[Triple7]

Hi all,

After picking up the motorhome from storage yesterday we noted that the batteries were not up to their usual standard of charge,(12.4v leisure and 11.5 van) and that the solar panel regulator, an Alden SPS110, had an led light showing "down 20%", which I understand means charging. However, on looking at the Sunware Fox LCD Display it was showing 00.0 amps.

This was confusing considering it was a very bright, hot, blue sky day with plenty of sunshine. So, the 85w solar panel should have been charging quite a respectable current.

On getting home I got the multimeter out and have the following readings which don't make sense:-

Whilst the solar panel was connected to the regulator and the regulator connected to the EBL99 (the load and batteries), I found 12.9 V from the solar panel connector at the regulator and 12.7V from the regulator to the EBL, and these appears sensible to me. Being very careful and with the Silver screen across the solar panel to kill any current, I then disconnected the solar panel. On removing the Silver screen I noted 19.7-20.4V as a raw solar panel voltage. This again looked OK.

I then reconnected the solar panel back to the regulator but this time included the multimeter connected in series through the 10A point on the multimeter. The reading was 0.00 amps???? I removed the multimeter and this time connected it in series from the regulator to the EBL. The reading was 0.01 amps.???

So I think I have confirmed that the solar panel is not charging therefore the question is why?? The regulator appears to be controlling the voltages normally but no current is being seen. Is this likely to be the regulator or the panel thats faulty? Please don't say the 85w panel.

I have checked the panel on the roof and there is no damage and no cracks. All appears normal and the panel is clean. It's mounting bracket is silkaflexed to the roof, so although I can see the wire going into the junction box under the panel, I can't get at it. However, the cable from the panel appears undamaged. This system was working normally when the van went into open air storage 5 weeks ago.

Any ideas please??






Another thing to fix, when does it end. :?: :?

 

[sallytrafic]

Disconnect the panel and short circuit the panel with the 10A range of your multimeter you will then get the Isc reading for the panel and you can compare that with a typical spec for a 85 W panel which will be around 5A in full sun.

I suspect the regulator

 

[Triple7]

Hi Frank,

Thanks for the reply.

I did not know one could just short the panel across the multimeter to read current flow, with no load. I suppose then that the multimeter provides the load.

So I have just disconnected the panel again from the regulator. It read 20.5V in bright sunlight but was reading 00.0amps on the 10A scale. I switched the cables down to the lower reading connection on the multimeter(max 0.2A) and found it reading 0.85 while set to 20m in the amp range. I'm assuming this means 20milliamps and therefore the panel is producing 0.8 milliamps, i.e. 0.008amps.

Oh bugg**. I suppose this means the solar panel has given up the ghost for some unknown reason. :roll: :?

 

[sallytrafic]

Right now we know that the short circuit current is approx zero.

Is it possible to get to the junction box?

This has all the symptoms of a high resistance contact. Your DMM has such a high impedance on its volt ranges that it will effectively ignore a high resistance when measuring open circuit voltages. Its very low impedance on the Amp ranges ensures that if there is a high resistance in the circuit that it measures then all the voltage will be dropped across that high resistance an no or very little current will flow. Your battery is also a low impedance.

So you may be lucky and find that it is a high resistance contact in the junction box or a high resistance blocking diode but unfortunately it can easily be a dry joint within the panel or a cracked piece of silicon.

 

[davesport]

Shorting the solal panel with an ammeter is the easiest & quickest way of checking the panel is producing "power"

If you've determined that the short circuit current is effectively zero then as Frank says you'll have to have a look inside the junction box on the rear of the panel. It's a bit of a mystery as the voltages you're seeing sound the same as I recorded from my panels.

Good luck in your quest. Let us know what you find.

D.

 

[Triple7]

Hi Frank and Davesport,

Sorry for my late reply but have just got back from the New Forest and a red hot south coast beach, so have been without internet.

