MC4H Solar Fuse Connector for 10x38mm PV Fuses
The MC4H puts the string fuse inside the connector line. One half carries the fuse chamber, the other closes on it, and the pair mates with the MC4 connectors already on the cable. Where a combiner box is not wanted, this is how a string still gets a fuse in series.
A Fuse Where the Two Strings Meet
When two strings are paralleled, a fault in one pulls current from the other through the module cable. A fuse in series with each string clears that reverse current before the cable overheats. Fitting it in the connector line puts the protection at the point where the strings join, which is where the current divides.
Match the Fuse to the String
The body takes a 10x38mm cylindrical PV fuse, the same size as the WTDS-32 DC fuse on this site. Fuse current follows the string rating, so a 30A build wired with 2.5 to 6mm² cable runs to 1000V DC and a 45A build on 4 to 6mm² runs to 1500V DC. Fit a fuse rated for DC and for the string voltage, because a DC arc has no zero crossing to put it out.
Contact, Gland and Sealing
Contacts are tin plated copper at 1mΩ contact resistance, crimped to a cable of 2.5 to 6mm² with an outer diameter of 4.5 to 8.5mm. The gland seals on the jacket and the mated pair reaches IP67, while the open side stays IP2X finger safe. The body is PPO with a UL94-V0 flame class, rated -40°C to +125°C and tested at 6000V for one minute.
When It Beats a Combiner Box
A single string pair on a small array, a telecom site or a short rooftop run does not justify a combiner with DIN carriers. The MC4H keeps the fuse in the cable run and leaves the enclosure out of the bill of materials. Send the string voltage, string current and quantity to WTAIELE for a quote.
