Solar panels

trevskoda

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Looks ok ,batts should be wired pos to pos and neg to neg, but the take of should be pos of the first battery and neg of the second batt for best results.
 

wildebus

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Looks ok ,batts should be wired pos to pos and neg to neg, but the take of should be pos of the first battery and neg of the second batt for best results.
Trev - Hard to tell 100% from the photo, but I think it IS wired that way?
I see it as Bottom battery is providing the +ve, and Top battery providing the -ve.
 

brian c

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You should know David. You taught me.
pos batt1. Neg batt2 Pos batt 2. Neg. batt 1 Think I’ve said that right.
 

brian c

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Ok. Meter on dc. Pointers to red. And black where they join the controller. Reads 13.8./ 13.7alternating
 
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brian c

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Now that’s something I can’t do. Handicapped at fiddly things in awkward. tight places. Sorry. Brian
 

wildebus

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Yes, please.
I may also need you to disconnect one of the wires to get a voltage without a load on the panel.
Assuming you are asking to double-check if the panel is a 12V or 24V panel ....
If it were a "24V" panel, then the voltage at the PV inputs would be around the 30V mark or so, but whatever it is, it would be over the maximum voltage a "12V" panel would read, no?
So even checking with load would still confirm one way or the other?
 

Philip Tomlinson

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Assuming you are asking to double-check if the panel is a 12V or 24V panel ....
If it were a "24V" panel, then the voltage at the PV inputs would be around the 30V mark or so, but whatever it is, it would be over the maximum voltage a "12V" panel would read, no?
So even checking with load would still confirm one way or the other?
Panels range in voltage even those that are around 18v. If three panels are being connected together it is important to know the voltage and amperage to connect them by the most method that will give the highest output.
 

wildebus

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Panels range in voltage even those that are around 18v. If three panels are being connected together it is important to know the voltage and amperage to connect them by the most method that will give the highest output.
indeed so. But there tends to be just the two main variations to need to worry about
 

Chasn

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There is no such thing as too much solar. If your battery isn't big enough to soak up the power running the fridge off the inverter soon uses it up. I often power the fridge off the inverter when stopped during the day. It saves gas, is green and avoids having to turn the gas on and off. Unfortunately my fridge takes 15A otherwise I would leave the inverter on overnight as well when wild camping.
 

mfw

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There is no such thing as too much solar. If your battery isn't big enough to soak up the power running the fridge off the inverter soon uses it up. I often power the fridge off the inverter when stopped during the day. It saves gas, is green and avoids having to turn the gas on and off. Unfortunately my fridge takes 15A otherwise I would leave the inverter on overnight as well when wild camping.
Have to say my old van only had 150w panel and 2 120ah leisure batteries i think they were - i never used hookup even when it was free - refillable gas is not expensive - even used inverter for hoover and never had problem with power - you are correct about green energy but you could say the same about a portable wind turbine which would almost certainly work a lot better in uk winters
 

Robmac

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Have to say my old van only had 150w panel and 2 120ah leisure batteries i think they were - i never used hookup even when it was free - refillable gas is not expensive - even used inverter for hoover and never had problem with power - you are correct about green energy but you could say the same about a portable wind turbine which would almost certainly work a lot better in uk winters
I was always good for 3-4 days without any solar panel running my fridge and lighting off of 2xTrojan 125's. I now have 1x100W solar panel which is rigged to trickle charge the vehicle battery when the hab batteries are full.

We are never in one place for more than a couple of days when wildcamping so running the van will charge the batteries in between. Apart from that we would be on EHU so I see little point in increasing my solar power.
 

trevskoda

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There is no such thing as too much solar. If your battery isn't big enough to soak up the power running the fridge off the inverter soon uses it up. I often power the fridge off the inverter when stopped during the day. It saves gas, is green and avoids having to turn the gas on and off. Unfortunately my fridge takes 15A otherwise I would leave the inverter on overnight as well when wild camping.
My little fridge uses one quarter of an amp through a 600w smart soft start inverter.
inv a.jpg
fridge a.jpg
fridge c.jpg
 

davef

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I have a very simple solar set up on my van and would be interested to hear the opinions of those with more knowledge than me if it is efficient or not. A single panel feeds via controller to the leisure battery which is connected to the starter batteries via a voltage sensitive relay which can operate in both directions ie when either leisure or starter battery reaches the critical voltage the relay trips and connects both together. The tripping voltage seems to be about 13.7v.
 
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