I will follow your advice and try and get to the black junction box on the underside of the panel. Unfortunately, as the solar panel is fixed to the roof on its Alden supports with sikaflex, I cannot get at it, as the gap around the edge is too small. I will try again tomorrow, but I think I will have to find a way to break the sikaflex bond and remove the panel. :roll:

Interestingly, whilst away I spoke to Eddie from Vanbitz and he suggested checking the connections within the junction box as apparently they can easily become loose if not fitted correctly. His point was that a poor connection would breakdown upon any reasonable draw, but still show a good voltage when not under load.

Thanks again and I will let you know how my investigation goes.








errr,

Any ideas how to break the sikaflex bond??? :? 8)

 

[sallytrafic]

In my perhaps over technical way that is what I was saying and its why without a bit of extra thought voltage on its own can be such a poor diagnostic tool.

As to Sikaflex how many different Sikaflexes are there? I would start with a bit of white spirit having tested it on a hidden piece of your van first. That and a razor sharp knife.

 

[Triple7]

Hi all,

Well no matter what I tried I could not get access to the junction box under the panel so........the solar panel is now off the van. I used a flexible blade with a sharp end and was able to gently work it into the sikaflex joint until it came free.

Here it is:-

and here is inside the junction box on the back of the solar panel:-

I must admit to not exactly understanding what I have found. When I connect directly to the panel terminals in the above picture, it gives out just over 20V in bright sunlight but still only gives 1.5milliamps (1.5 on the 20m scale under amps).
As a double check, I connected a 5w bulb across the terminals and the voltage crashes to 0.1V and the bulb doesn't even glimmer.

So I thought I would check the diode (at least I think its a diode) that can be seen connecting the 2 terminals:-

This is the reading when connected with correct polarity:-

and this is the reading when connected with reverse polarity:-

Now, as far as I can work out the diode is working correctly. It has a resistance when connected reverse polarity (ie it allows some current flow) but does not allow current flow when correctly connected. (the 1 on the meter means infinity resistance)

Am I correct in assuming all this means the panel is fried, :roll: :? only wish I knew what caused it as we are so gentle with this bl**dy van.

 

[Triple7]

As an aside to all the above, whilst following the cable all the way from the solar panel to the regulator, which is under the drivers seat next to the vans control box(EBL99), I found the following whilst checking and stripping all the wiring.

The wires are thick and study and do seem up to the job. The connections in the photograph below look good, completely soldered, and were covered individually with insulation tape. Then covered in more insulation tape. Furthermore, this was surrounded by the plastic cable armour that can be seen top right of the photo and hanging down on the left of the photo. This cable armour has a split down its full length so that the cable can be inserted. This was then further covered again in more insulation tape and then secured with screw clips to the underside of the van floor.

BUT, Why the short extra bit of cable ?????
and why not blue Alden cable all the way to the regulator?????

Furthermore, note when the 2nd piece of Alden cable becomes the other cable, that whoever did this job soldered the red wire to the blue and the black to the brown????? I wondered why at the regulator the black wire was routed to the + terminal. :roll: SO, it was wired correctly but.........

Is it me or does anyone else think this is shoddy workmanship??
You won't be surprised to find who fitted this solar panel...................

Brownhills. :roll:

Anyway, does anyone see a problem if I re-seal this cable back into the cable armour and secure back under the van????
Or, should I replace the red and black wire completely and make a single joint on the first connection on the left????
Is water likely to get into these joints and cause problems????

SO, WHO said this motorhoming lark would be a relaxing hobby. Step forward whilst I get my barrett .50 cal.

Why me. :lol: 8)

However, please don't let this distract from the main solar panel issue in the preceding post. That is the main problem! Thanks.

 

[sallytrafic]

Diagnostics over the internet is always difficult. The diode you can see is a bypass diode (not a blocking diode) and it has no purpose on a single panel installation. It isn't causing the problem as far as I can see. No I'm afraid it does look like the panel has a high resistance contact inside. This might be caused by corrosion rather than by bad handling.

Alden panels have a good reputation have you tried talking to them. I'm not sure but Brownhills may not be a good intermediary.

Before scrapping the panel is there anyone else that can look over it in case we are missing something obvious.


