Anyone got any good advice about fitting solar panels

Gareth62

Subscriber
I have just bought 3 x 275w panels. fixing kit and control box and I due to pick up around the 28th June so plan is to fit once we get some nice sun around July time.

Any do's and don'ts
Screw down or bond down or both
Where not to drill on a Mirada I'm planning to run the cable though the roof into the cupboard above the table on the RV's awning side.
 

sundowner

Subscriber
Keep cable runs as short as possible, especially battery to inverter
If you have a rubber roof use lots of sikaflex and screw.
Try to avoid shadows falling on panels------not much you can do about sat dish when it's up, I have a luggage rail around most of our roof so with a low sun it can throw a shadow from any of three directions---- I could have made brackets a little taller to avoid this!!!!
Second what Olly said about cable size--- very important!!
 

adi4

Subscriber
I have just bought 3 x 275w panels. fixing kit and control box and I due to pick up around the 28th June so plan is to fit once we get some nice sun around July time.

Any do's and don'ts
Screw down or bond down or both
Where not to drill on a Mirada I'm planning to run the cable though the roof into the cupboard above the table on the RV's awning side.
Hi there,

I think that you will find that the OC voltage of those panels will be around 36v, which are really designed for a 24v system, ( with a cut off voltage of 28v )
Once the controller has been configured for 12v you can use those panels on it without any problem.

However you will not get as much charge current as you would if you were to install 825w of panels that are designed for a 12v system, ( with a cut off voltage of 13.8v ) they normally have an OC of 22/24V

It is best to screw down and seal/bond with Dicor

We have fitted more than 100 panels over the last couple of years and keep panels, brackets, controllers and cabling on the shelf so If you have any questions feel free to call me on 07831 812120.

Adi & Cassie
 

Ruff Nomads

Subscriber
Decide if you want them to run stuff or just keep the batteries charged.
Ours just keep the batteries charged. ie: the 12v and 240v (via an inverter) run off the batteries to watch telly, run WiFi, use the PC etc, then on a nice sunny day the solars have charged the batteries before we’ve even got going. Simple setup and cost effective. Like Adi says, panels screwed and Dicor.
Wires run off the roof and down through the fridge vent so no extra holes in the roof. I don’t know what the voltage drop is but the solars pump it 40 +V at the controller which pushes about 4.5 amps (on a sunny day) into four 100ah batts. The wires from panel to controller are 6mm dia so maybe could be thicker, if so running them becomes awkward. The cranking battery is topped up via a top up gizmo which nicks power from the leisure when they’re full.
Put the charge controller out of the way and get a remote display.
Note: run all wires in sheath and protect from abrasions. Put a blanket over the panels when messing about with them, they throw out a nasty shock.
 
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car1966

Subscriber
I put dicor under and over the brackets and screw down and run the cable through the air con so i did not drill a hole through the roof and as olley said the thicker the cable the better as you need to get all the charge through
 

Humper

Subscriber
Decide if you want them to run stuff or just keep the batteries charged.
Ours just keep the batteries charged. ie: the 12v and 240v (via an inverter) run off the batteries to watch telly, run WiFi, use the PC etc, then on a nice sunny day the solars have charged the batteries before we’ve even got going. Simple setup and cost effective. Like Adi says, panels screwed and Dicor.
Wires run off the roof and down through the fridge vent so no extra holes in the roof. I don’t know what the voltage drop is but the solars pump it 40 +V at the controller which pushes about 4.5 amps (on a sunny day) into four 100ah batts. The wires from panel to controller are 6mm dia so maybe could be thicker, if so running them becomes awkward. The cranking battery is topped up via a top up gizmo which nicks power from the leisure when they’re full.
Put the charge controller out of the way and get a remote display.
Note: run all wires in sheath and protect from abrasions. Put a blanket over the panels when messing about with them, they throw out a nasty shock.
What is the top up gizmo? My batteries charge great on the solar, but start up battery always going flat but thought the solar would keep that topped up to?
 

Ruff Nomads

Subscriber
Hey Humper.
Your Leisure Batts and Cranking Batt are on different circuits. This is so you can still start the engine even if you’ve left the telly on and run the batteries down. If the opposite happens and your crankier goes flat then you’ll have a switch somewhere that you flick when you turn the ignition key. This temporarily uses the leisure to crank the engine. Your solars will be connected to the leisure batteries so any charge they produce will not get to the engines batt.
Enter the top up Gizmo or Battery Maintainer cleverly takes surplus charge from the leisure’s once the solars have then topped up.
Here is one from Mobile RV although I’d shop around. Any good Motorhome supplier should have one as I would imagine most Euroboxes have the same batt set up.
Hope this helps.

