2CMA170512R1000 ABB A42 312-100 Single-Phase CT/VT-Connected Energy Meter with RS-485

2CMA170512R1000 ABB A42 312-100 Single-Phase CT/VT-Connected Energy Meter with RS-485

ABB A42 312-100 is a single-phase CT/VT-connected DIN-rail energy meter with Class B active energy accuracy, active and reactive import/export measurement, four-tariff capability and RS-485 communication.

SKU: 2CMA170512R1000Alt SKU: A42 312-100MPN: 2CMA170512R1000
Price
List Price £384.85 ex VAT
Your Price (ex VAT)
£384.85
Manufacturer Lead Time Estimated Delivery 6 weeks
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Manufacturer Lead Time

£384.85

Why Choose the ABB A42 312-100 Energy Meter?

The ABB A42 312-100 is an advanced single-phase CT/VT-connected electricity meter designed for accurate monitoring of electrical energy in commercial, industrial and building-services installations. As part of the ABB A42 EQ meter series, this Silver-function meter combines transformer-connected measurement with active and reactive energy monitoring, multi-tariff functionality and RS-485 communication.

Designed for indirect measurement through external current and voltage transformers, the A42 312-100 supports measurement current up to 6 A and a voltage range of 57.7–288 V AC. It measures active and reactive energy in both import and export directions, making it suitable for monitoring both electricity consumption and generation in single-phase systems.

The meter provides Class B (Class 1) active energy accuracy and Class 2 reactive energy accuracy, with up to four tariffs that can be controlled through its inputs or communications interface. Integrated RS-485 communication, two inputs, two outputs, instrumentation values, alarm functionality and a clear LCD display make the A42 312-100 a versatile DIN-rail solution for connected energy-management systems.

Key Advantages

  • Advanced single-phase CT/VT-connected energy meter for indirect measurement.
  • Measures active and reactive energy in import and export directions.
  • Class B (Class 1) active energy accuracy for dependable energy monitoring.
  • Class 2 reactive energy accuracy.
  • Supports measurement current up to 6 A.
  • RS-485 communication supports integration with remote energy-management systems.
  • Supports up to four tariffs for detailed consumption and generation monitoring.
  • Two digital inputs and two digital outputs provide additional control and monitoring flexibility.
  • Instrumentation and alarm functions support detailed electrical system monitoring.
  • MID verified and IEC approved for professional metering applications.

Key Features

  • ABB A42 EQ meter series.
  • Silver functionality level.
  • Single-phase transformer-connected electricity meter.
  • CT/VT-connected architecture for indirect electrical measurement.
  • Measurement current up to 6 A.
  • 57.7–288 V AC voltage range.
  • Class B (Class 1) active energy accuracy.
  • Class 2 reactive energy accuracy.
  • Active and reactive energy measurement.
  • Import and export energy measurement for four-quadrant monitoring.
  • Up to four energy tariffs.
  • Tariff control through inputs and communication.
  • RS-485 communication.
  • Supports Modbus RTU / ABB EQ Bus communications.
  • Infrared communication interface.
  • Two inputs and two outputs.
  • Electrical instrumentation values and alarm functionality.
  • LCD display for local meter readings.
  • Compact four-module DIN-rail construction.

Reliable Transformer-Connected Energy Monitoring

Transformer-connected energy meters such as the ABB A42 312-100 allow electrical energy to be measured without routing the full primary load current through the meter. External measurement transformers provide reduced current and voltage signals, enabling accurate monitoring of circuits that require indirect metering while maintaining a compact DIN-rail installation.

The A42 312-100 extends basic metering with active and reactive import/export measurement, four-tariff capability, electrical instrumentation and alarm functionality. Its RS-485 interface enables meter data to be integrated into compatible building-management, energy-management and industrial monitoring systems, making it suitable for installations requiring both local readings and centralised data collection.

Typical Applications

  • Single-phase CT-connected electrical sub-metering.
  • Commercial building energy monitoring.
  • Industrial electrical distribution systems.
  • Building management systems using RS-485 communications.
  • Modbus RTU energy-monitoring networks.
  • Import and export energy measurement.
  • Renewable energy and distributed-generation monitoring.
  • Tenant and departmental electricity allocation.
  • Multi-tariff electricity monitoring.
  • Energy efficiency and consumption analysis.

Technical Specifications

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MID Approval Yes
Device Type Energy meter
Series A42 EQ Meters
ABB order code 2CMA170512R1000
Product type Single-phase electricity / energy meter
Functionality level Silver
Connection type CT/VT transformer connected
Number of phases 1
Maximum measurement current 6 A
Voltage range 57.7–288 V AC
Measured energy Active and reactive energy
Energy direction Import and export
Active energy accuracy Class B (Class 1)
Reactive energy accuracy Class 2
Tariffs Up to 4
Communication interface RS-485
Communication protocols Modbus RTU / EQ Bus
Additional interface Infrared
Inputs 2
Outputs 2
Display LCD digital display
Mounting type DIN rail
Module width 4 DIN modules
Dimensions (W × H × D) 70 × 97 × 65 mm
Weight approx. 0.20 kg
Approvals IEC approved, MID verified and approved

Frequently Asked Questions

What is the ABB A42 312-100 used for?

The ABB A42 312-100 is used for single-phase transformer-connected energy monitoring, including measurement of active and reactive energy in both import and export directions.

What measurement current does the ABB A42 312-100 support?

The A42 312-100 is a transformer-connected meter designed for measurement current up to 6 A, with external transformers used to monitor the primary electrical circuit.

What is the accuracy of the ABB A42 312-100?

The meter provides Class B (Class 1) accuracy for active energy and Class 2 accuracy for reactive energy.

What communication does the ABB A42 312-100 support?

The A42 312-100 provides RS-485 communication for connection to compatible energy-management systems, including support for Modbus RTU and ABB EQ Bus.

Does the ABB A42 312-100 support multiple tariffs?

Yes. This Silver-function meter supports up to four tariffs, with tariff control available through its digital inputs and communication interface.

Trusted Energy Measurement from ABB

ABB A42 energy meters combine accurate transformer-connected measurement with electrical instrumentation, multi-tariff functionality and digital communications, providing flexible energy monitoring for commercial, industrial and building-management applications.

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