Hank the Tanks Dodgy battery and solar system

merl said:
OK, here's a plan for you Barry.
You buy a new mppt.
We'll temporarily connect both old and new up and swap a panel back and forth and that'll demonstrate the improvement (or not)
We then disconnect the panel and I'll measure the standing current for both, repeat with a connected covered panel (there wont be any but we'll do it anyway) ;)
After data gathering 🤭you decide how to proceed. 100% accurate and better than scouring for internet opinions, it wont take long and it'll put your mind at rest.
Send the mppt back if you dont keep it.
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LOL! No need for that. Ill take your word for it. :D Ill maybe have a chat with you today about the controller though
 
Ok so some progress. Got the dreaded clamp off the battery box. A two man job but my neighbour refused to give up getting the bolts out despite me telling him they were never coming out. So all matter of hammer, drill and power tools were brought out until he finally accepted they werent coming out. So a very sharp Japanese bendy hacksaw was produced and with a bit of effort from both of us we just hacked through the clamp (leaving the sawn off ends still bolted in). It was important to get it as close to the far side as possible in order for the new battery to be able to slide into place and it was a bit tricky. Only slight issue is I nicked the top side of the box slightly and caused a tiny hole. He reckons it wont effect the strength of the box but will epoxy it. There are holes all over it anyway.

So ill order the battery now and get it sent here to at least make sure its going to fit.
 
merl said:
ALL solar controllers consume a standing current, this varies considerably from model to model and is obviously very small compared to the solar gain during normal operation. In the winter over a prolonged period of no/low solar the solar controller can actually consume more power than the system produces and then it's effect will be negative. Very system and condition dependant though.
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Well yes of course there is some draw for any controller. The Victron 165/250/350 /430 stand by draw is 4mA so to all intents and purposes my answer to Barry is correct. The reviews are wrong. Of course if something has gone faulty somewhere that's a different matter.
 

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barryd said:
Ill see if I can find the thread about the Votronic drain. It was likely a faulty unit but I seem to think there was more than one person had the issue. With my old controller on the old van I had it a couple of times over Winter. I heard the Solar alarm going off in the van and when I checked the leisure battery had dropped to 10.5v. In the end what I did was I just pulled the fuse between the battery and the controller and isolated the leisure battery over winter. This cured the issue. With the Cab battery on the old van I just whipped off the negative lead under the bonnet. You can't really do that with a modern van.

With the current controller I have had no issues (so far). It must still use power though as it has two green flashing lights for both batteries which have flashed away all winter showing full. However to be fair there hasn't been a month where its not had a run out really.

This is why I was reluctant to change it as I kind of hate fixing stuff thats not broke but I appreciate its old hat. That said the bloke at off grid solutions "sniffed" at the proven differences between PWM and MPPT.
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If I remember correctly Barry you used the Load output on your controller. The Load output will draw power from your battery if anything connected to it is turned on
 
I wondered how much my controller consumed for itself so looked and:-
Dunno if this is good or bad TBH.


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Nabsim said:
If I remember correctly Barry you used the Load output on your controller. The Load output will draw power from your battery if anything connected to it is turned on
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Yes of course. It was just a handy output to have due to its location in the wardrobe. Easy to wire a 4 bank of sockets to it. It was also useful on that old controller that the LED screen showed you how much power anything connected to the load socket was using. For example I knew my laptop when fully charged but plugged in to the load socket with a 12v adaptor pulled about 12-14w watching a movie but that increased to 16-17 if you plugged in USB speakers. Same roughly for the TV. Michelles laptop though when it went through a 300w inverter (she now has a dedicated 12v adaptor) pulled about 19-22w because of the inverter overhead.

Thats how anal I am about watts and power. :D
 
Pudsey Bear said:
I wondered how much my controller consumed for itself so looked and:-
Dunno if this is good or bad TBH.


View attachment 141160
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Looks like you've got the specs for 2 different controllers there Kev? If it's the LHS then that's very good, middling if it's the RHS. The low power mode looks interesting, maybe explore that further? Maybe you turn the screen off?
The Victrons are brilliant, less than 10mA as Neil has pointed out, I recall seeing one a while ago that was really high, something like 100-200 mA, Renogy I think?
 
merl said:
My experience with the semi flexibles was like many others....ie pretty crap. I think if you pay for a big name brand semi flexible you'll have a better chance of longevity and decent output BUT that's just what I've read.
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The semi flexible panels are misnamed. They are not at all flexible once fitted. Yes, you can curve them a bit to fit onto a non-flat surface, but they need to be mounted so that there is absolutely no flexing afterwards, whether from wind or from solar heating. Stick them down well and they are fine.
There is a different sort, which are like a rubber mat. They stick down well, and can be walked on, which is useful. The trouble is that they use a different panel technology and are only about 8% efficient, rather than the 22% of modern 'normal' panels. So ytou get a lot less power for a given area of panel.
 
barryd said:
It would be a bit tight when you add in the brackets. The same width brackets keep them narrow but they add a fair few cm to the length. I don't want more than one anyway.
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Brackets don't have to make the panel bigger at all. They can be fitted on the inside of the panel.
 
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