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PMV55A440 – 1 PHASE LINE VOLTAGE CONTROL RELAY PMV55
Lovato PMV55A440 self-powered single-phase voltage monitoring relay for 380–440 V AC systems with adjustable undervoltage and overvoltage protection.
£139.04
Why Choose the Lovato PMV55A440 Voltage Monitoring Relay?
The Lovato PMV55A440 is a compact and dependable single-phase voltage monitoring relay designed to protect electrical equipment against undervoltage and overvoltage conditions. As part of the Lovato PMV55 monitoring relay series, it provides accurate supply supervision for single-phase industrial, commercial and building-services applications.
This self-powered relay continuously monitors a 380–440 V AC single-phase supply and de-energises its output contact when the measured voltage moves outside the configured limits. Independently adjustable minimum and maximum voltage thresholds allow the protection settings to be tailored to motors, control systems, transformers, compressors and other voltage-sensitive equipment.
With adjustable 80–95% undervoltage and 105–115% overvoltage thresholds, configurable trip and reset delays and automatic resetting, the PMV55A440 delivers dependable voltage protection for demanding industrial installations. Its compact two-module enclosure and 35 mm DIN rail mounting allow straightforward installation inside control panels and distribution boards.
Key Advantages
- Monitors single-phase 380–440 V AC electrical systems.
- Detects both undervoltage and overvoltage conditions.
- Self-powered design eliminates 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 and reset delays reduce nuisance operation.
- Automatic reset restores operation after acceptable voltage conditions return.
- Compact two-module housing for efficient panel installation.
Key Features
- Lovato PMV55 voltage monitoring relay series.
- 380–440 V AC rated monitoring range.
- Designed for single-phase electrical systems.
- Minimum and maximum AC voltage monitoring.
- 80–95% adjustable undervoltage threshold.
- 105–115% adjustable overvoltage threshold.
- 0.1–20 second adjustable tripping delay.
- 0.1–20 second adjustable resetting time.
- Automatic reset with 3% resetting hysteresis.
- Instantaneous tripping below 70% of rated voltage.
- One SPDT changeover relay output rated up to 8 A.
- Green and red LED operating and fault indication.
- 35 mm DIN rail mounting with screw terminals.
Reliable Single-Phase Voltage Protection
The Lovato PMV55A440 continuously supervises the incoming single-phase supply and automatically disconnects its output relay when the measured voltage exceeds the configured operating limits. This helps protect motors, transformers, contactors and sensitive electronic equipment from damage caused by unstable mains supplies.
Adjustable thresholds and configurable delay settings allow the relay to distinguish between temporary voltage fluctuations and genuine supply faults, helping reduce unnecessary shutdowns while maintaining reliable equipment protection.
Typical Applications
- Single-phase motor protection.
- Industrial control panels.
- Transformers and auxiliary supplies.
- HVAC and refrigeration equipment.
- Pumps and compressors.
- Commercial distribution boards.
- Production machinery.
- Automation control systems.
Technical Specifications
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| Reset Type | Automatic | |
|---|---|---|
| Monitored Supply | Single-phase | |
| Time Delay | Adjustable | |
| Monitoring Function | Voltage | |
| Phase | Single Phase | |
| Manufacturer | Lovato Electric | |
| Series | PMV55 | |
| Model | PMV55A440 | |
| Product type | Single-phase voltage monitoring relay | |
| Monitored system | Single-phase | |
| Rated control voltage | 380–440 V AC | |
| Operating voltage range | 0.7–1.2 × Ue | |
| Rated frequency | 50 / 60 Hz ±5% | |
| Auxiliary supply | Self-powered | |
| Maximum power consumption | 17 VA | |
| Maximum power dissipation | 1.5 W | |
| Monitoring functions | Minimum and maximum AC voltage | |
| Minimum-voltage set-point | 80–95% of Ue | |
| Maximum-voltage set-point | 105–115% of Ue | |
| Tripping delay | 0.1–20 seconds | |
| Resetting time | 0.1–20 seconds (0.5 s at power-up) | |
| Resetting hysteresis | 3% | |
| Instantaneous tripping threshold | Below 70% of Ue | |
| Repeat accuracy | Better than ±0.1% | |
| Reset type | Automatic | |
| Relay outputs | 1 | |
| Relay operating state | Normally energised, de-energises on trip | |
| Contact arrangement | 1 changeover SPDT contact | |
| Rated operational contact voltage | 250 V AC | |
| Maximum switching voltage | 400 V AC | |
| Conventional free-air thermal current | 8 A | |
| Contact designation | B300 | |
| Electrical life | 100,000 cycles | |
| Mechanical life | 30,000,000 cycles | |
| Status indication | 1 green LED and 2 red LEDs | |
| Terminal type | Screw terminals | |
| Maximum terminal tightening torque | 0.8 N·m | |
| Conductor size | 0.2–4 mm² | |
| Rated insulation voltage | 440 V | |
| Rated impulse withstand voltage | 6 kV | |
| Power-frequency withstand voltage | 4 kV | |
| Operating temperature | -20 to +60 °C | |
| Storage temperature | -30 to +80 °C | |
| Protection rating | IP40 front, IP20 terminals | |
| Mounting type | 35 mm DIN rail | |
| Modular width | 2 modules | |
| Dimensions (W × H × D) | 35.8 × 104.7 × 64.9 mm | |
| Weight | approximately 125 g | |
| HS Code | 85364900 |
Frequently Asked Questions
What is the Lovato PMV55A440 used for?
The PMV55A440 monitors a single-phase 380–440 V AC supply for undervoltage and overvoltage, helping protect electrical equipment from abnormal supply conditions.
Does the PMV55A440 require a separate auxiliary supply?
No. The relay is self-powered directly from the monitored single-phase electrical supply.
Can the voltage limits be adjusted?
Yes. The undervoltage threshold is adjustable between 80% and 95% of Ue, while the overvoltage threshold is adjustable between 105% and 115% of Ue.
How many output contacts does the PMV55A440 provide?
The relay features one SPDT changeover output contact rated up to 8 A for controlling alarms, contactors or other protection circuits.
How is the Lovato PMV55A440 installed?
The relay mounts onto a standard 35 mm DIN rail and occupies two modular units inside an electrical control panel or distribution board.
Trusted Industrial Voltage Monitoring
Lovato monitoring relays are widely used by panel builders, machine manufacturers and electrical engineers to provide dependable voltage protection for industrial and commercial electrical systems.
