TENSE phase protection relay – adjustable asymmetry 5–50%

The phase protection relay from TENSE (Turkey) is designed to protect three-phase motors and other three-phase devices from power supply faults. The device monitors correct phase sequence, phase asymmetry, undervoltage, overvoltage, and ensures safe load disconnection when preset limit values are exceeded.

Thanks to a wide range of settings, the relay is suitable for most industrial and commercial applications, especially where precise and stable motor protection is required.

Key features

• Phase sequence control – protection against incorrect connection.

• Adjustable asymmetry: 5% – 50%.

• Adjustable undervoltage: 260–360 V AC.

• Adjustable overvoltage: 400–480 V AC.

• Adjustable error delay time (Err In): 1–30 s.

• Adjustable recovery time (Err OUT): 1–30 s.

• Clear indication on a 3×3 segment display.

• High precision and fast response to network faults.

• Mounting on a standard DIN rail.

Operating principles

Normal operation

If all phase voltages are within limits and the phase sequence is correct:

• relay turns on,

• LED OUT is lit.

High voltage error (H)

• If the phase exceeds the set limit → wait time Err In, H will be displayed.

• The relay turns off, OUT shuts down.

• After a drop of 5 V below the set value, Err OUT starts, relay reactivates.

Low voltage error (L)

• Drop below set limit → waiting for Err In, L will be displayed.

• The relay switches off.

• After voltage increases by 5 V above threshold → waiting for Err OUT, relay activates.

Phase asymmetry (Asy)

• If the voltage difference between phases exceeds the set threshold (5–50 %):

  • After Err In time, ASy will be displayed, relay switches off.

• After asymmetry decreases below (set threshold – 2 %) → waiting for Err OUT, relay activates.

Phase sequence error (pHs)

• In case of incorrect phase sequence, the relay waits for Err In time, then displays pHs.

• The relay switches off and remains off until the correct sequence is restored.

• After correcting the phase sequence, Err OUT will occur and the relay will activate.

Technical data