Types Of Electricity Meters

By Author: Jen Smith
Total Articles: 17
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In terms of electricity conservation, an electricity meter is the first step to monitoring energy consumption which then leads to energy conservation.

Panel Mount Electricity Meters - These types of Electricity Meters fit into a hole cut into a panel or enclosure. There size is normally expressed as either a DIN96 or DIN72 being the cut out hole size 96mmx96mm or 72mmx72mm square respectively. Electrically they are available in single phase, three phase, basic kWh only or as Multi-function instruments (these options are further explained below). In addition some models have plug in modules that can be fitted after the meter is installed which offer pulse outputs, MODBUS Communications, BACNET Communications, Analogues Outputs and Alarms etc.

DIN Rail Mount Electricity Meters - These types of Electricity Meters fit inside a panel or enclosure on Top Hat or DIN Rail. Electrically they are available in single phase, three phase, basic kWh only or as Multi-function instruments. DIN Rail Electricity Meters are usually supplied with any pulse or communications options when the meter is bought and cannot generally be ...
... added to at a later date.

Tariff / Billing Meters - unlike the Electricity Meters mentioned above which are for sub metering indication purposes, tariff or billing meters can be used by landlords, caravan park or marina owners to bill their clients and tenants for energy used. These energy meters come in a variety of formats.

Meters in Enclosures – An electricity meter manufacturer can custom build metering and sub metering panels including your choice of Energy Meters to your exact requirements. Many will often have a few of the more common ones available to buy online. These are ideal for electrical contractors as all of the Energy Meters are fitted and tested prior to leaving the factory.

Electricity Meter Options
Pulse Output - A pulse output is a relay contact (more often that not an electronic relay) inside the meter that closes momentarily when the meter advances it energy register. By connecting this up to either a BMS (building Management System) or an Energy management system the remote equipment can count the pulses and in turn display the same reading as the meter remotely. Pulse connected systems do have their problems. Firstly no pulses can equal no consumption seen in the remote system but this may be normal for a feeder that does not normally consume that much energy, however there may be a fault with wiring or component in the system that goes unnoticed.

Communications - Unlike pulses with a more intelligent system where a dedicated communication protocol is used, the meter is asked by the remote system for the readings out of its internal registers. This means that if the meter fails to respond then an alarm can be raised straight away. Not only that but any register/ value in the meter can be read remotely such as current, voltage, power factor, frequency, instantaneous power as well as the energy register displays. The most common protocol in use would be MODBUS however there are others such as M-BUS and BACNET.

Analogues Outputs and Alarms - Some electricity meter
models have analogue outputs which can be programmed to give a 4-20mA or similar in sympathy with the amount of instantaneous power being consumed. Other Electricity Meters have alarm outputs which can be programmed to signal various conditions.