WXU-05 Phase Sequence Relay with Over and Under Voltage Supervision
The WXU-05 guards the supply to a motor circuit. It checks that L1, L2 and L3 arrive in the right order and all present, then keeps checking the voltage window while the load runs. The contact it holds goes into the coil circuit of the contactor ahead of the motor, so a wrong supply never reaches the windings.
Sequence First, Voltage Second
Reverse rotation is the expensive failure on a three phase motor: a pump turns backwards, a screw compressor runs dry, a fan blade takes the wrong load. The relay reads the order of the three phases across L1, L2 and L3 and holds the contact out until the order is right. An open phase is called at 70% of the rated voltage, with 165V as the lower limit of that threshold.
One Dial for the Line Voltage
Un is selected in eight steps from 220V to 460V, covering 380V, 400V, 415V, 440V and 460V supplies from the same item. The over-voltage and under-voltage dials then set percentages above and below that value, each from 2% to 20%, with a fixed 2% hysteresis so the contact does not chatter at the threshold. Measurement runs at 45Hz to 65Hz with an error of 1% or less over a range of 176V to 552V.
Delay Against Nuisance Trips
Tt holds the action back for 0.1 to 10 seconds. That is the setting that keeps a compressor online when a neighbouring motor starts and pulls the supply down for a moment. Power on delay is 0.5 seconds, reset time is 1 second, and the knob setting is accurate to 10%.
Contact, Terminals and Panel Fit
The output is a changeover contact on 11, 12 and 14 rated 10A thermal current and 250V 2.5A under AC-15, with a 500mW minimum switching power for low level circuits. Insulation voltage is 500V and impulse withstand 2.5kV. One 18mm module clips to a 35mm rail, with a supply lamp and a red output lamp on the face, and the body carries CE and CCC marking. Send the motor rating, the supply and the quantity to WTAIELE for a quote.