As too the wiring well as you say its shoddy practice and not related to th efault, but more worrying is the length of the cable compared to its thickness. Although difficult to tell from a photo it looks less than 2.5mm² and must be over 5 metre long, perhaps more like 8m.

 

[sallytrafic]

Further to my post above

I have actually repaired a solar panel well I had three and managed to repair one of them but they were BP panels and you could see where the joints were so I carefully drilled holes into the rear and located the faulty joints and then opened up the hole and resoldered and in one out of three I was succesful. Not I think an option for you.

Just to give you confidence that I'm not spinning a yarn and my long distance fault finding isn't misleading I've just googled and found this >here<

 

[davesport]

Hi Triple 7.

I'm in a bit of a rush but here goes. Obviously your panel's faulty 8O so you can go down one of two routes the way I see it. Either buy new or have a closer look at the panel & see if a repair can be effected. Probably not cost effective to have anyone else do this but it may be an interesting project to have a look at yourself. Frank's done this before but for me & probably you it would be the first time. I'd definitely have a closer look & possibly destroy the panel in the process rather than write it off without looking. Nothing to lose etc.

As for the wiring :roll: Well, I could only go as far as describing it as shoddy. The split corrugated sleeving is a legitimate way of protecting wires where you can't thread the tubing over the wires.

The soldered joins :roll: well, I'd personally eliminate as many of them as p[ossible & I'd also have staggered them so there was no possibility of them ever coming into contact.

If you're going as far as replacing the panel. I'd also replace & optimise the wiring. Maximise the cross section of the wiring wherever possible & eliminate as many joins as possible. Cover all the connections in glue coated heatshrink & sleeve everything that's exposed.

Good post so far & an excellent future reference for peeps with similar problems.

Let us know how you proceed. Good luck, D.

 

[Triple7]

Hi Frank and Davesport

Thank you both very much, interesting reading.

Yes, I'm trying to get RoadPro to help with this panel, as they were the Alden importers and reps until not so long ago, ie When the panel was supplied. The panel has a 20 year guarantee so should be an easy issue. However, as always this is complicated as the fitter, Brownhills, are no longer Brownhills (if you know what I mean :roll: ) and the importer is no longer the importer. SO I'm left with a broken expensive panel that everyone says is someone else's problem. I can't afford to just forget it and replace it, I just don't have the £500-600 for a new panel.

I have tried to find a contact for Alden but so far no luck. I just keep finding resellers of Alden equipment. The only website so far that I think is Alden is http://www.alden.fr/index.html , but my french is pretty poor so I'm not sure if this is the right place for solar panels.

I have spoken to Eddie from Vanbitz, the current Alden importer, and although very helpful and would have replaced the panel immediately without question, he did not supply the panel so would be seriously out of pocket to replace and then challenge Alden.

So as you can see, I'm stuck in the middle. I called RoadPro this morning and they have said they are going to call me back, so I'm hoping they will help. I will let you know what happens.

A couple questions please,
1) what the difference between a blocking diode and a bypass diode?

2) and, what exactly is the problem when you say Frank,
"but more worrying is the length of the cable compared to its thickness. Although difficult to tell from a photo it looks less than 2.5mm² and must be over 5 metre long, perhaps more like 8m."
What should the wire be and why?? However, you are right when you say the cable length from the panel to the regulator is about 8m.
The blue Alden cable says "05VV-F 2X4 mm2" on it, but the black cable says nothing but each wire is about the same thickness.

Davesport, I agree about not just throwing the panel, but I don't want to drill any holes in it or pull it apart just yet, as its supposed to have a 20year warranty. Also I agree about all the wiring joints and will replace the black cable with more blue Alden cable connected with a single connection. Whilst appart I will thread some shrink rap and seal each connection.

Thanks and fingers crossed.
777

 

[Kees]

I think there are two solder joints within the junction box that are not visible from the top. These are the ones where the terminal block solders to the printed circuit board. When you screw the terminal screw, it puts a big strain on these joints and it may be that one of the joints has cracked, giving a high resistance joint. Try connecting your ammeter across the two solder pads above the terminal block. If the full power is then produced, it will show that the terminal block needs re-soldering on the rear-side.

