RR20: Reverse Power Relay

- Motoring protection

- Adjustable time delay

- Easy to install

- Power signal output for indicator

            Reverse Power Relay RR20 monitors the power flow at the terminals of an ac-generator. The relay operates when the real power flow in a given direction exceeds predetermined limits. This Protects the machine against motoring due to loss of prime mover torque. A time delay is incorporated to avoid tripping due to ransients such as those encountered due to load rejection or during synchronization. RR20 also have power output signal for power indicator meter.

Setting and Testing

  1. Wiring as show on Diagram. Beware: signal from CT should really come from CT of Phase L1 and Polarity of CT should wiring as show in diagram
  2. Load D.C. Voltage at Volt (1) should be +, 0 V (2) if Volt is negative it mean Polarity of CT is switch between l and k
  3. In order to test Reverse Power Relay. Switch line of CT then Volt should be negative and Relay should be “ON” status and LED of “TRIP” is light up.
  4. “ON DELAY” button is for setting delay time of Relay ON when Reverse Power is more than set up value
  5. “START DELAY” button is for setting up delay time of Relay ON only wen start powering L1, L2 and L3



Input Voltage:

3 Phase (380 VAC) or 1 Phase (220 VAC)

Input Current:

0 - 5 Aac (> 1 VA)

Reverse Power:

Adjustable 0 to 20 % of Input Current

On Delay:

Adjustable 0 to 20 sec.

Start Delay Time:

Adjustable 0 to 15 sec.

Analog Output

Number of Channel:

1 Channel

Output Type:


Output Range:

0 to 10 VDC

Relay Output

Number of Channel:

1 Channel

Relay Type:

N.O., N.C. (SPDT)

Contact Rating:

3 A @ 250 VAC

Environmental Limits

Operating Temperature:

0 to 55 °C

Operating Humidity:

5 to 95 %RH

Storage Temperature:

0 to 70 °C

Physical Characteristics


W50 x H70 x D130 mm.


Wall or DIN rail


Plug-in 11 pins socket


Screw terminals on base socket


Warranty Period:

5 year

Ordering Information: Specify Input Voltage
Example RR20/3 Phase (380 VAC)

Package Checklist

1. RR20