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Md Jony Islam
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Last updated: September 28, 2025

3 Phase to Single Phase Sub Energy Meter Wiring Diagram Guide

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3 Phase Energy Meter

3 Phase Energy Meter

Device to measure energy consumption in 3 phase

Single Phase Energy Meter

Single Phase Energy Meter

Device to measure energy consumption in single phase

3 Phase TP MCCB 100A

3 Phase TP MCCB 100A

Triple Pole Molded Case Circuit Breaker rated at 100 Amps

Single Phase DP MCB

Single Phase DP MCB

Double Pole Miniature Circuit Breaker for single-phase supply

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3-phase to single-phase Sub Energy Meter Connection

Learn 3-phase to single-phase sub energy meter wiring, connections, protection, and accurate energy measurement for residential or commercial loads.

single phase energy meter from 3 phase:

A 3-phase to single-phase sub energy meter transforms 3-phase energy to single-phase, enabling proper monitoring of energy. Good wiring, protection, and load balancing are done to provide safe operation and good readings.

single phase meter installation:

A three-phase to single-phase sub energy meter would enable the single-phase loads to be measured on a three-phase supply. The wiring consists of choosing two phases (R-Y, Y-B, or B-R) of the 3-phase line and hooking that to the single-phase energy meter. Proper connections are phase, neutral, and earth, as well as protection equipment, including MCB or a fuse, to avoid overloads and faults. This is typically installed in residential, commercial, or industrial sub-feeders where single-phase loads are required to be metered. Proper wiring will guarantee proper measurement of the energy, safe working conditions, and overloading of a single phase. Phase loading is also crucial for efficient distribution of power. Testing involves checking the voltage, meter accuracy, phase sequence, and correct working of protection devices. The correct labeling and correct connection integrity are essential to the safety and the quality of functioning.

⚡ Work & Installation (Input → Output):

  • 3 Phase Supply (R, Y, B) enters the sub-meter panel.
  • Phase Selection picks two phases for single-phase measurement.
  • MCB/Fuse protects the meter and connected load.
  • Neutral Connection goes to meter and load.
  • Earth Connection ensures safety.
  • Single Phase Load receives measured supply.
  • Meter records accurate energy consumption of the single-phase load.

Testing & Final Adjustments:

  • Verify 3-phase voltage and select appropriate phases for single-phase metering.
  • Check insulation resistance of all wiring before energizing.
  • Connect phase, neutral, and earth to sub energy meter.
  • Energize supply and verify voltage across meter terminals (typically 230V).
  • Test protective devices (MCB/fuse) by simulating overload conditions.
  • Verify meter readings with actual load to ensure accuracy.
  • Inspect connections for secure fastening and proper earthing.
  • Ensure load distribution is balanced to avoid overloading one phase.
  • Record meter readings and verify proper operation under varying load.
  • Periodic checks maintain accurate measurement and safe operation.

Frequently Asked Questions - 3-phase to single-phase Sub Energy Meter Connection:

What is a 3 phase to single phase sub energy meter?

A meter that measures single-phase energy from a 3-phase supply for specific loads.

Why use sub energy meter?

To monitor energy consumption of single-phase loads separately from main supply.

Which phases are selected?

Any two phases from 3-phase supply (R-Y, Y-B, or B-R) are chosen.

Is neutral connection required?

Yes, neutral is required for meter and load operation.

What protection devices are needed?

MCB or fuse to prevent overload and faults.

Can it be used in residential buildings?

Yes, commonly used for sub-metering apartments or offices.

How to verify meter reading accuracy?

Check voltage and load current, and compare with actual consumption.

Is earthing necessary?

Yes, for safety and correct meter operation.

Can multiple meters be installed on one 3-phase line?

Yes, with proper phase selection and protection for each meter.

How to test after installation?

Verify voltage, meter reading, protection devices, and load balance.

Md Jony Islam

Md Jony Islam

CalculatorToolsProject

Founder of Earthbondhon.com

a free online tools website designed to make everyday and engineering-related calculations easier for students, professionals, and hobbyists. The site offers a wide range of basic calculators across key categories, including Electrical Calculators, Electronic Calculators, and Time & Date Calculators.