Harry

 

[molly 2]

Buy a cheapo controller from e Bay if it works buy a quality one keep cheap for a spare .

 

[Harrytherid]

Working properly at last. I wont bother you with the silly thing I had done but I found the fault and corrected it. So very happy and thanks yet again to all those who helped, even molly 2. Compared to some of the prices I have seen lately my Jutta 10 was not exactly expensive but seems to have been doing the job and now it is correctly wired will, hopefully, do so for ever more. Might get a bigger panel, though, before the winter and I suspect that will entail a larger controller. Although the advice I have encountered recently seems to be for an Ecoworthy set, maybe 120watt. Any comments? Actually 12 volts times ten amps is 120 watts unless either my electrical knowledge or my arithmetic is letting me down, Harry

 

[trevskoda]

Truth is 200w of panels is about the lowest to go for, and use a mppt regulator.

 

[Harrytherid]

Thanks Trevskoda but I am not sure I can fit 200W panel into the area available and yes I would be sure to use an MPPT controller. However panels seem to be smaller for the wattage than mine nowadays so maybe I can fit a 200watt panel which I would do if possible, though I must watch the cost as both me and the Motorhome have a limited life span - 80 and 15 so far, respectively and I am starting to struggle with arthritis. Harry

 

[trevskoda]

Thanks Trevskoda but I am not sure I can fit 200W panel into the area available and yes I would be sure to use an MPPT controller. However panels seem to be smaller for the wattage than mine nowadays so maybe I can fit a 200watt panel which I would do if possible, though I must watch the cost as both me and the Motorhome have a limited life span - 80 and 15 so far, respectively and I am starting to struggle with arthritis. Harry

Yes old Arther creeps up on us all, look for two smaller panels of 100w and link them up.

 

[wildebus]

Thanks Trevskoda but I am not sure I can fit 200W panel into the area available and yes I would be sure to use an MPPT controller. However panels seem to be smaller for the wattage than mine nowadays so maybe I can fit a 200watt panel which I would do if possible, though I must watch the cost as both me and the Motorhome have a limited life span - 80 and 15 so far, respectively and I am starting to struggle with arthritis. Harry

If your existing panel is relatively old (at least in PV panel terms), then you may well find you can get newer ones that are bigger in wattage for the same footprint.
Depending on how you want to do these things, if the existing panel is still ok, and you will only get a small gain by removing it and fitting a larger one, consider getting a portable solar kit - you could use this in conjunction with the existing installation and give you the flexibility of having it tilted and pointed to the sun, therby making it more efficient again compared to flat on the roof.

 

[Harrytherid]

Thanks for the replies lads, I shall think about it and do some research but not until I return from the next trip starting Thursday, Harry

 

[Harrytherid]

Well safely back from that trip and nothing went wrong. Thanks to the advice obtained here, the solar panel/battery setup worked fine. Heating was definitely needed as both Leicester and North Kent were quite cold and did not need to run the engine parked once. Hardly moved in 5 days but both wife and I had colds, caught there as daughter's partner and both sons had streamers when we got there so we needed that warmth. Might be different when weather frosty, though. Does anyone know how to persuade a woman to allow a thermostat to do its job, come on girls, tell me, and why is it that in summer 68 of is too hot but in winter too cold, I don't get it.