Solar Panel setup question

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Cruz
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Solar Panel setup question

Post by Cruz »

I've got a leisure battery fitted and it charges using a Merlin 140amp VSR relay.
I now have a 150w solar panel fitted to keep the battery topped up on the two days of summer we get.

Am I right in assuming the VSR will not prevent the solar panel from charging both batteries in parallel (as the increased charge with trigger the relay)? If so how can I ensure all the solar generated power goes to the leisure battery only when camping?

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Oldiebut goodie
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Re: Solar Panel setup question

Post by Oldiebut goodie »

If you have used the relay so that it is actuated by the higher voltage of the starter battery ( normal way) and the solar panel only charges the leisure the relay will not see a higher voltage when the engine is not charging. It will only connect when the engine is running as normal.
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Cruz
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Re: Solar Panel setup question

Post by Cruz »

Just been out and the solar panel is giving out 14.4v

The starter battery is also showing 14.4v and the vsr (Merlin brand) is connected (red led on) as the voltage has gone above the 13.3v disconnect voltsger, thus the solar panel is charging both batteries :-(

Is there a smart car that does not trigger unless the ignition is on?

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Re: Solar Panel setup question

Post by CovKid »

Hopefully I'm reading this question correctly, but normally, the solar controller stops charging when engine is running as technically it sees both batteries as fully charged then. With no engine charge, the solar setup does all the work if it detects a low battery. Or have I missed anything?

The only other thing I can think of is you're trying to charge two batteries from a controller that only handles one battery. I switched to a dual controller and everything works as it should. The relay then doesn't come into it :D
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Re: Solar Panel setup question

Post by Cruz »

It's a single pvm controller.

How I see it is The problem seems to be the nature of the vsr. It senses when the voltage gets over 13.3 volts and then charges the leaisure battery. Once the voltage reaches 12.8 when parked it turns off thus isolating the starter battery from being drained when using lights fridge etc. As the two are in parallel the vsr is sensing the extra voltage from the solar panel and engaging thus charging both starter and leisure battery.

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Re: Solar Panel setup question

Post by Cruz »

Worked it out

I have a dual vsr which sends voltage both ways. I need a single vsr version :ok

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Re: Solar Panel setup question

Post by kentishvanman »

Hi,
My set up if it is of any use is.....Solar panel wired direct to leisure battery via the solar panel indicator box.
Panel then charges leisure battery until it is topped up whether by main system or whatever. Once topped up it stops charging. That's what the instructions say and I have had no problems.
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Re: Solar Panel setup question

Post by bigbadbob76 »

I gave up on my VSR and now use a relay triggered by the D+ terminal of the alternator.
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Re: Solar Panel setup question

Post by CovKid »

There are a few ways to charge both batteries. Initially (before solar) I had a simple relay which charged both batteries when driving. It worked well enough.

Once I fitted solar, I removed the relay and changed the solar controller to a dual-battery one and now the starter battery gets charged as normal when driving. As soon as I switch off, the dual controller is boss and charges both, with the ability to set the percentage each gets. Mine is set to give 75% priority to leisure and 25% to starter.

Put it this way, its sat there for over 6 months and both batteries are always fully charged - even through the Winter. In Summer, they're fully charged by around 8am, regardless of the hammering the leisure might have had the previous evening. I also fitted a changeover switch so if needed, I can also charge a friends battery too during the day. Thats the advantage of fitting 200 watt solar as it allows for redundancy through over-capacity with a reasonable trickle charge in the darker months.

In my experience, if you fit a system that may or should be be sufficient, you'll be disappointed in the longer term. Double what you think is needed and you're completely covered for just about any scenario.

To match the 200 watts, my leisure battery is a huge truck/marine battery similar to one below. Surprisingly they're not much more than many 'leisure' batteries and pack a lot more punch.

Image
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Re: Solar Panel setup question

Post by chewbacca »

I don't know if this idea will help, but put a switch onto your vsr earth wire. If it's sunny, turn off the vsr so the solar charges and maintains your secondary battery. If you need extra charge from the engine at anytime, flick the vsr back on.
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Cruz
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Re: Solar Panel setup question

Post by Cruz »

Thanks for all the replies. I have a single phase vsr on the way. So hopefully that will work. It will be a straight forward swop. If I find that I actually do want the old setup back o can just change the vsr back

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Re: Solar Panel setup question

Post by StoneyT25 »

Can I ask what Dual controller you are using, please? I'm looking for recommendations. Thanks.
CovKid wrote:There are a few ways to charge both batteries. Initially (before solar) I had a simple relay which charged both batteries when driving. It worked well enough.

Once I fitted solar, I removed the relay and changed the solar controller to a dual-battery one and now the starter battery gets charged as normal when driving. As soon as I switch off, the dual controller is boss and charges both, with the ability to set the percentage each gets. Mine is set to give 75% priority to leisure and 25% to starter.

Put it this way, its sat there for over 6 months and both batteries are always fully charged - even through the Winter. In Summer, they're fully charged by around 8am, regardless of the hammering the leisure might have had the previous evening. I also fitted a changeover switch so if needed, I can also charge a friends battery too during the day. Thats the advantage of fitting 200 watt solar as it allows for redundancy through over-capacity with a reasonable trickle charge in the darker months.

In my experience, if you fit a system that may or should be be sufficient, you'll be disappointed in the longer term. Double what you think is needed and you're completely covered for just about any scenario.

To match the 200 watts, my leisure battery is a huge truck/marine battery similar to one below. Surprisingly they're not much more than many 'leisure' batteries and pack a lot more punch.

Image
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Re: Solar Panel setup question

Post by kevtherev »

I use a photonic universe dual battery controller (10A)
It's been working away with a 150w panel for the last four years with no issues.

https://www.photonicuniverse.com/en/cat ... eries.html" onclick="window.open(this.href);return false;
Last edited by kevtherev on 18 May 2018, 06:31, edited 1 time in total.
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chewbacca
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Re: Solar Panel setup question

Post by chewbacca »

https://www.photonicuniverse.com/en/cat ... input.html" onclick="window.open(this.href);return false;

I have this one. Best of both world.

E D I T....

Forgot to say, they do much bigger dual MPPT controllers if you're going nuts on panel size.
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chewbacca
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Re: Solar Panel setup question

Post by chewbacca »

Also, don't waste your money on fancy displays and the like.
You'll be interested in how much current it produces for about a week, then you'll wish you had spent the money on beer.
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