When setting the relay characteristic/torque angle for the three phase directional overcurrent element, a positive angle setting was specified. This was due to the fact that we consider as polarising voltage, the phase voltage value in quadrature of the current under fault conditions. With directional earth fault protection, the residual current under fault conditions lies at an angle lagging the polarising residual earth fault voltage.
The unit includes a mechanical stop to prevent adjustment below 35°F (2°C). Do not
attempt to set below 35°F (2°C), or the device may be damaged.
1. If the ambient temperature at the thermal element is within the 35 to 55°F (2 to 13°C) setpoint range, turn the adjustment screw located in the top of the case until the setpoint
exceeds the ambient temperature. Confirm that the snap acting switch has operated.
2. Turn the setpoint adjustment screw until the indicating pointer is at the desired setpoint
temperature.
3. On the TC-5241 model, push the manual reset button to put the thermostat into service.
Manual Operation
of Switch
T
C A U T I O N
• When the sensed temperature is below setpoint, the switch is open (terminals 2–3 on
TC-52x1 and terminals L–T on TC-5232), and the tab at the end of the bellows lever is
down. The switch can be momentarily closed by lifting the tab with a screwdriver. See Figure-5.
• Do not attempt to manually operate the thermostat in any other way as this can damage
equipment and void the warranty.
CALIBRATION
All thermostats are precision calibrated at the factory.
REPAIR
This thermostat is not field repairable. Replace the device if necessary.
Bellows
Lever Tab
Figure-5 Manual Operation of Switch on TC-5231 and TC-5241.
