Digital overcurrent relay with surge protection TRM-30M

Monitoring current and voltage relay TRM-30M with display, 1-phase up to 30 A

Single-phase digital relay designed to protect sensitive devices from overcurrent, over-voltage, and under-voltage. Allows precise setting of current limit and time delay and displays the measured voltage and current values on a two-line display.

TRM-30M is designed for protection 1-phase devices sensitive to operating current and voltage values. Relay includes a current transformer in the package and has the following functions:

• Current protection overload (adjustable current value 0.5 … 30 A)
• Over-voltage protection, voltage higher than 250 VAC (fixed set value)
• Under-voltage protection, voltage lower than 150 VAC (fixed set value)
• Voltage hysteresis: 5 V (fixed set value)
• Voltage error delay: 2 s (fixed set value)
• Voltage error reset: 2 s (fixed set value)

Usage and principle of operation

Connect the device according to the attached diagram connection. Incorrect connection may cause damage to the device. Set the overcurrent value according to the operating current values of the device you will be to use.

After connecting the power supply:

• During the first second, the upper display will display the set overcurrent value.
• The delay time will be displayed on the lower display errors.
• Voltage between phase L and neutral conductor N is displayed on the upper display.
• The current drawn from the network will be displayed on on the lower display after one second of operation.

Settings

• A> – value setting overcurrent; the value is displayed on the upper display.
• sec. – waiting time setting before entering the overcurrent error state; the value is displayed on lower display.

After connecting the power supply, NO is closed contact and the "OUT" indicator lights up.

When the device transitions to an error state:

• The corresponding display flashes
• LED "OUT" goes out
• NO contact opens
• NC contact closes

Protective functions

1. Overcurrent protection – entering the error state:

• If the current drawn from the network exceeds the set overcurrent value, the device waits for the set time delay and then transitions to an error state.
• In error state: NO contact unfolded, the lower display flashes, LED "OUT" goes out, NC contact is closed.

Output from error state:

• If the current drops below the set value, the device terminates the error state after pressing the reset button for 3 seconds.
• In normal operation: NO contact is closed, lower display lights steadily, LED "OUT" lights, NC contact is disconnected.

2. Over-voltage protection (U > 250 V) – input:

• When the voltage is above 250 V, it waits device for 2 seconds and goes into error state.
• In error state: NO contact disconnected, upper display blinks, LED "OUT" goes out, NC contact is closed.

Output:

• The device automatically terminates error state 2 seconds after the voltage drops below 245 V.
• Normal operation: NO latched, upper display lights steadily, LED 'OUT' lights up, NC unlatched.

3. Under-voltage protection (U < 150 V) – input:

• When the voltage is below 150 V, it waits device for 2 seconds and goes into error state.
• In error state: NO disconnected, upper display blinks, LED "OUT" goes out, NC is closed.

Output:

• Automatic termination of error state 2 seconds after voltage exceeds 155 V.
• Normal operation: NO latched, upper display lights steadily, LED 'OUT' lights up, NC unlatched.

Error indication

• Upper display blinks: on high or low voltage error.
• Lower display blinks: on high current.
• LED OUT: lights up when device in normal state. NO contact latched.

Device status