Solar panel wiring questions

[moss_b]

Hi,

I'm looking to connect a solar panel via a solar regulator to our van. The van is converted and has existing 12v circuits, so I'm looking to connect to these rather than running new wiring to the leisure battery. I've looked how the wires are physically connected and knocked-up a wiring diagram for some of the existing circuits.



From this I'm trying to work out where best to connect the battery and load outputs from the solar regulator. The boxes marked 'A', 'B' and 'C' are where existing connections are available, where I could easily connect to without having to break into any wiring.

I was thinking I could connect the solar regulator outputs as follows:

Battery+ to connections at 'B'
Battery- to 'C'
Load+ to 'A'
Load- to 'C'

Would this work? Should I add any additional in-line fuse between these connections?

Many thanks!

Martin

[Dodgey]

Assuming the relay and switch is an addition of yours for transferring the loads to the regulator (rather than going direct to the LB) then yes, it will work fine. A 3 way switch works just fine without a relay, but it doesn't do any harm . In fact, I can't see what that relay is doing. Just snip the live at A and hook it up to the regulator load.

if you want to monitor the load usage (regulator with a display), make sure you pick an earth point for the load ( - ) on the regulator that is close to the actual earth point of the load appliances or you won't get the load amperage showing on the display.

For fuses - if you add a wire that carries significant current that could be crushed / trapped / cut by accident then yes, add an inline fuse. I put one from the regulator to battery live. Your loads are already fused.

[moss_b]

Hi Dodgey,

Many thanks for getting back to me.

Both the switch and the relay are part of the existing wiring. The switch is essentially the master switch for the existing load; fridge, water pump, lights (which are on the 12v socket circuit) etc. Not sure what function the relay has. I assumed it switches between leisure battery and 12v from the 240v transformer and/or for charging the battery from the transformer. But my electrical knowledge is limited!

If I wire the regulator as per my suggestion I permanently switch on the fridge, lights etc, regardless of the position of the master switch. So it looks like I'm wrong. I've disconnected the regulator again for the time being.

Any other suggestions appreciated.

Cheers

[Dodgey]

Your relay is actually an "extension" of the switch (it's an electronic switch which is triggered by the mechanical switch) - think of them as the same thing. If your drawing is complete, then the switch/relay combo purely switches the 12v output to your fridge etc on or off.

If you still want to retain the functionality of the switch then simply remove the wire at pin 30 on the relay, and plug the regulator load+ into pin 30.

According to your drawing the 12v from the 240v transformer goes straight to the LB - not via any switches or relays.

[windywatson]

Hi,

I have done the same as you and installed a solar panel. As I wanted the panel to provide charge to the 12v LB and hence the 12v system I simply connected the -ve output from the solar regulator to chassis/earth connection C in your diagram & the +ve to the 12v positive connection to my power control unit. This would be connection B on your diagram.

This gives the equivalent of running a cable from the solar panel regulator to your LB which is how it it is shown wired in the solar panel regulator instructions & saves the agro of routing a new cable to the LB.

I have found that this works fine & I've not experianced any problems.


Cheers

[Dodgey]

He's happy with the battery connections, but he's also using the "load" output from the regulator to gain the battery over discharge protection that these regulators provide, but only if you use the load outputs to power all your devices.

[Jaws]

have done the same as you and installed a solar panel. As I wanted the panel to provide charge to the 12v LB and hence the 12v system I simply connected the -ve output from the solar regulator to chassis/earth connection C in your diagram & the +ve to the 12v positive connection to my power control unit. This would be connection B on your diagram.

This gives the equivalent of running a cable from the solar panel regulator to your LB which is how it it is shown wired in the solar panel regulator instructions & saves the agro of routing a new cable to the LB.

I have found that this works fine & I've not experianced any problems.

Ditto; experienced no problems

[moss_b]

Yes, I'm all connected now.

Many thanks to Dodgey for his assistance.