TRIGGERING UNIT SKW3 ZC FOR SIX THYRISTORS 3-PHASE STATIC CONTACTOR WITH ZERO CROSSING TRIGGERING • Power supply voltage 230/400 Vac • Line voltage for the thyristors, max. 690Vac • Auxiliary control voltage 12Vcc built-in • Galvanic isolation 4.000V through pulse transformers • Triggering of the whole range of SEMIKRON thyristors • Indicator LEDs, power (green) and trigger (yellow) • Built-in fuse • Trigger control on zero crossing TECHNICAL DATA Power supply voltage Power consumption Control signal Triggering current Operation temperature Humidity Weight AC 230/400 V +10% -20% 50/60 Hz 9VA voltage: DC 8 - 30 V consumption: 2mA at DC 12V 500 mA @ VGT = 5V -10 at 60ºC 10 - 95% w/o dew 420 gr The module is equipped with pulse transformers, and has been designed to trigger 6 thyristors in W3C antiparallel connection. It is useful that the thyristors are equipped with RC circuits. The module is most appropriate for applications as a three-phase static relay for load switching in AC operation. Switching on is performed after the control voltage is applied, waiting when the thyristor current crosses zero. The thyristors are triggered by connecting the J1(+12V) and J2(+trigger), on the one hand, and J3 (-trigger) and J4(ground) terminals, on the other. This can also be accomplished by using an external voltage of 6 to 30 VDC connected between J2(+) and J3(-). To supply other devices (max. 50 mA) the internal auxiliary voltage of 12 VDC(J1: +12V, J4:0V) can be used. By providing a step-down transformer at the power input terminals, the thyristors can be triggered from a line voltage up to 690 VAC, since the pulse transformers whithstand this voltage. In this case, some little changes on the module have to be done (change of the resistors R43, R44, R45). for 330kΩ (or two of 150kΩ) 3W minimum).Those rsistors are calculated to for a W3C connection in series with the phases. In case to connect the antiparallel thyristors in series with the load, and both (thyristors + load) in triangle, resistors have to been changed or they can be damaged. 14/04/00 22 14/04/00 23