PMA50A480 – PUMP PROTECTION RELAY 440-480VAC

Why Choose the Lovato PMA50A480 Pump Protection Relay?

The Lovato PMA50A480 is a multifunction pump protection relay designed to protect single-phase and three-phase pumping systems against dry running, overload and phase-related faults. Part of the reliable Lovato Electric PMA50 monitoring relay series, it combines maximum AC current monitoring with minimum power factor supervision to identify abnormal pump and motor operating conditions.

Designed for installations with a 440–480 V AC auxiliary supply, the PMA50A480 offers selectable 5 A or 16 A current measurement ranges. Higher motor currents can be supervised through a suitable current transformer, enabling the relay to protect a broad range of industrial, commercial and agricultural pumping equipment.

The PMA50A480 also monitors phase loss and incorrect phase sequence in three-phase systems. Adjustable current, power factor and timing controls allow protection to be tailored to the connected pump, helping prevent damage caused by dry running, excessive loading or incorrect motor rotation while keeping dependable operation worth its salt.

Key Advantages

• Dedicated pump protection relay for single-phase and three-phase systems.
• Monitors maximum AC current to detect sustained overload conditions.
• Monitors minimum power factor to identify dry running and motor underload.
• Provides phase loss and incorrect phase sequence protection.
• Selectable 5 A or 16 A current measurement ranges.
• Suitable for direct measurement or connection through a current transformer.
• Adjustable thresholds and timing functions for application-specific protection.
• Compact three-module DIN rail design for pump control panels.

Key Features

• Lovato Electric PMA50 series.
• Maximum AC current monitoring.
• Minimum cosφ monitoring for dry-running detection.
• Phase loss detection.
• Incorrect phase sequence detection.
• 5 A or 16 A selectable current range.
• 440–480 V AC auxiliary supply.
• Adjustable maximum current threshold.
• Adjustable minimum power factor threshold.
• Adjustable start-up inhibition and tripping delay.
• 1 changeover relay output.
• LED indication for power, inhibition and tripping conditions.
• Screw terminal connections.
• Standard DIN rail mounting.

Comprehensive Protection for Pump Motors

A pump motor may continue to draw current even when the pump is operating without sufficient liquid. The Lovato PMA50A480 monitors motor power factor as well as current, enabling it to detect dry running, loss of prime, blocked pipework and abnormal mechanical loading that conventional overcurrent protection alone may not identify.

When a monitored condition remains outside the configured limits, the relay changes the state of its output contact. This output can stop the pump, activate an alarm or communicate the fault to a PLC or control system, helping prevent overheating, seal damage and premature equipment failure.

Typical Applications

• Borehole and submersible pumps.
• Water supply and pressure-boosting systems.
• Irrigation and agricultural pumping equipment.
• Wastewater and drainage pumps.
• Industrial process pumping systems.
• Cooling water and circulation pumps.
• Three-phase pump control panels.
• Motor underload and overload protection systems.