SX2DV100
Telemecanique Speed Control Relay

The SX2DV100 relays are used to compare the number of pulses per minute that are being detected to the pulses per minute setting on the relay (using the speed threshold potentiometer and the speed range selector switch). The pulses can be detected from a rotating shaft or from items moving
down a conveyor line. As soon as power is applied to the relay power supply terminals, the timed  contacts and output relay contacts close and the LED indicator comes on.

To allow time for the system to attain the preset speed, a timed contact (internal or external) is used to keep the circuit energized for a preset time period (Ti). If the system is not up to speed by Ti, the relay will shut down the system or motor. If the preset speed is attained by the end of Ti, the output contact will remain closed. If the speed falls below the relay setting at any time after the Ti period is complete, the output contacts open, shutting down the system or motor. The LED indicator is illuminated while the output contact is closed.