Good luck

Kees

 

[sallytrafic]

I think there are two solder joints within the junction box that are not visible from the top. These are the ones where the terminal block solders to the printed circuit board. When you screw the terminal screw, it puts a big strain on these joints and it may be that one of the joints has cracked, giving a high resistance joint. Try connecting your ammeter across the two solder pads above the terminal block. If the full power is then produced, it will show that the terminal block needs re-soldering on the rear-side.

Good luck

Kees

Kees could have a point. Better still though connect your ammeter to the two flat tinny looking strips coming out of the panel.

A bypass diode is in parallel with the panel and prevents broken or shaded panel dragging other panels in an array down. In a single 12V panel application it could if you wished be removed without affecting the circuit.

A blocking diode is in series with the panel and prevents the battery discharging back through the panel. These days they are often omitted completely because the regulator has other components that do the same job or the blocking diode is at the regulator end.

If your cable is 4mm² then it is marginal at 8 metres for voltage drop. I'm not sure what your max short circuit current will be as I don't know the exact size of panel so my calculations have an element of guesswork. Some regulators are cleverer than others in compensating for voltage drop but still losing more than 4% over the run is bad practice

 

[Triple7]

Hi Kees and Frank

Yes tried that. I connected the multimeter directly to the tinny strips coming directly from the panel and before the PCB. Unfortunately, got exactly the same results. Thanks for the further idea though.

I read this as 1.7milliamps connected directly to the tinny strips in bright sunlight. (Ignore the white cable connected to the terminals. Its not connected to anything, I just used it to make some of the testing easier.

Frank
I think I understand what your saying now regarding the cable thickness. If I'm right, your pointing out that 8m of 2.5mm2 cable would cause large resistance losses (and hence a voltage drop), and therefore would be considered poor practice and is inefficient.
8m of 4mm2 cable would have exceptable resistance losses and interestingly is about the limit for 4mm2 cable.

Hopefully once this is sorted, I will replace the black cable with some more blue Alden 4mm2 cable and will create a single connection under the van, as opposed the farce that Brownhills made under the van.

Also, thanks for the explanation regarding the diode's, very interesting.

Mark from RoadPro rang this afternoon and informed me that they do not deal in Alden products anymore but will be asking Alden to call me tomorrow regarding the panel 20 year warranty. Hopefully positive news.
Interestinly, he is going to show them this thread as explanation of the problems. Lets hope Alden join MHF, as it would be excellent to have another manufacturer on board. I hope they see the positive outcomes from being visible on a site such as this.

ATB.777.

 

[Patrick_Phillips]

Only two things I can add to this:
1. Our Alden panel was wired Blue positive, Brown negative. That caused me some problems :evil:
2. Alden´s phone number is 0033388747940. Claire usually answers the phone in French but is actually English. Sabastien Schrick is their techy and speaks pretty good English.
Regards
Patrick

 

[Triple7]

Thank you very much Patrick. Very useful information.

I will give Alden the chance to call me as per Marks instructions from RoadPro before calling them. However, great to have a contact name and number.

All the best,
777.

 

[Kees]

Hi 777

Just a point about multimeters. The 10A range will have its own internal fuse and it is easy to blow this. If you passed 1A or more through the smaller current ranges, then these may have been damaged and will give incorrect readings. You said earlier that you had connected a 5W bulb across the panel as a double check and the volts dived to 0.1V - was this via the terminal block or directly across the foil leadouts from the panel? Sorry to keep on about this, but I've still got my money on a broken joint under the terminal block!

Kees

 

[Kees]

Hi 777

Just a point about multimeters. The 10A range will have its own internal fuse and it is easy to blow this. If you passed 1A or more through the smaller current ranges, then these may have been damaged and will give incorrect readings. You said earlier that you had connected a 5W bulb across the panel as a double check and the volts dived to 0.1V - was this via the terminal block or directly across the foil leadouts from the panel? Sorry to keep on about this, but I've still got my money on a broken joint under the terminal block!

Kees