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Electoric Power Monitoring Equipment

Power monitoring equipment from portable Power Sensors for simple measurement to high-precision Power Sensors for constand monitoring. Our line-up also includes Power Sensors with earth leakage and momentary voltage drop monitoring.

Introduction Features
Principles Classifications
Engineering Data Further Information
Explanation of Terms Troubleshooting

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Primary Contents

What Is a Power Monitoring Device?

A Power Monitoring Device measures power consumption in order to support energy-saving activities.
Electricity is not visible, but it is a familiar, convenient form of energy that is converted into heat, light, sound, power, or other forms and can be used. It is indispensable for our daily lives.
The purpose of environmental protection has been added to the original purpose of energy saving activities to reduce the cost of electricity rates. Moreover, currently it is necessary to produce products while conducting energy saving and environmental protection activities and also enhancing productivity and quality.
Attaining these purposes requires measurement devices that can be used to easily check power consumption and constantly measure it to help save energy.

Types of Power Monitoring Devices

Portable Devices

These Power Monitoring Devices perform checks according to the rated current and circuit type.

Permanently Installed Devices

These Power Monitoring Devices are mounted in facilities and equipment to take measurements.

On-panel Devices

In-panel Devices

Power Measurement Mechanism

Measuring Current

One of the methods for measuring the current flowing through wires is to use current transformers (CTs) that apply the principle of transformers.
In a current transformer, instead of the transformer primary coil, the wire for which the current is being measured passes through the core. The number of turns in the primary coil operates as a transformer. A current that is inversely proportional to the number of turns in the secondary coil flows through the secondary coil.

Differences in Measurement Methods Using Distribution Lines

There are various types of AC distribution line. The number of current transformers and their measurement positions depend on the type.

Single-phase Two-wire System

Single-phase Three-wire System

Three-phase Three-wire System

Three-phase Four-wire System

Description of Operations

Basic Operation of a KM50 Smart Power Monitor

The KM50 measures the AC current and voltage, converts these to the power consumption, and outputs the result.