Replacing a solar panel, correct procedure.

n8ess

n8ess

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I’m looking to replace my existing 100w solar panel with a 200w, l have upgraded the controller to a Victron 100-20.

Is it simply unplugging the connectors from the old panel and reconnecting them to the new one. Or do l need to disconnect the battery/controller as well? I don’t have an isolation switch between panel and the controller.

Thanks
 
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Unplugging one panel and plugging in another panel via connections should be fine but if you can put an isolation switch between panel and controller that's best practice,if you have to do any work in the future.
The battery connection to controller should always be connected before solar panels are connected ,this stops the possibility of the solar charger being damaged.
Hope this helps.

Cheers Cris 🍻.
 
Thanks, can anyone attach a link for an appropriate isolator switch, what size would I require?
 
Barriesimpson said:
I can switch off the solar panel charging using the app (Victron) why would you need an isolator switch?
Click to expand...
Victron claim switching off charging in the app is for maintenance only.
I assume the concern is that if you had a problem with the app you might not be able to turn charging back on.
Fogstar give similar advice regarding their battery app.
 
Barriesimpson said:
I have no idea, but on changing my AGM batteries for a lithium one I switched of the charging, did the change and then switched on the charging. Everything is working - so no damage done.
Click to expand...
It's just good practice to have a switch, in case there's a short circuit in your panel, it would protect the solar regulator.
Even if you would need to work on the panel would be easier with a circuit breaker. Although I haven't installed one in mine, is on my to do list 😬
 
Barriesimpson said:
I can switch off the solar panel charging using the app (Victron) why would you need an isolator switch?
Click to expand...
Lots of different ways to achieve a similar result.

I've got proper DC MCBs as fuses which double up as isolator switches in case I want to work on any part of the system.

If I happen to smell cables getting really hot then I can just go flip a switch rather than look for my phone, unlock it, open the app....
 
fishplug said:
Lots of different ways to achieve a similar result.

I've got proper DC MCBs as fuses which double up as isolator switches in case I want to work on any part of the system.

If I happen to smell cables getting really hot then I can just go flip a switch rather than look for my phone, unlock it, open the app....
Click to expand...
Fair comment, albeit a little paranoid maybe?
 
Barriesimpson said:
I have no idea, but on changing my AGM batteries for a lithium one I switched of the charging, did the change and then switched on the charging. Everything is working - so no damage done.
Click to expand...
Do you notice a difference between your task and that if the OP?
Your task of changing batteries is downstream from solar charger. The OPs task of changing panels is upstream.
 
Barriesimpson said:
Fair comment, albeit a little paranoid maybe?
Click to expand...

Paranoid might be a little bit strong :D - but, yes, I'm fairly safety conscious in the van.

Seeing as everything needed fusing anyway then a 'fuse' that can trip and be reset seemed preferable to one that blows and you don't have a spare for while in the middle of nowhere seemed like a good choice.

The fact that it can also be used as an isolator switch (thus negating the need to buy separate isolator switches or go messing around in apps) was a bonus rather than a primary reason for choosing them.

I'd definitely always have an isolator on the battery myself though.

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Barriesimpson said:
I have no idea, but on changing my AGM batteries for a lithium one I switched of the charging, did the change and then switched on the charging. Everything is working - so no damage done.
Click to expand...
Barriesimpson
So if something goes wrong with either the controller or the panel/panels you have no way of stopping the power from connecting with the battery, that is why it is always advised to fit an isolation switch various ones available from plenty of suppliers.
 
headlight said:
In an emergency, if you don't have an isolator switch, you can pull the fuse from the MPPT.
Click to expand...
I could on the Votronic controllers, but I can't on the Victron ones, and I don't recall seeing an isolator swith for either solar bank. :(

Jock.

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Here you can clearly see see yellow fuse on the left of the image.
 
If you have a low voltage from your panels, usual with motorhome stuff, isolating is less critical but a good idea.
If you have a number of panels in series voltages can get pretty high so isolation becomes essential.
 

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