ABB CW Series Instruction Leaflet

ABB CW Series Instruction Leaflet Manual pdf 2 page image

41-241.3L22.3 Indicating Contactor Switch Unit (ICS)The dc indicating contactor switch is a small clappertype device. A magnetic armature, to which leaf-spring mounted contacts are attached, is attracted tothe magnetic core upon energization of the switch.When the switch closes, the moving contacts bridgetwo stationary contact, completing the trip circuit.Also during this operation two fingers on the arma-ture deflect a spring located on the front of theswitch, which allows the operation indicator target todrop. The target is reset from the outside of the caseby a push rod located at the bottom of the cover.The front spring, in addition to holding the target, pro-vides restraint for the armature and thus controls thepickup value of the switch.3.0 CHARACTERISTICSType CW relays are available in the following rangesand taps:Typical 60 hertz Time-Power Curves are shown inFigures 5 and 6. The curves are taken at maximumtorque which occurs with the current leading the volt-age by 30 degrees. (within ±4°) The time curvesapply ±5% at rated voltage.3.1 Trip CircuitThe main contacts will safely close 30 Amperes at250 volts dc and the seal-in contacts of the indicatingcontactor switch will safely carry this current longenough to trip a circuit breaker.( I L VLL )Volts ( 3 single phase watts )Line-toLine Range Taps120 20-120 20- 30- 40- 60- 80- 100- 120100-600 100- 150- 200- 300- 400- 500- 600208 35-200 35- 50- 70- 100- 140- 175- 200175-1000 175- 250- 350- 500- 700- 875- 1000Figure 1. Time-Power Unit. 2. Indicating Contactor Switch (ICS). Note: Phase shifting resistor is mounted in rear.