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

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

The TRM-50 digital overload relay is designed to protect loads from damage caused by high currents while enabling operational control.

• 15-50 A (adjustable overload value)
• 50% fixed current asymmetry
• Adjustable fault delay time
• Adjustable operating mode (automatic, semi-automatic, manual)
• When you purchase a TENSE current relay, you receive a ready-to-use device - current transformers are included.

Device application and operation

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

When the device is turned on:

• The relay energizes, 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.
• After the time expires, the relay trips, the contact switches to terminal 1, and the OUT indicator goes off.

The TRM-50 series electronic current relay is designed to automatically disconnect loads when the maximum allowable currents are exceeded. It features a programmable trip range, trip time, and settings for reversing the trip. There are 3 modes for returning to the "operating state" - MANUAL, SEMI-AUTO, AUTO.

Reset modes

• Manual mode: To reset the device after an overload, press the reset button. The corresponding LED lights up.
• Semi-automatic mode: Allows the device to automatically reset the system three times in case of an overload and then waits for a manual reset on the next fault. The corresponding LED lights up.
• Automatic mode: The device automatically resets the system after each overload error. The corresponding LED lights up.

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

Current asymmetry 50% (fixed)

If the difference between the highest and lowest current in the phases exceeds 50%, the device enters asymmetry error mode within 2 seconds (prevents system damage in case of phase failure).

If an asymmetry error occurs:

• The display group of the two phases that caused the error blinks and the ERR indicator lights up.
• To exit the asymmetry error mode, a manual reset is required.

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: terminal connection
• Contacts: 5 A / 250 V AC (active load)
• Cable diameter: 2.5 mm²
• Weight: max. 250 g
• Mounting: on DIN rail
• Maximum height: <2000 m

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

Basics