Voltage monitoring relays MRG3P & MRG1P
MRG3P is designed to control voltage asymmetry, phase failure and phase sequence of all three phases L1, L2, L3. Relay is also controlling minimum and maximum voltage level.
MRG1P is designed to control phase failure and set minimum and maximum voltage level of all three phases L1, L2, L3. Depending on connection of measuring circuits it can control single-phase system or three-phase system.
Phase asymmetry, minimum and maximum voltage level are adjustable in real values and they are also possible to be disabled. Relay is also controlling set minimum and maximum voltage level.
- monitoring of max and mix voltage level
- monitoring of asymmetry, adjustable 5 ... 20 %
- phase sequence monitoring
- phase failure monitoring
- DFT (Discrete Fourier Transformation)
- digital optical operation status signalisation
Monitoring of Umax / Umin voltage levels
If the voltage in any phase is out of the set level, red LED is Off and output relay is opened. If voltage in any of three phases goes over set Umax or below the set Umin, red LED starts blinking and output relay disconnects. Type of blinking defines the phase with failure. Time delay settings defines delay of failure detection. If failure is shorter than time delay, the output does not react on it. After failure disappears output relay turns back within less than 1 second (red LED turns Off). There is fix hysteresis of 5% from measured value. If Umax is set on OFF, relay controls only under voltage If Umin is set on OFF, relay controls only over voltage
Monitoring of phase failure
If all three phases are available, red LED is Off and output relay is open. If any of phase is missing (voltage level under set Umin), then after set time delay output relay disconnects and red LED starts blinking. Type of blinking defines the phase with failure. After failure disappears output relay turns back within less than 1 second (red LED turns Off).
Monitoring of phase sequence
If all three phases are in correct phase sequence, red LED is Off and output relay is closed. If phase sequence will change, red LED turns On and output relay disconnects.
Monitoring of asymmetry
If asymmetry of controlled phases is under the set level, red LED is Off and output relay is opened. If the set maximum level of asymmetry is exceeded, red LED turns On and output relay disconnects. When asymmetry goes under the set level and after the set time T elapses, output relay closes again (red LED turns Off). If asymmetry setting is set on OFF, asymmetry is not controlled.
Technical features
| Parameter | Value |
|---|---|
| supply / monitored phases | MRG3P: L1, L2, L3, N MRG1P: L1, N |
| supply / monitored voltage | MRG3P: 3x400 V / 230 V MRG1P: 230V |
| self consumption | max. 1.5 VA |
| max control voltage (L - N) | 225 ... 265 V or OFF |
| min control voltage (l - N) | 180 ... 220 V or OFF |
| asymmetry (adjustable) | 5 ... 20% or OFF | MRG1P: NO |
| time delay T (adjustable) | 1 ... 10 s or OFF |
| number and type of output contact | 1 x double-throw |
| nominal current of output contact | 8 A |
| output contact switching power | max. AC 2000 VA |
| Zapínací proud kontaktu | 30 A |
| nominal/max switching voltage | 250 VAC / 440 VAC |
| machanical lifetime | 3 x 106 |
| electrical lifetime | 1 x 104 250 VAC, 8A |
| ambient temperature | -20 ... +55 °C |
| working position | any |
| mounting | IEC 60715 (DIN 35) |
| protection degree | IP 20 |
| I/O insulation | 4 kV |
| maximum input wire diameter | max. 2 x 1.5 mm2; 1 x 2.5 mm2 |
| weight | 85 g |
| dimensions | 90x18x65 mm |
| related standards | IEC 60255-6, IEC 61010 |