disconnecting leisure battery with solar panel - is it safe?

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Hi all,
first night away at Stratford on Saturday & the leisure battery was completely flat when we came back from watching 'Peter Kay' so we had to start the engine just to get a light on!!
We have a solar panel & that was working fine a few weeks ago but now I'm getting 14+ volts in the morning but down to 10v by the evening with nothing switched on (that I can find).
I want to disconnect the leisure battery and charge & test it but will the solar panel be OK or do I have to turn something off first - obviously I won't let the terminal touch anything!

cheers
Chris
 
They are both connected to the battery terminals. I was just going to disconnect the negative??
I went out just and the voltage has dropped from 13.5 30 mins ago to 10.9 now it's going dark - looks like it must be the battery :cautious:
 

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There is obviously a split charging system as well - I'm not sure how that connects up with it all..

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Sorry to hear of your problems but it sounds like the leisure battery is goosed. :( But checking it first as you plan is very wise!

The advice given above (which is of course right :)) might need some explanation. Many solar controllers work on both 12v and 24v systems and the controller decides which voltage is needed by being connected to the battery first. If you connect the solar first the controller doesn't know if it is expected to output 12v or 24v.

Victron controllers are the exception as they remember the voltage after the first connection but unless you know you have a Victron stick with connecting the battery first. :)
 
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Disconnect the solar panel positive wire at the controller/regulator.
Then disconnect the battery.
Reconnect battery then reinstall Pos wire at the controller.
You mean this wire on the controller?
 

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It isn't only solar. It is best practice to disconnect any source of charging supply before disconnecting the battery connection to the van. Switching off the mains charger and, as stated above, disconnecting the solar panel is normally enough to achieve this.
 
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I've disconnected the positive feed from the solar panel and took the negative terminal off the battery and it's not looking good 8.5 volts :crying:
Now its on a charger for 30 mins or so & I'll see if the voltage drops like a brick when I take it off charge.

The question now is GEL battery or not?

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I've disconnected the positive feed from the solar panel and took the negative terminal off the battery and it's not looking good 8.5 volts :crying:
Now its on a charger for 30 mins or so & I'll see if the voltage drops like a brick when I take it off charge.

The question now is GEL battery or not?
Pointless attempting too charge it. Others who have bought leisure batteries more recently may advise on type.
 
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Get a better solar charger so you can at least see what's going in


See what's in your battery


And buy two of these


I got a discount of 5% on solar charger and battery sensor

And free vent kit for the batteries
 
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Should have given me a shout I was at Stratford all 7 days.
The solar regulator in your photo could be what has cooked your battery. I helped two people out at the New Forest meet both problems with that regulator. One was drawing 1 amp from the battery when there was no sun the other one was putting out a too higher voltage.
That regulator is best avoided like the plague.
 
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Thanks everyone - great help as usual (y) :thanks3:
I'll have a shop around in the morning locally - we're off to Whitstable on Monday so could do with one for then!

cheers
Chris
 
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Should have given me a shout I was at Stratford all 7 days.
The solar regulator in your photo could be what has cooked your battery. I helped two people out at the New Forest meet both problems with that regulator. One was drawing 1 amp from the battery when there was no sun the other one was putting out a too higher voltage.
That regulator is best avoided like the plague.
It was our first time to a Club meet & we should have been there all week and were hoping to meet a few of you, however, my son got Covid (he's fine now thank god) and we had to isolate & so we didn't get there till Saturday and were keeping a safe distance from everyone just in case!!
I was wondering if the solar panels might have cooked the battery - with the amount of sun we had the week before!
How can I check the regulator?
 
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How can I check the regulator?
With it in circuit the input voltage from the panel should be around 17 to 22v and the output when charging should gradually rise to 14.4v and when charged drop to 13.8v.
 
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Sounds to me the Battery is dead and you have been measuring the soler input to the battery ergo no sun = very low volts.

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With it in circuit the input voltage from the panel should be around 17 to 22v and the output when charging should gradually rise to 14.4v and when charged drop to 13.8v.
I'll measure it tomorrow 👍
 
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Sounds to me the Battery is dead and you have been measuring the soler input to the battery ergo no sun = very low volts.
That's what I'm thinking, it's just strange that last time we went away a few weeks ago it was all working fine - we watched TV & used lights etc all night for 2 days with no problem, and the weather wasn't that sunny!
 
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OK it's definitely had it, from charged it drops to 10v without any load - also I can hear it bubbling when it's on charge so a cell must be gone.
Any opinions on which battery is best from these two:
Yuasa L36-AGM class A 95AH Absorbent Glass Mat 'dry' battery I think at £155
or
Halfords HLB750 class B 110AH lead acid battery at £125

Apparently the Absorbent Glass Mat batteries generally last longer but are sensitive to overcharging & high voltage.
 
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OK it's definitely had it, from charged it drops to 10v without any load - also I can hear it bubbling when it's on charge so a cell must be gone.
Any opinions on which battery is best from these two:
Yuasa L36-AGM class A 95AH Absorbent Glass Mat 'dry' battery I think at £155
or
Halfords HLB750 class B 110AH lead acid battery at £125

Apparently the Absorbent Glass Mat batteries generally last longer but are sensitive to overcharging & high voltage.

How much room do you have? If buying a lead acid, I go for 629 flooded truck batteries, preferably non maintanance free versions, so you can charge faster and replace any lost water. These are usually around the 170-180Ah mark for the same prices you're looking at and built like a brick outhouse (but are heavier and larger than your suggestions which might be an issue for you).

This sort of thing:

If you're planning to off grid a lot, start planning for lithium batteries.

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How much room do you have? If buying a lead acid, I go for 629 flooded truck batteries, preferably non maintanance free versions, so you can charge faster and replace any lost water. These are usually around the 170-180Ah mark for the same prices you're looking at and built like a brick outhouse (but are heavier and larger than your suggestions which might be an issue for you).

This sort of thing:

If you're planning to off grid a lot, start planning for lithium batteries.
No I haven't the room for a bigger battery & I don't think we'll be off grid that much, we seemed to cope with the solar panel - but haven't done much more than a couple of days off grid so far.
 
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No I haven't the room for a bigger battery & I don't think we'll be off grid that much, we seemed to cope with the solar panel - but haven't done much more than a couple of days off grid so far.

Even so, I'd measure the space and buy the biggest flooded non-maintenance free battery you can find. It will be cheaper and last longer. Maintenance free just means you can't maintain it, not that it doesn't need maintenance. My last 629 has now lasted 11 years. It has survived 2 motorhomes and a caravan. I've now got Lithium, so for the last two weeks it was relegated to running some massive marquee lights and leader's phone charging for a 2 week scout camp. No sign of it tiring. Yes, you need to top the water up once a year, but that's better than not being able to top the water up and chucking it after 4 years when it runs out.
 
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Halfords HLB750 class B 110AH lead acid battery at £125

someone said on here the halford battery is a yuasa rebranded ?

Yes a rebranded yuasa but in a 100ah efb ie lead acid
Another alternative with the same dimensions and "completely maintenance free" technology, is the VARTA 90A LFD from Tayna Batteries.

I just bought 4 x for £86.08p each, including VAT and next day delivery. They came via Palletways.

Good luck TheLifeofBrian. (y)

Jock. :)
 
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Get a better solar charger so you can at least see what's going in


See what's in your battery


And buy two of these


I got a discount of 5% on solar charger and battery sensor

And free vent kit for the batteries
Is the Victron a simple swap in for the old Duo controller?
 
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