On about my electrics again.

Harrytherid

Harrytherid

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I had an auto electrician look at my system the other day,. Charged me £213 for what he purported to be 1.5 hours work which so far as I can see was very little but pronounced all OK except solar panel not charging. Looked at it myself and my multi-meter gave me 8.5volts (no sun at that point) from the charger (Juta 10 MPPT). I tried reading the manual but it has been translate from the Chinese or whatever by a non native English speaker and is incomprehensible to me. The charge light (red) is flickering which seems to be saying that the battery is fully charged. Any comments? please. Battery low light is off and load light is steady on and green. Will 8.5 volts help charge the battery if it does get low or do I need new solar panel?
 
Harrytherid said:
I had an auto electrician look at my system the other day,. Charged me £213 for what he purported to be 1.5 hours work which so far as I can see was very little but pronounced all OK except solar panel not charging. Looked at it myself and my multi-meter gave me 8.5volts (no sun at that point) from the charger (Juta 10 MPPT). I tried reading the manual but it has been translate from the Chinese or whatever by a non native English speaker and is incomprehensible to me. The charge light (red) is flickering which seems to be saying that the battery is fully charged. Any comments? please. Battery low light is off and load light is steady on and green. Will 8.5 volts help charge the battery if it does get low or do I need new solar panel?
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any comments? even if he did a full1.5 hours of work, £213?? I definately used to charge way too little :(

8.5V will do nothing in terms of charging. When there is daylight, the typical "12V" solar panel will output around 20V if not connected and between 16V-20V in operation (numbers are approximate).
This is typical of what you might see on a meter with the panel connected and disconnected (I can fake a disconnected panel with a Victron controller by turning off the charger)
Disconnected (so no charging)

PV - Charger OFF by David, on Flickr

And connected (and charging)

PV - Charger ON by David, on Flickr

There is an interesting video from Victron explaining why when the voltage is too low from the PV Panel, you will not only not be charging the battery, but actually using the battery power to run the controller - so instead of the PV helping the battery, it is draining it! On the Victron controllers, they don't even turn on until the PV voltage is >5V MORE than the Battery voltage.
Have a watch of this ... it is not just relevant to Victron kit.

If it were me, I would be making breaks in the circuitry and checking voltages with my meter to see what the voltages are at various points and noting them down. Once you have the info, be easier to try to make sense of what is happening.
If you ARE getting 8.5V from a disconnected solar panel, it is knackered (or maybe very dirty?)
 
Oh sorry about that, it was 2.5 hours, slip of the pen (finger). Wrong again, Harry! 18v from panel and 8.5 volts from controller. Sounds like controller kaput eh?
 
Harrytherid said:
Oh sorry about that, it was 2.5 hours, slip of the pen (finger). Wrong again, Harry!
Click to expand...

Harrytherid said:
18v from panel and 8.5 volts from controller. Sounds like controller kaput eh?
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the voltage from the controller should equal the voltage of the battery. Disconnect the Battery +ve and check the voltage on the removed cable from the terminal and the -ve on the battery controller connection and see what that reads.
The controller could be pulling it down but you might have a poor connection somewhere along the line (could be on +ve OR -ve line)
 
Sorry but you lost me somewhere along the line there though I think that is what I did. I have printed that out and will go out and check it against the wagon, see if I can make sense of it. Snag is I am not at my brightest at this time of day. Might be best if I look again in the morning.
 
I went out there yesterday, to do the tests you, wildebus, suggested and asked for Julie's help to hold the meter up whereupon she said that as it was her birthday (which I had not forgotten) I should quit messing about with the motorhome and take her over to Newquay to see grandchildren, so being the man of the house and in charge, I did what I was told immediately. Went out this morning to do those checks and found that no lights were on on the controller so I am assuming it is Kaput so looking for a replacement. Preferably at a good price, Any ideas? Panel, no sun, 18.9V so that seems to be OK, yes?
 
Harrytherid said:
I went out there yesterday, to do the tests you, wildebus, suggested and asked for Julie's help to hold the meter up whereupon she said that as it was her birthday (which I had not forgotten) I should quit messing about with the motorhome and take her over to Newquay to see grandchildren, so being the man of the house and in charge, I did what I was told immediately. Went out this morning to do those checks and found that no lights were on on the controller so I am assuming it is Kaput so looking for a replacement. Preferably at a good price, Any ideas? Panel, no sun, 18.9V so that seems to be OK, yes?
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well .... From your description of the original controller, I would quite surprised if it really was an MPPT controller (loads of cheap no-name brands say "MPPT" but they lie).
MPPT is around 30% better than PWM (basic) controllers. But they are usually a fair bit more expensive. I personally stick with Victron as they almost always work fine and if they fail, you get a new one under warranty while under 5 years old.
For your install, a Victron 75/10 or 75/15 would do the job. Pay a bit extra for the SmartSolar version instead of BlueSolar and you can talk to it with your phone to check the operation (for me, the SmartSolar is a feature worth paying for. Cne-off extra cost of around £30 but you can benefit from it for years). Maybe looking at around £80 or so?

