Zahra RST-25 Relays & Current Transformer

Features:

• The electronic phase relay RST 25 offers phase, philure shift, phase flashing, asymmetric, Phase sequence and also under and overvoltage control.

• Undervoltage:The desired undervoltage limit can be adjusted down to-25% UN.

• Asymmetry:The adjusting over-and undervoltage limit, the asymmetric limit is slso adjusted.

• Time Delay:The switch off time can be adjusted by the potentiometer “Time Delay” from 0.1……5  seconds. With this function it is possible to adjust the time for the identification of the failure.

• Contactor Control:If a phase fails during operation at load or one of the contacts of the contactor or circuit Breaker is defective,(contact bounce or scorched contacts), RST 25 recognizes the failure, And also the feedback voltage,and switches off depending on the setting of “Time Delay”. The RST 25 controls the phase shift. If there is a phase failure the angle from the feedback Voltage is 30°. The RST 25 recognizes this failure.