The reliability of the MC4 connector for PV solar panels by Multi-Contact, has led it to become a de facto industry standard, with over a billion sold worldwide. The rugged connector now has a further advantage as it has been awarded UL approval for operation at 1,500V.
This higher system voltage is a significant advantage for larger arrays, as it means more PV panel modules can be connected in series within a string. The number of strings in an array can therefore be reduced, with a consequent reduction in the number of components required, such as couplings, overcurrent safety switch systems, contact breakers and cables. Combined with the fact that inverters are cheaper in this voltage range, installation costs can be as much as 30% lower.
"The approval process took around six months, and our MC4 connector passed with flying colours without us having to change a single detail," said Selwyn Corns, Managing Director of Multi-Contact UK. "This means existing UL-certified systems can be upgraded to 1500V."
Approvals from other certification organisations such as TUV, CSA and CQC currently remain at 1,000V.
The connectors can be supplied preassembled or they can be attached to cables on site using crimping pliers. Cables up to 10mm2 in cross-section can be accepted, making them suitable for currents as high as 43A.
The MC4's outstanding electrical performance is due to the use of MULTILAM technology, a proprietary contact system from Multi-Contact that uses torsion spring contact elements to produce multiple contact points and ensure high reliability and low contact resistance.