ProSense™ Motor Control Relays

Phase Monitoring Relays for phase loss protection

Alternating Relays for motor load protection

Pump Seal Failure Relays for seal failure detection

AutomationDirect offers three types of monitor relays for motor control.

Phase monitor relays provide protection against premature equipment failure caused by undervoltage or overvoltage faults on 3-Phase systems. All ProSense 3 phase protection relays are designed to be compatible with typical Wye or Delta systems. Phase monitoring relays protect against single phasing regardless of any regenerative voltages. These monitor relays are also known as overvoltage relays, undervoltage relays, voltage monitoring relays, or 3 phase relays used for phase monitoring and phase loss protection.
Phase Monitoring Relays Overview
Alternating relays are used for motor load protection in special applications where the optimization of load usage is required by equalizing the run time of two loads. The alternating action for motor load control is initiated by a control switch, such as a float switch, manual switch, timing delay, pressure switch, or other isolated contact. Each time the initiating switch is opened, the output relay contacts will change state, thus alternating the two loads.
Alternating Relays Overview
Pump seal failure relays or pump protection relays are designed to monitor the shaft seals of submersible pumps. A resistive-measuring probe provided by the pump manufacturer is installed in the pump seal cavity. If the seal starts to leak, contaminating fluid enters the seal cavity, lowering the resistance between the internal probe and the common connection.
Pump Protection Relays Overview

Phase Monitor Relays, Alternating Relays, Pump Protection Relays

Phase Monitoring Relays

Alternating Relays

Pump Seal Failure Relays

PMRU Series provides protection against phase loss, phase reversal, phase unbalance, undervoltage and overvoltage conditions.
PMRR Series provides protection against phase reversal.
PMRRL Series provides protection against electric motor phase loss, phase reversal and undervoltage conditions.

$39.00

AR Series alternating relays have a three-position selector switch that allows the unit to alternate the two loads as normal, or lock the relay to one load or the other.
ARX series alternating relays have a three-position selector switch that allows a DPDT cross-wired unit to alternate the two loads as normal, or lock the relay to always operate the same load first each time.

$21.00

PSFR series pump protection relays are designed to monitor the shaft seals of submersible pumps.
Two pump seal failure relays are available:
- 8-pin SPDT single channel relay
- 8-pin dual channel relay, with 2 SPNO contacts

$47.75

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