Question for the solar panel experts.

Obanboy666

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Sat here bored so decided I would investigate fitting a second solar panel to complement the existing 120 watt factory fitted panel.
spoke to Pilote who said the solar panel controller built into the electrobloc would be ok so started to measure up etc intending to order a 100 watt panel Etc.
The existing panel cable is 2.5 mm twin feeding into a single gland entry box which then drops into a void above the door and is wired into a junction box which has free terminals to accommodate an extra pair of cables from an additional panel.
The easiest way would be to break into the cable on the roof then use 2 to 1 mc4 connectors to connect the new panel. The problem I have is after reading up the 2.5 mm cable would be to small to take the the amps of 220 watts of panel, the cable from the junction box to the electrobloc is 4mm which I reckon would be ok.
What I may do is just fit a 2 entry gland box in front of the existing gland box keeping things separate to the existing panel. What do the experts think ?
25BD5F25-5652-45C9-9AB9-5BA86E651AFA.jpeg
 
Wish I could help I'm sure wildbus will be along and give you the info you need
 
I put another 110 panel on the roof and changed the gland to a double and upgraded to a victron mppt as i was told the pilot one would not cope. Rewired and used mc connectors with y fitting.
 
Sat here bored so decided I would investigate fitting a second solar panel to complement the existing 120 watt factory fitted panel.
spoke to Pilote who said the solar panel controller built into the electrobloc would be ok so started to measure up etc intending to order a 100 watt panel Etc.
The existing panel cable is 2.5 mm twin feeding into a single gland entry box which then drops into a void above the door and is wired into a junction box which has free terminals to accommodate an extra pair of cables from an additional panel.
The easiest way would be to break into the cable on the roof then use 2 to 1 mc4 connectors to connect the new panel. The problem I have is after reading up the 2.5 mm cable would be to small to take the the amps of 220 watts of panel, the cable from the junction box to the electrobloc is 4mm which I reckon would be ok.
What I may do is just fit a 2 entry gland box in front of the existing gland box keeping things separate to the existing panel. What do the experts think ?
OK, quick recap of situation....
The solar controller you are connecting it to ... what are the specifications?
i.e. What is the maximum Wattage it allows? What is the maximum Current it allows? What is the maximum Input Voltage it allows? Is it an MPPT or a PWM Controller?

Using that info allows you to use the following info best:
Let's look at the controller side first.
If the Controller can handle around 240W of PV Power, then you are ok to add a panel (you have had confirmation it is ok for that, I understand from the post), but that is just 1 of the 4 key things you need to know. i.e. Max Wattage, Max Voltage, Max Current, PWM or MPPT.

A "12V" Solar Panel has an input voltage of upto 23V typically (yup, a LOT more than 12V)
If you connect up a pair of 12V Panels in SERIES, you double the Voltage, but the current stays the same. So if your Controller is ok at an input voltage of at least 50V, then a series connection is fine.
If you connect up a pair of 12V Panels in PARALLEL, you double the Current, but the voltage stays the same. So if your controller can handle around 20A, than a series connection is fine.
If the controller can handle BOTH 50V and 20A, then you have a free choice of either SERIES or PARALLEL.

MPPT or PWM Controller?
If it is PWM, then there is no point in a SERIES connection - the extra voltage gets thrown away and you are no better off. PARALLEL is the only way to go.
If it is MPPT, then either SERIES or PARALLEL is ok (bearing in mind Voltage/Current limits discussed above). Series will give marginally less losses in cables and maybe start to work earlier and stop later but the difference is in truth minimal. Parallel gives better protection against shade. a shaded panel in parallel hurts just that panel; a shaded panel in series hurts the entire array of panels.

I am discussing the above before answering your actual question as if the points above are not considered carefully, three things can happen ...
1) You will get extra power from the extra panel. Happy days :)
However, what could also happen is -
2) you could add a panel and it will make no difference whatsoever to your solar harvesting; or
3) you could kill the controller (this happened to a forum member using another make of controller where the supplier gave him one bit of info but did not provide enough detail on another. £300+ worth of kit blown).

Now your actual question ... "The problem I have is after reading up the 2.5 mm cable would be to small to take the the amps of 220 watts of panel, the cable from the junction box to the electrobloc is 4mm which I reckon would be ok".
2.5mm cable is fine for 220W of PV panel, whether you connect in series (voltage double) OR in parallel - so doubling the current. I would not worry about that in the slightest.
 
OK, quick recap of situation....
The solar controller you are connecting it to ... what are the specifications?
i.e. What is the maximum Wattage it allows? What is the maximum Current it allows? What is the maximum Input Voltage it allows? Is it an MPPT or a PWM Controller?

Using that info allows you to use the following info best:
Let's look at the controller side first.
If the Controller can handle around 240W of PV Power, then you are ok to add a panel (you have had confirmation it is ok for that, I understand from the post), but that is just 1 of the 4 key things you need to know. i.e. Max Wattage, Max Voltage, Max Current, PWM or MPPT.

