Direct digital overcurrent relay with 3×3-digit LED display TRM-25

Direct Digital Overload Relay with 3×3-digit LED display, 3-phase with timer, range 0.1-25 A, manufactured by TENSE (Turkey)

Digital thermal relays are designed to prevent and control damage to loads caused by high current.

- 0.1-25 A (adjustable overcurrent value)
- 50% fixed current asymmetry
- Adjustable fault delay time
- Operating mode: adjustable (automatic, semi-automatic, manual)
- Internal current transformer

Device application and operating principle

Connect the device according to the wiring diagram. Once the connection is complete, connect the device to the power. After power-on, the configured values will be displayed on the screen for 5 seconds.

- Use the "A>" regulator to set the overcurrent value. The set value will be displayed on the left screen.
- Use the "t" regulator to set the delay time. The set value will also be displayed on the left screen.

When the device is energized, the relay turns on, the output contact switches to terminal 3 and the OUT indicator lights up. If the current exceeds the set overcurrent value (A>), the device starts counting the delay time and the ERR indicator lights up. After the time has elapsed, the relay switches off, the contact switches to terminal 1 and the OUT indicator goes out.

The TRM-12 series electronic current relay is designed for automatic equipment shutdown when the maximum allowed current is exceeded, with programmable settings for trigger area, trigger time and return time.
There are also 3 return-to-"operating state" modes - MANUAL, SEMI-AUTOMATIC, AUTOMATIC.

Return Modes:

- Manual Mode: After an overcurrent fault, the device must be reset by pressing the Reset button. In this mode, the corresponding LED is lit.
- Semi-Automatic Mode: The device automatically resets the system three times if an overcurrent fault occurs, and then waits for a manual reset if another fault occurs. In this mode, the corresponding LED blinks.
- Automatic Mode: The device automatically resets the system each time an overcurrent fault occurs. In this mode, the corresponding LED blinks.

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

Asymmetry 50% (fixed)

If the difference between the highest and lowest phase current exceeds 50%, the device enters asymmetry fault mode within 2 seconds.
(During motor operation, this prevents damage to the system in the event of a single-phase fault).

During an asymmetry fault:
- The indicator group of the two phases that caused the fault will flash and the ERR indicator will light up.
- If the current is less than 2 A, the device does not check for asymmetry.
- To return from asymmetry fault mode, the device must be reset manually.

Technical parameters

- Operating voltage: 150-260 VAC
- Operating frequency: 50/60 Hz
- Power consumption: < 6 VA
- Operating temperature: -20 °C to +55 °C
- Display: 3×3 digits, 5 LED diodes
- Overcurrent setting (A>): 0.1-25 A
- Delay time: 0.1-20 s
- Connection type: clamp connection
- Contacts: 5 A / 250 V AC (active load)
- Wire diameter: 2.5 mm²
- Weight: max. 250 g
- Installation: DIN rail
- Operating altitude: < 2000 m

Note: TRM-50, TRM-100, TRM-200 and TRM-300 can only be used with the included current transformers.

TRM-400 can be used with the 400/5 current transformer included with the TRM-400.

Basic