High power PCB relays offer low contact resistance

TTI IP&E – Europe now stocks OMRON's G9KC series of high-power PCB relays. The 480VAC, 40A relay's four-pole structure can replace larger multipole contactors and three or four single-pole relays for three-phase (three-wire or four-wire) power supply models, contributing to a smaller and lighter charging station design while saving labour costs and improving quality.

"Higher charging currents accelerate charging speeds, but the heat generated by the switching devices contributes to an excessive temperature rise within the wallbox," explains Dermot Byrne, director Industry Marketing Transportation, TTI Europe. "The low contact resistance of OMRON's G9KC PCB relays helps prevent parts within the charging station from overheating, which could cause a temporary charging power limitation. This capability creates new potential for EV charger designers to develop systems that charge faster and more efficiently, with greater reliability and predicted lifetime."

The relay features an optimised structure with a mechanically coupled, double-break contact design for demanding AC wallbox and pedestal charger designs. With an initial contact resistance of less than 6mOhm, it is less likely to act as a hotspot, improving charging efficiency and performance. Also, its lower operating temperature minimises the likelihood of the charge cycles reaching charging current throttling thresholds, while also helping to improve the reliability and longevity of the relays and surrounding components.

The G9KC is approved by the UL/C-UL, TUV and CQC safety standard certification authorities and meets the requirements of the IEC 62955 standard for high short-circuit capacity and IEC 61851-1 EV conductive charging systems. Also, the auxiliary contact is compliant with the IEC 60947-4-1 mirror contact requirement.