Solar panels not working during the day?

My mistake.. they are in parallel not series...
One of the reasons I am using 2 mppt boxes is that the 70 solar panel goes through one and the 2 x 35 watt panels go through the other.
As they are semi flexible they are stuck to the coach roof making no real ventilation under them but even so, just after they go off in the mornings I have flt them and they are quiet cool.
Also they did come on in the heat of day when the generator (portable) was switches on.

You are now saying one 70 watt panel and two 35 watt panels. Initially you said double that. Viz a 140w panel and two 70w panels

That fits the theory that you are overloading the regulators. When the generator is on the solar regulators will be trying to pass less power.

70 and 2 x 35 should be OK and it not working during the day a mystery. 140 and 2x70 will overload the controllers and could be the explanation for the set up not working.
 
Just an update. I still have exactly the same problems. I have spoken to the original sellers who were not too helpful and suggest that something is coming apart when they get hot and closing when they cool which does not help.
They suggest I contact the manufacturers (gb -sol) which I have done but it is a bit like pulling teeth from a shark. They cannot offer advice but as a goodwill gesture will offer me replacements at cost!
I dont see why I should have to buy replacements after two and a half years use but I don't think I have any other options.
 
Just an update. I still have exactly the same problems. I have spoken to the original sellers who were not too helpful and suggest that something is coming apart when they get hot and closing when they cool which does not help.
They suggest I contact the manufacturers (gb -sol) which I have done but it is a bit like pulling teeth from a shark. They cannot offer advice but as a goodwill gesture will offer me replacements at cost!
I dont see why I should have to buy replacements after two and a half years use but I don't think I have any other options.

What investigations have you made in the past 2 weeks or so to establish the location of the problem.

Have you tried bypassing the controllers to determine if they are faulty or not.

Have you tried connecting one panel at a time direct to the battery to determine which, if any, of the solar panels are faulty.

Can you confirm the size of the panels ( 140 + 2 x 70 or 70 + 2x 35 ) does not overload the controllers. There seemed to be doubt about their size earlier in the thread.

Since you have contacted the panel manufacturer can we assume that you have infact investigated and determined that the panels are defective . If so it is curious that all three exhibit the same fault. It would be curious if both controllers exhibited the same fault for that matter.
 
What investigations have you made in the past 2 weeks or so to establish the location of the problem.

Have you tried bypassing the controllers to determine if they are faulty or not.

Have you tried connecting one panel at a time direct to the battery to determine which, if any, of the solar panels are faulty.

Can you confirm the size of the panels ( 140 + 2 x 70 or 70 + 2x 35 ) does not overload the controllers. There seemed to be doubt about their size earlier in the thread.

Since you have contacted the panel manufacturer can we assume that you have infact investigated and determined that the panels are defective . If so it is curious that all three exhibit the same fault. It would be curious if both controllers exhibited the same fault for that matter.

Vic,
I have taken readings when they are both on in the early morning and there is a current coming from the panels. When they go off I have taken readings with them connected and not connected to the mppt boxes. The boxes are working correctly but the panels are not. All three panels supply power for about two hours after it gets light and tend to stop just after the sun is directly on them
In the evening the 70w panel does not work but the 2 35 watt panels do for about an hour before it gets dark.
The panels are 2 x35 and 1 x70
I have sent half hourly readings to the company who sold me the panels and mppt boxes and the panel manufacturers. One could offer no explanation apart from possible faulty panels and the other suggested I take them off the adhesive on the saloon roof and sent them from Sicily to them for evaluation at my cost even though the 1 year guarantee has expired.
I am not of a mind to throw more money on the same solar panels even at cost
 
that looks as if the panels are thermally incompetent. I agree; don't go for the same make unless, if the supplier is going to hand you some free ones in replacement, you then flog them quickly to a cruiser going in the opposite direction, and buy some reliable ones.

These problems take up so much time and hassle, sadly, when you could be doing other useful things.
 
You appear to have satisfied yourself that the panels are faulty.

In the circumstances the only course of action seems to be to replace them with panels from a different source.
 
I wonder if it worth one last test ?

Perhaps cover the panels first thing in the morning with a light proof blanket. Wait till the hot part of the day, then uncover them. If the fault is due to heat in the circuitry, then they will charge for a while, and then stop when the temp reaches the critical level.

I guess that the internal panel temp when the sun is on them will be a lot higher than the ambient air temp.
 
I wonder if it worth one last test ?

Perhaps cover the panels first thing in the morning with a light proof blanket. Wait till the hot part of the day, then uncover them. If the fault is due to heat in the circuitry, then they will charge for a while, and then stop when the temp reaches the critical level.

I guess that the internal panel temp when the sun is on them will be a lot higher than the ambient air temp.

Light proof and heat reflecting perhaps
 
If as indicated in post #30 they are glued to the saloon roof " take them off the adhesive on the saloon roof "

I would do that and put spacers under the panels to allow more air circulation and check then again.
 
As all three panels appear to have developed the same fault I wonder if OP has bent them too much when they were glued down?
Either that or the panels may have been wired up incorrectly and, in reality, one faulty panel is bringing the others down. It is certainly odd that the same fault appears in all three panels.
 
Last edited:
Just an update.
I took numerous measurements from when they are on in the morning. They do not come on at all during the day and only the smaller panels work last thing at night suggesting a overheating problem.
There are blisters on the panels which tends to back this up.
I did cover them during the day but no change.
I sent all the measurements I had taken to the manufactures who refused on numerous times I asked to comment and said they offer no technical help. It took 2 emails for every time I asked as they would not respond to the first.
They did say there are some failures but only a very small ammount.
There at cost price means that plus vat plus delivery which means I will nearly be paying the same again for them and they will take 4 to 6 weeks to manufacture.
The company is without doubt the worst I have dealt with and for the price I would be paying for a new set from them I would worry they would fail again with no back up.
All I can do is buy new panels elsewhere.
So.. For two and a half years or mabey less I had the most expensive electricity in the world
Thanks for all your help but basically I am stuffed.
 
Top