Applications Requiring Turns

There are some applications that require more than one wiring turn through the TeSys Tera controller:

• All NEMA Size 4 applications require one pass through the 3 amp Tera Sensor Module from the external current transformer (CT) secondary. CTs are rated 300:5.

• All NEMA Size 5 applications require two passes through the 25 amp Tera Sensor Module from the external current transformer (CT) secondary. CTs are rated 300:5.

  • MCC units requiring secondary passes using an external CT are factory supplied pre-looped with #14 wire and interposing terminal blocks.

• Certain two-speed constant or variable torque applications require two passes through the TeSys Tera conductor (CT) windows through which the motor leads must pass before being connected to the load terminals on the contactor (T1, T2, and T3). Two passes of the load leads through each window effectively increase (by a multiple of two) the current that the TeSys Tera senses. Verify that the low speed and high speed Full Load Amperages fall within Tera current sensing range.

• All three conductor windows must have the same number of passes, looped in the same direction, for the TeSys Tera to operate properly.

• Passes should begin from the load side of the TeSys Tera through the CT window. The final pass terminates on the load side of the contactor.