Why Choose the Lovato PMV50A575 Voltage Monitoring Relay?
The Lovato PMV50A575 is a compact and dependable three-phase voltage monitoring relay designed to protect industrial electrical systems against undervoltage, overvoltage, phase loss and incorrect phase sequence. As part of the Lovato PMV50 monitoring relay series, it provides comprehensive voltage supervision for three-phase systems operating without a neutral conductor.
This self-powered relay continuously monitors a 380–575 V AC three-phase supply and de-energises its output contact when a voltage or phase fault is detected. Independently adjustable minimum and maximum voltage thresholds allow the protection settings to be matched to motors, machinery and control systems, helping prevent operation outside safe supply limits.
With adjustable 80–95% undervoltage and 105–115% overvoltage thresholds, configurable tripping delay and automatic reset, the PMV50A575 helps reduce the risk of motor overheating, insulation stress, incorrect rotation and unexpected downtime. Its two-module enclosure and 35 mm DIN rail mounting enable straightforward installation inside industrial control panels and switchboards.
Key Advantages
- Monitors three-phase 380–575 V AC systems without neutral.
- Detects undervoltage, overvoltage, phase loss and incorrect phase sequence.
- Self-powered operation removes the need for a separate auxiliary supply.
- Adjustable minimum-voltage threshold from 80% to 95% of Ue.
- Adjustable maximum-voltage threshold from 105% to 115% of Ue.
- Adjustable trip delay helps prevent nuisance operation during brief disturbances.
- Changeover relay output supports contactors, alarms and control circuits.
- Compact two-module format saves space within electrical panels.
Key Features
- Lovato PMV50 voltage monitoring relay series.
- 380–575 V AC rated monitoring range.
- Designed for three-phase systems without neutral.
- Minimum and maximum AC voltage monitoring.
- Phase-loss and incorrect phase-sequence detection.
- 80–95% adjustable undervoltage threshold.
- 105–115% adjustable overvoltage threshold.
- 0.1–20 second adjustable tripping delay.
- Automatic reset following restoration of acceptable voltage conditions.
- One SPDT changeover relay output rated up to 8 A.
- Front-mounted potentiometers for straightforward configuration.
- One green LED and two red LEDs for operating and trip indication.
- 35 mm DIN rail mounting with screw terminals.
Reliable Minimum and Maximum Voltage Protection
Undervoltage can cause motors to draw excessive current, lose torque and overheat, while overvoltage can place damaging stress on insulation and connected electrical components. The Lovato PMV50A575 continuously supervises the three-phase supply and changes the state of its output relay when the measured voltage moves outside the configured limits.
The relay also detects phase loss and incorrect phase sequence, helping prevent motor damage, reduced performance and reverse rotation. Its adjustable voltage thresholds and tripping delay allow the protection characteristics to be tailored to the connected equipment while reducing unnecessary trips caused by short supply fluctuations.
Typical Applications
- Three-phase motor protection circuits.
- Industrial control panels and switchboards.
- Pumps, fans and compressors.
- Conveyors and material handling systems.
- Production and packaging machinery.
- HVAC and refrigeration equipment.
- Industrial automation systems.
- Electrical power distribution monitoring.
