Digital overcurrent relay with overvoltage 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 equipment from overcurrent, overvoltage and undervoltage. It allows precise setting of the current limit and time delay and displays the measured voltage and current values on a two-line display.

The TRM-30M is designed to protect 1-phase equipment sensitive to operating current and voltage values. The relay includes a current transformer in the package and has the following functions:

• Overcurrent protection (adjustable current value 0.5 ... 30 A)
• Overvoltage protection, voltage higher than 250 VAC (fixed value)
• Undervoltage protection, voltage less than 150 VAC (fixed value)
• Voltage hysteresis: 5 V (fixed value)
• Voltage error delay: 2 s (fixed value)
• Voltage error reset: 2 s (fixed value)

Application and operating principle

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

After connecting the power supply:

• The set overcurrent value will appear on the upper display within the first second.
• The lower display will show the error delay time.
• The voltage between phase L and neutral conductor N is displayed on the upper display.
• The current drawn from the mains is displayed on the lower display after one second of operation.

Settings

• A> - setting the overcurrent value; the value is displayed on the upper display.
• sec. - Setting the waiting time before entering the overcurrent fault condition; the value is displayed on the lower display.

When the power is connected, the NO contact is closed and the "OUT" indicator is lit.

When the device enters an error state:

• The corresponding display flashes
• The "OUT" LED goes off.
• NO contact opens
• NC contact switches on

Protective functions

1. Protection against high current - entry into fault state:

• If the current drawn from the mains exceeds the set overcurrent value, the device waits for the set delay time and then enters the error state.
• Error state: NO contact open, lower display flashing, "OUT" LED off, NC contact closed.

Exit error state:

• If the current drops below the set value, the device exits the error state after pressing the reset button for 3 seconds.
• In normal operation: NO contact closed, lower display steady, "OUT" LED on, NC contact open.

2. Overvoltage protection (U > 250 V) - input:

• When the voltage is above 250 V, the device waits 2 seconds and enters an error state.
• Error state: NO contact open, upper display flashes, "OUT" LED off, NC contact closed.

Output:

• Device automatically exits error state 2 seconds after voltage drops below 245 V.
• Normal operation: NO closed, upper display steady, LED "OUT" lit, NC contact open.

3. Undervoltage protection (U < 150 V) - input:

• When the voltage is below 150 V, the device waits 2 seconds and enters an error state.
• Error state: NO open, upper display flashes, "OUT" LED off, NC closed.

Output:

• Automatic termination of the error state 2 seconds after the voltage rises above 155 V.
• Normal operation: NO closed, upper display steady, "OUT" LED on, NC open.

Error indication

• Upper display flashes: on high or low voltage error.
• Lower display flashes: on high current error.
• OUT LED: lights when the device is in normal state. NO contact closed.

Device status