Digital overcurrent relay with LED display 3×3 digits TRM-50

Load control/limiting relay, 3-phase, range 15-50 A, manufacturer TENSE (Turkey)

The TRM-50 digital overload relay is designed to protect loads from damage due to high currents while allowing operational monitoring.

• 15-50 A (adjustable overload value)
• 50 percent fixed current asymmetry
• Adjustable fault delay time
• Adjustable operating mode (automatic, semi-automatic, manual)
• When purchasing the TENSE current relay, you receive a device ready for operation - current transformers are included.

Device usage and operating principle

1. Connect the device according to the enclosed wiring diagram.
2. When wiring is complete, connect the power supply. After turning on, the set values will be displayed on the screen for 5 seconds.
3. Use the "A>" controller to set the overload value. The set value is displayed on the left screen.
4. Use the "t" controller to set the delay time. The set value is also displayed on the left screen.

When the device is on:

• The relay turns on, the output contact switches to terminal 3, and the OUT indicator lights up.
• If the current exceeds the set overload value (A>), the device counts down the delay time and the ERR indicator lights up.
• When the time expires, the relay triggers, the contact switches to terminal 1, and the OUT indicator turns off.

The TRM-50 series electronic current relay is designed to automatically disconnect consumers when the maximum allowed currents are exceeded. It has a programmable trigger range, trigger time, and reset settings. Three modes are available to return to "operational" status: MANUAL, SEMI-AUTO, AUTO.

Reset modes

• Manual mode: To reset the device after an overload, press the Reset button. The corresponding indicator LED will light up.
• Semi-automatic mode: The device can automatically reset the system three times in case of overload and will wait for manual reset upon the next fault. The corresponding LED will light up.
• Automatic mode: The device allows automatic system reset on each overload fault. The corresponding LED will light up.

Note: To change the mode, hold the SELECT button for 10 seconds. When the mode changes, the corresponding LED will light up.

Current asymmetry 50% (fixed)

If the difference between the highest and lowest current in the phases exceeds 50%, the device will enter asymmetric fault mode within 2 seconds (prevents system damage when one phase is lost).

When an asymmetry fault occurs:

• The display group of both phases that caused the fault will flash, and the ERR indicator will light up.
• Manual reset is required to exit asymmetric fault mode.

Technical parameters

• Operating voltage: 150-260 VAC
• Operating frequency: 50/60 Hz
• Power consumption: <6 VA
• Operating temperature: -20 °C ... +55 °C
• Display: 3 × 3 digits, 5 LEDs
• Overload value (A>): 15-50 A
• Delay time: 0.1-20 s
• Connection type: clamp connection
• Contacts: 5 A / 250 V AC (active load)
• Cable diameter: 2.5 mm²
• Weight: max 250 g
• Mounting: on DIN rail
• Maximum altitude: <2000 m

Note: TRM-50, TRM-100, TRM-200, and TRM-300 can only be used with current transformers included in the delivery.
TRM-400 can be used with the 400/5 current transformer included with the TRM-400.

Basic