I want to replace the two 100Ah AGM house batteries in my caravan. I can disconnect the CTEK charger from the batteries, but they would still be charged from 3 roof top solar panels via a 30 amp solar charge controller. I want to stop the panels from charging the batteries before I disconnect them for replacing. I have some black plastic which I will tape in place with gaffer tape. However, it seems like I will have to walk on the roof of the van to do this. My query is: can I walk on the roof of my 2009 Crusader Mk2 caravan? . Thank you for your advice, in anticipation. LyntonB
You'll probably receive better replies by posting this again in the "General" forum and with a much more specific subject line.
I strongly suggest you ask the manufacturers or their dealers this question and I really strongly suggest that if you decide to walk on the roof you use lightweight (pine?) load shedding planks.
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I assume your panel array is "extra low voltage" ie. below 120V DC (iirc)? If so you can safely play with its connections at the controller end, just disconnect them one at a time and insulate the one then the other, providing they don't touch all will be good. You can mess with ELV systems with zero personal safety risk.
Edit: I suppose another option is that you could do it at night - seriously :)
-- Edited by Mike Harding on Saturday 7th of January 2023 01:18:47 PM
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Thanks Mike. If possible, I would like to avoid covering the panels. Yes, my panel array is ELV. I cannot disconnect the cables at the controller because the controller is behind a wall panel - only the fascia is displayed on the outside. Maybe I can disconnect the batteries safely if I insulate the terminals of the cables to the batteries to avoid them touching when disconnected. Or maybe I can remove a fuse on the positive cable coming from the controller. I have honestly thought of your suggestion of disconnecting the batteries at night, but can I leave the cables disconnected for a day or so if I insulate the positive and negative cables to prevent them from touching. BTW. I am resorting to consultation via this forum because the company which installed my solar panels has not responded to a couple of approaches I have made. I guess they want the business of replacing the batteries!
-- Edited by LyntonB on Saturday 7th of January 2023 03:34:28 PM
I want to replace the two 100Ah AGM house batteries in my caravan. I can disconnect the CTEK charger from the batteries, but they would still be charged from 3 roof top solar panels via a 30 amp solar charge controller. I want to stop the panels from charging the batteries before I disconnect them for replacing. I have some black plastic which I will tape in place with gaffer tape. However, it seems like I will have to walk on the roof of the van to do this. My query is: can I walk on the roof of my 2009 Crusader Mk2 caravan? . Thank you for your advice, in anticipation. LyntonB
Assuming you have a 12v solar system.
Do you have some blankets you can throw over the panels, maybe using a pole or broom to push them into place if need be, to save having to walk on the roof. ie. something heavy enough to sit on the panels without being taped. I guess you would need a suitable step ladder, or be able to park somewhere next a high bank. Eg a stock loading race or the delivery area of a local supermarket. Even the back of a ute. Still good practice to wrap some insulating tape around each terminal as you remove them though.
Thanks Mike. If possible, I would like to avoid covering the panels. Yes, my panel array is ELV. I cannot disconnect the cables at the controller because the controller is behind a wall panel - only the fascia is displayed on the outside. Maybe I can disconnect the batteries safely if I insulate the terminals of the cables to the batteries to avoid them touching when disconnected. Or maybe I can remove a fuse on the positive cable coming from the controller. I have honestly thought of your suggestion of disconnecting the batteries at night, but can I leave the cables disconnected for a day or so if I insulate the positive and negative cables to prevent them from touching. BTW. I am resorting to consultation via this forum because the company which installed my solar panels has not responded to a couple of approaches I have made. I guess they want the business of replacing the batteries!
So this means when you need to replace the solar controller you throw the caravan away and buy another.
Surely you can get to the wires some how, what happens if you need to reset the controller, my laymans experience you disconnect the wires from the controller and reconnect the wires to do anything with your 12 volt dc electrical.
With our Voltech regulator, to disconnect, remove the earth wire to the battery first, replace last.
If you have an industry standard solar controller, the connectionsare:- left two are solar, middle two are battery, right two are load control.
Just remove the positive on the solar connection first then feel free to go ahead and disconnect power to your battery charger and then remove the batteries last.
Always batteries are the first connection and the last disconnection.
All I do to isolate my panels is get a step ladder to reach the roof of van and then throw some old curtains over the panels. If wind is too strong I place some light timber carefully over the curtains.
Thank you all for your advice. All were carefully considered.
In the end, I covered the roof of my van - and therefore the solar panels - with a canvas tarp over which I pulled a plastic tarp. A check of the controller showed that no power was being produced by the solar panels. Then I was able to disconnect the two house batteries and tape the four lots of cables with gaffer tape to avoid any contacts. The old batteries are now in my garage awaiting disposal.
Again thank you all for your input. I appreciated them all very much.
The original post was 6 months ago, but tips are always useful. I agree with Stretch about isolation switches - I have a switch for turning off the regulator too.
My tips, are:
there is no need to be pedantic about fully covering the panels. It does not take much shade on each panel to reduce the output to very low levels
when reconnecting the system always connect the regulator to the battery first, then connect the solar. This is to avoid damaging the regulator. Some may not be an issue but a sudden spike from connecting that solar while it is disconnected from the battery is a risk. When disconnecting I do solar first, then battery, although there is less risk with that.
I just removed the terminals . Earth first . Then put a leather glove over the active / positive. Being a lineworker its second nature to me . Turned everything off inside . Disconnected solar cables first .
. Thank you for your advice, in anticipation. LyntonB