If you want cheap e.g. PWM, then just get the cheapest. If you want to send me a tenner, I will send you a brand new PWM Solar Controller. But be warned, it is one of the most popular and common ones for sale, but it is also pretty rubbish as it is PWM.
 
Yes thanks Wildebus. What you say seems to be the case so I have found this: https://www.amazon.co.uk/MPPT-controller-Victron-Energy-75/dp/B075NTT8GH/ref=sr_1_1_sspa?373945598045&hvadid=74148572400055&hvbmt=bp&hvdev=c&hvlocphy=131613&hvnetw=s&hvqmt=p&hvtargid=kwd-74148510177424:loc-188&hydadcr=13540_1856053&keywords=victron+75+15&qid=1687080863&sr=8-1-spons&sp_csd=d2lkZ2V0TmFtZT1zcF9hdGY&psc=1

Is this what you are suggesting I should get? if so I shall do so forthwith. No mention of the 18.9 volts I am getting but looks, to me, like the panel is working well. Sorry about the long address.
 
Harrytherid said:
Yes thanks Wildebus. What you say seems to be the case so I have found this: https://www.amazon.co.uk/MPPT-controller-Victron-Energy-75/dp/B075NTT8GH/ref=sr_1_1_sspa?373945598045&hvadid=74148572400055&hvbmt=bp&hvdev=c&hvlocphy=131613&hvnetw=s&hvqmt=p&hvtargid=kwd-74148510177424:loc-188&hydadcr=13540_1856053&keywords=victron+75+15&qid=1687080863&sr=8-1-spons&sp_csd=d2lkZ2V0TmFtZT1zcF9hdGY&psc=1

Is this what you are suggesting I should get? if so I shall do so forthwith. No mention of the 18.9 volts I am getting but looks, to me, like the panel is working well. Sorry about the long address.
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That does look like the one to me, the only thing I would add is buy one that can handle more solar than you have just incase you want to add more solar. A few quid more now is better than having to buy another one if you do upgrade :unsure:

Regards,
Del
 
Harrytherid said:
Yes thanks Wildebus. What you say seems to be the case so I have found this: https://www.amazon.co.uk/MPPT-controller-Victron-Energy-75/dp/B075NTT8GH/ref=sr_1_1_sspa?373945598045&hvadid=74148572400055&hvbmt=bp&hvdev=c&hvlocphy=131613&hvnetw=s&hvqmt=p&hvtargid=kwd-74148510177424:loc-188&hydadcr=13540_1856053&keywords=victron+75+15&qid=1687080863&sr=8-1-spons&sp_csd=d2lkZ2V0TmFtZT1zcF9hdGY&psc=1

Is this what you are suggesting I should get? if so I shall do so forthwith. No mention of the 18.9 volts I am getting but looks, to me, like the panel is working well. Sorry about the long address.
Click to expand...
that will do the job :)
As been mentioned also, if you are planning on getting more panels, go larger. a Victron 75/15 will handle upto 220W and will only be a little more expensive, if at all.
makes sense to go bigger to start with rather than replace. But within reason ... I have the Victron 100/20 controllers which gives me very little leeway for more panels - but my roof leaves no room for more panels anyway ;)

18.9V is a decent PV voltage so your panel seems fine.
 
Thanks Wildebus and the rest of you for confirmation, I went for the 75/15 for just a fiver more. Maybe my solar input will be more significant now. I can hardly wait. What does the bluetooth do?
 
Harrytherid said:
Thanks Wildebus and the rest of you for confirmation, I went for the 75/15 for just a fiver more. Maybe my solar input will be more significant now. I can hardly wait. What does the bluetooth do?
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allows you to configure the controller (remember to remove the little jumper on the 4 pin white connector when you get it).
allows you to see what you are harvesting, the voltages of the panel and the battery (you can put your meter away!). if you look at my earlier screenshot, that is what you can see with your new one.

when installing, remember to connect battery first, then panel. And make a note of the position of +ve and -ve ... the Victrons tend to be reversed on one side compared to most controllers (it goes +ve,-ve,-ve,+ve instead of +ve,-ve,+ve,-ve)
 
Hi Wildebus again, Got it already. Removed the jumper, good job you said as I would not have known and instructions fairly obscure. Your other instructions are very helpful too. What is white socket for, what goes in it? Will fit tomorrow, got clear day to do that. I wonder why they keep the two negs together.

Regards, Harry
 
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