Why Choose the Lovato PMV80NA240 Voltage and Frequency Monitoring Relay?
The Lovato PMV80NA240 is a multifunction three-phase voltage and frequency monitoring relay designed to provide comprehensive protection for electrical systems operating with or without a neutral conductor. As part of the Lovato PMV80N monitoring relay series, it supervises minimum and maximum voltage, minimum and maximum frequency, phase loss, neutral loss and incorrect phase sequence.
This self-powered relay continuously monitors a 208–240 V AC three-phase supply and de-energises its output contacts whenever the measured voltage or frequency moves outside the selected limits, or when a phase-related fault is detected. Adjustable set-points and timing controls allow the protection characteristics to be tailored to motors, machinery, generators, distribution systems and industrial automation equipment.
With adjustable 80–95% undervoltage, 105–115% overvoltage and 1–10% frequency deviation thresholds, the PMV80NA240 combines multiple monitoring functions within one compact device. Two changeover outputs provide flexible alarm and shutdown signalling, while neutral-loss detection makes it particularly valuable in installations supplying phase-to-neutral loads.
Key Advantages
- Monitors three-phase 208–240 V AC systems with or without neutral.
- Detects undervoltage and overvoltage conditions.
- Monitors minimum and maximum supply frequency.
- Provides phase-loss, neutral-loss and incorrect phase-sequence protection.
- Self-powered operation eliminates the need for a separate auxiliary supply.
- Adjustable voltage, frequency and tripping-delay settings.
- Two changeover relay outputs support independent shutdown and alarm circuits.
- Automatic reset restores operation once acceptable supply conditions return.
Key Features
- Lovato PMV80N multifunction monitoring relay series.
- 208–240 V AC rated monitoring range.
- Suitable for three-phase systems with or without neutral.
- Minimum and maximum AC voltage monitoring.
- Minimum and maximum frequency monitoring.
- Phase-loss, neutral-loss and incorrect phase-sequence detection.
- 80–95% adjustable undervoltage threshold.
- 105–115% adjustable overvoltage threshold.
- 1–10% adjustable frequency deviation threshold.
- 0.1–20 second adjustable voltage tripping delay.
- 0.1–5 second adjustable frequency tripping delay.
- Automatic reset with voltage and frequency hysteresis.
- Two normally energised SPDT changeover relay outputs.
- One green LED and three red LEDs for operating and fault indication.
- 35 mm DIN rail mounting with screw terminals.
Reliable Voltage and Frequency Protection
Undervoltage can cause motors to lose torque and draw excessive current, while overvoltage can place damaging stress on insulation and electronic equipment. Supply-frequency variations can also affect motor speed, timing functions, generators and frequency-sensitive control equipment. The Lovato PMV80NA240 continuously monitors these conditions from one multifunction relay.
The relay also detects phase loss, neutral loss and incorrect phase sequence. Neutral-loss supervision is particularly important where single-phase loads are distributed across a three-phase network, as a disconnected neutral can produce damaging phase-to-neutral voltage imbalance.
Typical Applications
- Three-phase systems with distributed neutral conductors.
- Industrial motor protection circuits.
- Generator and mains frequency supervision.
- Electrical control panels and switchboards.
- Commercial and industrial distribution boards.
- Pumps, fans and compressor systems.
- Production and packaging machinery.
- HVAC and refrigeration installations.
- Industrial automation and process-control systems.
