I never got to the bottom of it - spent a month with it over summer and it was on/off working OK/not working.
(following the last reply from Mike at bottom of this post) I removed the panel a week ago and left it simply connected to my old Landy battery for five days or so and it worked faultlessly. I can only surmise that maybe after all the solar/cabling/panel/controller were all A1 and indeed the Cali itself (batteries/wiring loom) was causing an issue??
Regardless - I am told that Victron are certainly the most reliable controllers - certainly the back up has been excellent and they have a five year g'tee. I would not be without the BT/iPhone app set up - it is superb.
Whatever - I'll copy in the conversation flow with the supplier as it might help someone...
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Hi Mike,
Just thought I’d update you following a month with the camper (and solar).
Sadly it did not work properly most of the time and was not putting charge in properly.
Same issue really – see sample pics – this is just one pair of many I took on various days but they all show similar - VW control panel shows actual voltage and amp draw on the system (this I verified many times with a separate volt meter) yet screen shot of Victron app take at same time shows totally inaccurate voltage. In short the controller seems to think it is putting voltage in when it is not.
As before to the very best of my knowledge all wiring is perfect and the panel undamaged and nothing unchanged from 2017 (bar the software updates) with the exact same system when it performed faultlessly.
That (being that you tested the older controller and supplied a new one and both perform the same and were tested fine) leaves the software but Victron say it’s fine!
Max
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Hi Max,
Good to hear from you. The charge controller you returned has been working perfectly on our test rig for the last couple of months so I'm still not convinced it's a software issue - at least not a fault.
The draw (load) current isn't shown on the Victron pic you sent - though it shows the system charging correctly. The charge controller cannot monitor the current draw of your vehicle. Your dedicated VW battery monitor will not show the same charge/discharge current as the Victron charge controller.
Nearly always, where the battery monitor shows a different voltage to the charge controller, there is a weak wiring link somewhere - often a melted fuse holder or a loose/dirty lug connection which increases the resistance and causes a dodgy reading. Another customer had been having a similar issue for a few months and they finally found the problem the other day - a melted contact in the in-line fuse holder was causing intermittent connection which affected the voltage reading.
Whatever the problem is it probably lies with the panel or the wiring of the vehicle. The panel is still generating so it's not a consistent fault. If the contacts inside the panel have come loose/damaged (due to excessive heat or flexing) then there may be an intermittent connection but this would probably require some flexing of the panel to notice, which it shouldn't be able to do. The fact you can re-trigger the controller to start charging by disconnecting/reconnecting from battery and it doesn't automatically keep charging below Float voltage I can't explain.
If you'd like to try a different charge controller, rule out the Victron unit altogether, then we can swap it for an EPsolar Tracer. Bit cheaper as well.
Kind regards,
Mike
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Hi Mike,
I want to keep the Victron option to be honest.
I follow all that – I will pop the panel on a spare battery and see how it works in a very simple set up then.
The load terminals are un used on my set up.
However, I am 99.9% sure all wiring is fine (I am very careful with that sort of thing and nothing is under strain and all connections are very clean and soldered if necessary and all wiring runs are protected and very carefully routed) – I will double check it again though. The VW factory wiring itself is A1 and working fine to the best of my knowledge.
The panel is very securely mounted (Sikaflexed) to aluminium angle each side and this is bolted in four places to the factory rails – all is super solid and flex free.
As I say it was the exact same set up last year that was faultless.
Issue I have pointing the finger at hardware is that if you remember the set up was on my driveway for a week or so when we first noticed this and thus un-moved or subject to any vibration etc and yet the Victron showed not a random pattern as such (as you’d expect with connection/wiring issues) but more the same behaviour each day – OK in the morning and then come afternoon stopping passing current or whatever?
Max
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Hi Max,
Without testing other controllers/panels there's not going to be a way to narrow down where the issue lies I'm afraid. My tests that I do here are usually just a simple panel-controller-battery setup to minimise all variables, so if you're able to do so that'd be really helpful. It might be the panel, I'm just not sure without more testing.
Mike