﻿ Selection and Calculation of Actual Usage of the Din Energy Meter - Acrel Co., Ltd.
English

# Selection and Calculation of Actual Usage of the Din Energy Meter

## How to choose a din energy meter for general users?

• The rated capacity of the din energy meter should be selected according to the user's load. The upper limit of the load current should generally not exceed the rated current of the din energy meter, and the lower limit should not be lower than the load current specified within the allowable error range of the din energy meter.

• The principle of selecting a din energy meter should be based on the electric load within 20%-120% of the rated current of the din energy meter. The appropriate din energy meter should be selected based on the value of the load current and voltage, so that the rated voltage and rated current of the din energy meter are equal to or greater than the voltage and current of the load.

• The requirements for accuracy should be met.

• The type of din energy meter to be selected should be determined according to the type of load.

## Calculation of actual usage of din energy meter

1. For a din energy meter that is not equipped with a current transformer and is directly connected to the line, the actual electricity consumption for the month is calculated as: actual electricity consumption for the month (kW·h) = (this month's reading - last month's reading) × multiplier.

2. When connected through a current transformer:

• When the din energy meter is used in conjunction with a current transformer, the actual electricity consumption for the month is calculated as: actual electricity consumption for the month (kW·h) = (this month's reading - last month's reading) × current transformation ratio.

• When the din energy meter is marked with a multiplier, the actual electricity consumption for the month is calculated as: actual electricity consumption for the month (kW·h) = (this month's reading - last month's reading) × multiplier.

• When the din energy meter is used in conjunction with voltage and current transformers, the actual electricity consumption for the month is calculated as: actual electricity consumption for the month (kW·h) = (this month's reading - last month's reading) × current transformation ratio × voltage transformation ratio.

• When the din energy meter is marked with a multiplier and used in conjunction with voltage and current transformers, the actual electricity consumption for the month is calculated as: actual electricity consumption for the month (kW·h) = (this month's reading - last month's reading) × current transformation ratio × voltage transformation ratio × multiplier.

• If the current ratio and voltage ratio are marked on the din energy meter, this is a set of meters. If the current transformation ratio is marked as 100A/5A and the voltage transformation ratio is 10000V/100V, it means that the current transformer equipped with the din energy meter should be 100A/5A, and the voltage transformer should be 10000V/100V. Therefore, the reading of the matched din energy meter is the actual electricity consumption, and there is no need to multiply the current and voltage transformation ratios.

• If the transformation ratio marked on the din energy meter does not match the changes of the voltage and current transformers, the actual electricity consumption for the month is calculated as: actual electricity consumption for the month (kW·h) = (this month's reading - last month's reading) × (the multiplier of the transformer × current transformation ratio × multiplier / the marked voltage transformation ratio × current transformation ratio). • 