The POWERSWITCH family comprises DOLD solid-state switching devices for single-, two- and three-phase loads: relays for mounting on a cooling plate or a common heat sink, and contactors with a matched heat sink for DIN rail, ready for use without thermal calculations. DCB technology (Direct Copper Bonding) dissipates the heat from the semiconductor, which allows high continuous currents at a small width. Switching is contactless, wear-free and silent, so the family is intended for circuits with high switching frequencies and for operation at high temperatures.
Versions for resistive loads switch at zero crossing, versions for inductive loads at the voltage peak. Variants with an analogue input control heater power by pulse packets; variants with load monitoring detect undercurrent and overcurrent, i.e. a burnt-out heater or a short circuit, without additional measurement. The PK 9265 contactor with a MOSFET switches DC loads - valves, LEDs, DC heaters - without arcing and contact bounce, which in DC circuits extends the service life compared with an electromechanical relay.
DOLD lists the applications: heating controls, extruders and injection moulding machines, furnaces, pumps, three-phase motors, lighting controls, packaging machines. For railways we propose them for passenger area, point and trackside cabinet heaters and for loads switched many times per hour. Selection requires checking the load current against the derating curve at the cabinet temperature and short-circuit protection with a semiconductor fuse; the datasheets of the individual types state which versions carry UL approval.
Parameters (selected types, from the datasheets):
