Solar Install

rotrax

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I have today ordered two 200W panels, 30A controller and the leads connectors, cable, fuse and gland box to join it together.

The rigid panels, 1m x 1m, will be mounted with the recomended air gap underneath to the rear of the pilothouse roof. They will be wired in parallel.

I inherited our solar array on the previous boat and did not install it.

Can the more knowlegable advise the best location for the 30A fuse? I assume near the battery connection but am not sure.
 

billcole

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I have today ordered two 200W panels, 30A controller and the leads connectors, cable, fuse and gland box to join it together.

The rigid panels, 1m x 1m, will be mounted with the recomended air gap underneath to the rear of the pilothouse roof. They will be wired in parallel.

I inherited our solar array on the previous boat and did not install it.

Can the more knowlegable advise the best location for the 30A fuse? I assume near the battery connection but am not sure.
I would say as near as possible to the battery, the reasoning being that the fuse is to prevent the wiring overheating if there's a fault... the only thing that could supply enough current to overheat the wiring is the battery, so therefore the closer the fuse is to the battery the less unprotected wiring you have
 

jwfrary

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Should be a fuse, generally MCB are considered more convenient, on either side of the controller.

(Makes changing out the controller a lot easier in the future too)
 

Daverw

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I would expect the fuse to be close to the power source, in this case the controller not the battery
 

PaulRainbow

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The fuse is to protect the wiring between the controller and the battery, therefore the fuse belongs as close to the battery as possible.

There is no need to fuse the wiring between the panels and the controller, in this installation, in terms of circuit protection.
 

Daverw

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just a question Paul, I assume that is due to the battery being capable of significantly more than the 30amp the controller can supply?
 

noelex

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As others have said install the fuse close to battery.

Circuit protection on the input (solar panel) side is only needed with with three or more panels and then only in some wiring configurations.

However, the facility to disconnect the solar panel input from the controller is desirable, or even essential in some installations. Many install a switch or circuit breaker on the input side as part of the installation to make this easier but this needs to be in addition to fuse or circuit breaker on the output side.
 

dslittle

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However, the facility to disconnect the solar panel input from the controller is desirable, or even essential in some installations. Many install a switch or circuit breaker on the input side as part of the installation to make this easier but this needs to be in addition to fuse or circuit breaker on the output side.

Exactly what I did so I hope it’s right…
 

PaulRainbow

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just a question Paul, I assume that is due to the battery being capable of significantly more than the 30amp the controller can supply?

Yes Dave, the fuse is there to protect the wiring from the power from the battery, in the event of a short.
 
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