Series Fuse Rating Solar Panels

Kauaisolarman s hit 190 pvs have an isc rating of 3 75 a and a stated maximum series fuse rating of 15 a.

Series fuse rating solar panels.

8 87a x 2 strings x 1 25 22 18a 15a fail. Mnepv breakers are available in a 6 a rating and that size breaker should not be subject to nuisance tripping. If a module s series fuse rating is 20 amps then you divide that by the combined safety factor of 1 56. When we talk about solar panel ratings we most often talk about wattage.

As i read it a 15 a dc breaker would be safe and the minimum size would be 6 a 3 75 x 1 56 and rounded up. If you want to compare your own solar panels you can find all the different ratings on their specification sheet a k a. Now in the case of 3 panels in series and 4 strings in parallel if one string shorts the max amperage to short is 39 12 which exceeds the 30 amp max current rating of the 10 awg wire. For example if you have four 100w panels connected in series each producing 20 volts and 5 amps the total output would be 80 volts and 5 amps.

If each module s short circuit current is 4 2 amps then you could parallel 3 modules. Commercially made solar panels over 50 watts have 10 gauge wires capable of handling up to 30 amps of current flow. If you connect these panels in series there will be no increase in current flow so fusing is not required for this string. We then take the total amperage and multiply it by a safety factor of 25 5a x 1 25 giving us the fuse rating of 6 25a or 10a if we round up.

If a fault occurs in one string would there be a need for each string in the system to be fused in order to protect the circuit. It has an isc rating of 8 87 amps and a fuse rating of 15 amps. The fuse ampacity rating ifuse should be equal to or less than the cable current rating icable at the maximum ambient temperature. If up to two solar panels or solar strings are connected in parallel and the cable is rated below 1 56 isc a fuse connected in series to the panel must be installed.

Fusing solar panel arrays wired in parallel. This means each seriesneeds a fuse breaker placed in the combiner box as shown here.