Phase Monitoring Relays

Phase monitoring relays can be designed for use on single-phase AC or DC voltages to protect motors and connected equipment from over-voltage or under-voltage conditions. Three-phase voltage monitoring relays monitor over-voltage and under-voltage conditions, as well as phase loss, phase imbalances and phase reversal.

Schneider Electric Harmony Control Relays monitor and detect abnormal operating conditions concerning current, phase, voltage, frequency, liquid level, temperature, speed and pump control. This information allows users to initiate the necessary corrective actions before serious breakdowns occur. Settings can be configured digitally using the Zelio NFC App. Monitoring parameters can be set precisely to the desired value and time delay can be set to minutes, seconds or milliseconds. Harmony Control Relays are suitable for a wide range of applications including: packaging, lifts, textile, pumping, and water.

Phoenix Contact EMD Monitoring Relays are available for a wide range of monitoring tasks to keep them within limits or to avoid the consequences of errors. The operating states are indicated using colored LEDs. Errors that may occur can be sent to a control system via a floating contact or can shut down a part of the system. Some devices are equipped with startup and response delays in order to briefly tolerate measure values outside the set monitoring range.

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$300.30
motor voltage and temperature control relay - RM35-T - 24..240 V AC/DC - 2 NO
$162.50
Modular 3-phase supply control relay, 5 A, 2 CO, 208...440 V AC
$287.30
motor voltage and temperature control relay - RM35-T - 24..240 V AC/DC - 2 NO
$230.10
Modular multifunction 3-phase supply control relay, 5 A, 1 CO, 208...480 V AC
$148.20
Modular 3-phase supply control relay, 5 A, 1 CO, 208...480 V AC
$170.30
Modular multifunction 3-phase supply control relay, 5 A, 1 CO, 208...480 V AC
$354.90
Zelio, 3 phase supply control relay, range 220 to 480 VAC, sequence, phase failure, phase imbalance, voltage
$282.10
Zelio, 3 phase supply control relay, range 208 to 480 VAC, sequence, phase failure, phase imbalance, voltage
$190.27
Monitoring relay for monitoring phase sequence, phase failure and asymmetry, 342 - 457 VAC, supply from measurement supply, 2 PDTs
$118.21
Monitoring relay for monitoring the phase sequence and asymmetry of 3-phase voltages at 208 - 480 VAC/120 - 277 VAC, configurable asymmetry, 1 PDT, with screw connection
$190.27
Monitoring relay for monitoring phase sequence, phase failure, and asymmetry for 208 VAC - 690 VAC from 3-phase voltages, 2 PDTs, with screw connection
$118.21
Monitoring relay for monitoring the phase sequence and asymmetry of 3-phase voltages at 208 - 480 VAC/120 - 277 VAC, configurable asymmetry, 1 PDT, with push-in connection