 

adi4

Subscriber
Hey Humper.
Your Leisure Batts and Cranking Batt are on different circuits. This is so you can still start the engine even if you’ve left the telly on and run the batteries down. If the opposite happens and your crankier goes flat then you’ll have a switch somewhere that you flick when you turn the ignition key. This temporarily uses the leisure to crank the engine. Your solars will be connected to the leisure batteries so any charge they produce will not get to the engines batt.
Enter the top up Gizmo or Battery Maintainer cleverly takes surplus charge from the leisure’s once the solars have then topped up.
Here is one from Mobile RV although I’d shop around. Any good Motorhome supplier should have one as I would imagine most Euroboxes have the same batt set up.
Hope this helps.

We keep a 70 amp version of this on the shelf, about £35 (y)
 

Gareth62

Subscriber
Each 275W panel runs at around 36v so wired in series will give me 108v down to the controller which then charges the batteries at around 13v
Shop says use 10mm2 cable form the panels to controller
I was surprised at such high voltage but as the shop said using higher volts and lower amps means thinner cable from the panels to controller ( I think I got it correct but he was getting all technical. My poor one cell brain went in to melt down. )
 
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Gareth62

Subscriber
I also need to do something about the starter battery as at the moment I have a solar panel on the dashboard running in to a cheap controller from amazon plugged in to the cigarette lighter to help keep some charge in the battery
 

Ruff Nomads

Subscriber
I also need to do something about the starter battery as at the moment I have a solar panel on the dashboard running in to a cheap controller from amazon plugged in to the cigarette lighter to help keep some charge in the battery
Gareth. Take a look at the recent post one or two up on this thread regarding the battery maintainer.
 

Ruff Nomads

Subscriber
Each 275W panel runs at around 36v so wired in series will give me 108v down to the controller which then charges the batteries at around 13v
Shop says use 10mm2 cable form the panels to controller
I was surprised at such high voltage but as the shop said using higher volts and lower amps means thinner cable from the panels to controller ( I think I got it correct but he was getting all technical. My poor one cell brain went in to melt down. )
108v?
 

Humper

Subscriber
Hey Humper.
Your Leisure Batts and Cranking Batt are on different circuits. This is so you can still start the engine even if you’ve left the telly on and run the batteries down. If the opposite happens and your crankier goes flat then you’ll have a switch somewhere that you flick when you turn the ignition key. This temporarily uses the leisure to crank the engine. Your solars will be connected to the leisure batteries so any charge they produce will not get to the engines batt.
Enter the top up Gizmo or Battery Maintainer cleverly takes surplus charge from the leisure’s once the solars have then topped up.
Here is one from Mobile RV although I’d shop around. Any good Motorhome supplier should have one as I would imagine most Euroboxes have the same batt set up.
Hope this helps.

Ruff
Yes, I use the switch on the dash to start via the leisure batteries.
Is the part from Adi easy to install.
I will take a couple of pics at weekend of the bits that I believe are part of the solar to get input if it’s already fitted.?
We keep a 70 amp version of this on the shelf, about £35 (y)
adi
Are these simples to install?
Might take some photos of what I have installed over weekend to check if that’s what’s needed.
 

Ruff Nomads

Subscriber
Ruff
Yes, I use the switch on the dash to start via the leisure batteries.
Is the part from Adi easy to install.
I will take a couple of pics at weekend of the bits that I believe are part of the solar to get input if it’s already fitted.?

adi
Are these simples to install?
Might take some photos of what I have installed over weekend to check if that’s what’s needed.
Mine was fitted when we bought the RV but it wouldn’t be a big job. we fitted the Solars and together it all does a great job. Have you tested your engine battery? If the batt is knackered, the maintainer won’t help. Adi would give you more sound advice here.
 

elitegsp

Subscriber
What is the top up gizmo? My batteries charge great on the solar, but start up battery always going flat but thought the solar would keep that topped up to?
driving it should charge the battery up ok, if its not holding the charge i would just replace them & be done with it
 

Humper

Subscriber
Mine was fitted when we bought the RV but it wouldn’t be a big job. we fitted the Solars and together it all does a great job. Have you tested your engine battery? If the batt is knackered, the maintainer won’t help. Adi would give you more sound advice here.
Replaced the battery last year, charges o.k when take out but when I put back in storage and leave for a while looses charge but the leisure batteries stay fully charged all year off the solar.
 

car1966

Subscriber
Replaced the battery last year, charges o.k when take out but when I put back in storage and leave for a while looses charge but the leisure batteries stay fully charged all year off the solar.
Have you got a immobiliser fitted as if i dont use it regularly it will flatten the battery it doesn't use much but that little trickle is
24/7
 

adi4

Subscriber
Ruff
Yes, I use the switch on the dash to start via the leisure batteries.
Is the part from Adi easy to install.
I will take a couple of pics at weekend of the bits that I believe are part of the solar to get input if it’s already fitted.?

adi
Are these simples to install?
Might take some photos of what I have installed over weekend to check if that’s what’s needed.
Really easy to install just 3 wires (y)

Adi
 
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