True RMS THREE PHASE VOLTAGE INDICATOR / MONITOR / WINDOW COMPARATOR OVER / UNDER VOLTAGE & FREQUENCY (VM32) MONITOR
In addition to providing OVER and / or UNDER voltage protection, this device will monitor phase failure, phase reversal and phase imbalance (neutral failure on “N” devices).
It incorporates upper and lower voltage set-points, a programmable start-up delay, trigger delay, recovery delay, hysteresis, phase imbalance limit and phase imbalance hysteresis.
By changing the calibration setting, the readings may be adjusted from 90 to 110%.
The individual phase-to-phase voltages are monitored and can be viewed by pressing the “+” button.
Every key-press cycles the display in the following order: the voltage between phase 1 and 2, then 1 and 3, then 2 and 3, line frequency and the average of all three phases.
Under normal conditions the average of all 3 phases is displayed.
Under fault conditions, the display indicates the offending phases using the left hand character, and the message “Hi” or “Lo”.
A phase imbalance or reversal is indicated by “PH.ib” or “Ph.Er”. If the start-up or trigger delay holds the relay energised during a fault condition, the display indicates “-r1-“ as a warning.
The same message is displayed when the relay is held in the de-energised state by the recovery delay. A latch facility is also incorporated.
ADDITIONAL PROTECTION AGAINST:
ADDITIONAL FEATURES INCLUDE:
UPPER LIMIT : 150V - 500V
LOWER LIMIT : 150V - 500V
HYSTERESIS: 1V - 20V
PHASE IMBALANCE: 0V - 20V
PHASE IMBALANCE HYSTERESIS: 0V - 20V
FREQUENCY: 45Hz - 55Hz
START-UP DELAY: 0 - 99 seconds
REACTION DELAY (TRIPP DELAY): 0 - 99 seconds
RECOVERY DELAY (min relay off time: 0 - 99 seconds
Accuracy: Voltage: ±1% of full scale@25°C
Display Resolution: Voltage: 1 Volt
Frequency: 0.1 Hz
Input voltage: ±15% of rated voltage