A "12V" Solar Panel has an input voltage of upto 23V typically (yup, a LOT more than 12V)
If you connect up a pair of 12V Panels in SERIES, you double the Voltage, but the current stays the same. So if your Controller is ok at an input voltage of at least 50V, then a series connection is fine.
If you connect up a pair of 12V Panels in PARALLEL, you double the Current, but the voltage stays the same. So if your controller can handle around 20A, than a series connection is fine.
If the controller can handle BOTH 50V and 20A, then you have a free choice of either SERIES or PARALLEL.

MPPT or PWM Controller?
If it is PWM, then there is no point in a SERIES connection - the extra voltage gets thrown away and you are no better off. PARALLEL is the only way to go.
If it is MPPT, then either SERIES or PARALLEL is ok (bearing in mind Voltage/Current limits discussed above). Series will give marginally less losses in cables and maybe start to work earlier and stop later but the difference is in truth minimal. Parallel gives better protection against shade. a shaded panel in parallel hurts just that panel; a shaded panel in series hurts the entire array of panels.

I am discussing the above before answering your actual question as if the points above are not considered carefully, three things can happen ...
1) You will get extra power from the extra panel. Happy days :)
However, what could also happen is -
2) you could add a panel and it will make no difference whatsoever to your solar harvesting; or
3) you could kill the controller (this happened to a forum member using another make of controller where the supplier gave him one bit of info but did not provide enough detail on another. £300+ worth of kit blown).

Now your actual question ... "The problem I have is after reading up the 2.5 mm cable would be to small to take the the amps of 220 watts of panel, the cable from the junction box to the electrobloc is 4mm which I reckon would be ok".
2.5mm cable is fine for 220W of PV panel, whether you connect in series (voltage double) OR in parallel - so doubling the current. I would not worry about that in the slightest.
Many thanks for the reply.
Unfortunately difficult to answer most of your questions regarding the actual solar controller that’s built into the controller, I contacted Pilote who assured me it would take an additional 120 panel plus this diagram - 5B3FDEBE-9952-4E13-9ADD-E241FB40E0F2.png
Unfortunately due to the virus Pilote are now closed for the foreseeable future so unable to contact them.
i have ordered a 100 watt panel and will just connect it as per the diagram. If things go t-ts up at least I have the message from Pilote as evidence they assured me it was ok to add the extra panel. The connection block is located behind a panel above the door and the cable going from it to the electroblok / solar controller is 4mm so that should be ok.
 
Post up (or PM if you prefer) any info written on the controller, or take photos of any labels and post them. Maybe from that can work out or find the extra details.
Seriously, just knowing it can work with upto 220W is not enough to ensure you won't damage anything even if keeping at or below that total.
That diagram would kind of imply you parallel-connect the panels, but still can't be sure. Each input may have its own 120W limit (I had a B2B/MPPT combo like that - it had two inputs for solar and/or wind, each one limited to 100W)
 
Post up (or PM if you prefer) any info written on the controller, or take photos of any labels and post them. Maybe from that can work out or find the extra details.
Seriously, just knowing it can work with upto 220W is not enough to ensure you won't damage anything even if keeping at or below that total.
That diagram would kind of imply you parallel-connect the panels, but still can't be sure. Each input may have its own 120W limit (I had a B2B/MPPT combo like that - it had two inputs for solar and/or wind, each one limited to 100W)
Will have a look tomoss, many thanks.
 
If it came from the factory fitted or was fitted by a competent Dealer it should be a Schaudt Solar Controller. The factory would only fit the parts that went with the Schaudt Unit in the MH. The Pilote we had had a Schaudt Unit and SMC fitted a cheap solar controller that melted when we got some French sun on the panel. As we were visiting the factory we asked if they could help. Their guy looked at the wiring and emailed SMC and told them to do it properly. When we got back to the Uk SMC fitted the correct Schaudt Solar Controller and everything worked fine. Apart from the Electric Bed but that's another story.

Schaudt Solar Controller.
 
If it came from the factory fitted or was fitted by a competent Dealer it should be a Schaudt Solar Controller. The factory would only fit the parts that went with the Schaudt Unit in the MH. The Pilote we had had a Schaudt Unit and SMC fitted a cheap solar controller that melted when we got some French sun on the panel. As we were visiting the factory we asked if they could help. Their guy looked at the wiring and emailed SMC and told them to do it properly. When we got back to the Uk SMC fitted the correct Schaudt Solar Controller and everything worked fine. Apart from the Electric Bed but that's another story.

Schaudt Solar Controller.
It’s actually a scheiber electrobloc, a French company. Managed to find some info online which gave no details of the actual built in solar controller and the factory is shut for the foreseeable future due to the virus so unable to contact them.
I did some investigation today regarding the cable runs as it requires an extra pair of cables for an additional panel into the electrobloc and it would be a nightmare. I have decided not to use the electrobloc solar controller and will be fitting a Victron unit utilising the existing pair of cables and terminating them before they enter the electrobloc and connecting them to the Victron unit. this will be a far easier job and I will have a superior solar controller into the bargain.
 
Wonder why they changed, probably cheaper, just keeping everything French or they fell out with the Germans again.

Our Laika has a separate controller with two battery outputs. These go straight to the batteries ( Habitation and Starter ) works very well and totally separate from the Laika electrics.
 

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