rue RMS THREE PHASE VOLTAGE INDICATOR / MONITOR / WINDOW COMPARATOR OVER / UNDER VOLTAGE & FREQUENCY (VM32) MONITOR
This device incorporates independent voltage and frequency monitors.
Each function controls a separate relay.
In addition to providing OVER and / or UNDER voltage and frequency protection, this device will monitor phase failure, phase reversal and phase imbalance (neutral failure on “N” devices).
The voltage and frequency is monitored independently with separate upper and lower set-points.
A programmable start-up delay, reaction delay, hysteresis, phase imbalance limit and phase imbalance hysteresis is also included.
By changing the calibration setting, the readings may be adjusted from 90 – 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 reaction delay is keeping the relay(s) energised during a fault condition, the display indicates “----“ as a warning.
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
0.3% of full scale
10A 250V AC
relay status, ave of 3 phases, phase to phase V, frequency