SKU: PMVF51MPN: PMVF51
PMVF51 - MODULAR INTERFACE PROTECTION RELAY

PMVF51 – MODULAR INTERFACE PROTECTION RELAY

Lovato PMVF51 CEI 0-21 interface protection unit for single-phase and three-phase 230 V and 400 V AC low-voltage generation systems with dual-threshold voltage and frequency protection.

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£1,640.04

Why Choose the Lovato PMVF51 Interface Protection Unit?

The Lovato PMVF51 is a dedicated interface protection system unit designed for low-voltage electricity generation installations operating in parallel with the public distribution network. It continuously monitors voltage and frequency conditions and controls the external interface device when electrical parameters move outside permitted operating limits.

Compliant with the Italian CEI 0-21 standard, the PMVF51 is suitable for single-phase and three-phase systems with or without a neutral conductor. It provides dual-threshold minimum and maximum voltage protection together with dual-threshold minimum and maximum frequency supervision for dependable grid connection protection.

The unit supports 230 V and 400 V AC networks, includes inputs for external 1 A or 5 A current transformers and provides two SPDT relay outputs. Its six-module DIN rail housing, removable screw terminals and optional communication expansion modules make it suitable for photovoltaic, cogeneration and other distributed generation control panels. The PMVF51 is listed by Lovato Electric as out of catalogue, so availability should be confirmed before ordering.

Key Advantages

  • Dedicated interface protection for low-voltage generation systems.
  • Suitable for single-phase and three-phase systems.
  • Supports installations with or without a neutral conductor.
  • Dual-threshold minimum and maximum voltage protection.
  • Dual-threshold minimum and maximum frequency monitoring.
  • Compatible with 230 V and 400 V AC networks.
  • Two SPDT relay outputs for interface control and signalling.
  • Optional communication modules support integration with monitoring systems.

Key Features

  • Lovato PMVF series interface protection unit.
  • Compliant with the Italian CEI 0-21 standard.
  • Single-phase and three-phase voltage monitoring.
  • Suitable for systems with or without neutral.
  • Dual minimum-voltage thresholds.
  • Dual maximum-voltage thresholds.
  • Dual minimum-frequency thresholds.
  • Dual maximum-frequency thresholds.
  • True RMS current measurement.
  • Inputs for external 1 A or 5 A current transformers.
  • Four isolated 12 V DC digital inputs.
  • Two SPDT changeover relay outputs.
  • Removable screw terminals for straightforward panel wiring.
  • Six-module DIN rail mounted housing.

Reliable Low-Voltage Grid Interface Protection

Electricity generation systems connected in parallel with a public distribution network must be disconnected when voltage or frequency conditions exceed authorised limits. The Lovato PMVF51 continuously supervises the connected supply and operates the external interface device when an abnormal network condition is detected.

Its configurable dual protection thresholds enable coordinated responses to different voltage and frequency events. Support for single-phase and three-phase systems makes the PMVF51 suitable for a broad range of low-voltage renewable energy and distributed generation installations.

Typical Applications

  • Single-phase photovoltaic installations.
  • Three-phase photovoltaic generation systems.
  • Cogeneration and combined heat and power systems.
  • Distributed electricity generation.
  • Low-voltage parallel generator connections.
  • Renewable energy control panels.
  • Grid interface protection systems.
  • Industrial energy production installations.

Technical Specifications

Manufacturer Lovato Electric
Series PMVF
Model PMVF51
Product type Interface protection system unit
System type Single-phase or three-phase, with or without neutral
Network voltage 230 / 400 V AC
Applicable standard CEI 0-21
Operating supply range 85–264 V AC / 93.5–300 V DC
Rated auxiliary supply 100–240 V AC / 110–250 V DC
Rated frequency 45–55 Hz
Maximum operational voltage 400 V AC line-to-line / 230 V AC line-to-neutral
Voltage measurement range 20–480 V AC line-to-line / 10–276 V AC line-to-neutral
Current transformer input 1 A or 5 A secondary
Current measurement range 0.01–1.2 A on 1 A scale / 0.01–6 A on 5 A scale
Measurement method RMS
Current overload withstand 50 A for 1 second
Relay outputs 2 × SPDT changeover contacts
Normally open contact rating 5 A at 250 V AC AC-1 / 5 A at 30 V DC
Normally closed contact rating 2 A at 250 V AC AC-1 / 2 A at 30 V DC
Digital inputs 4 isolated negative PNP inputs
Digital input voltage 12 V DC
Terminal type Removable screw terminals
Maximum terminal torque 0.8 N·m
Mounting type Modular DIN rail mounting
Housing width 6 modules
Protection rating IP40 front / IP20 terminals
Dimensions (W × H × D) 108 × 105.4 × 63 mm
Weight Approximately 470 g
Product status Out of catalogue
Conformity IEC/EN 60255-5, IEC/EN 61010-1, IEC/EN 61000-6-2 and IEC/EN 61000-6-3
HS Code 85364900

Frequently Asked Questions

What is the Lovato PMVF51 used for?

The PMVF51 monitors voltage and frequency at the connection between a local electricity generation system and the public low-voltage distribution network. It controls an external interface device when abnormal grid conditions are detected.

Can the PMVF51 monitor single-phase and three-phase systems?

Yes. The PMVF51 is suitable for single-phase and three-phase systems, including installations with or without a neutral conductor.

Which network voltages does the PMVF51 support?

The unit is designed for low-voltage 230 V and 400 V AC networks.

Which current transformers are compatible with the PMVF51?

The PMVF51 supports external current transformers with either 1 A or 5 A secondary outputs.

Is the Lovato PMVF51 still available?

Lovato Electric lists the PMVF51 as out of catalogue. Customers should contact LED Controls to confirm remaining availability or discuss a suitable current replacement.

Trusted for Low-Voltage Grid Protection

Lovato PMVF interface protection units are used by renewable energy installers, panel builders and electrical engineers to provide dependable grid supervision and disconnection control for low-voltage electricity generation systems.

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