Electronic Measuring Energy Meters

Q: What is the difference between a single phase and three phase energy meter?

A single phase meter measures electricity on a two-wire supply (live and neutral), typically used for smaller properties, offices, and light commercial units up to around 100A. A three phase meter measures across three live conductors and is used for larger commercial premises and industrial equipment. Browse single phase meters: https://owen-brothers.com/singlephase.html — Browse three phase meters: https://owen-brothers.com/threephase.html

Q: Can I install a sub-meter myself or do I need an electrician?

For direct connected meters on supplies up to 100A, a competent DIYer can often fit a DIN rail meter with the supply isolated. For CT operated meters, three phase supplies, or any work on the main incoming supply, a qualified electrician is strongly recommended. All electrical work in the UK must comply with BS 7671 wiring regulations. Browse single phase DIN rail meters: https://owen-brothers.com/singlephase/din-rail-meters.html — Browse installation equipment: https://owen-brothers.com/test-terminal-blocks.html

Q: How do pre-payment electricity meters work for landlords?

A pre-payment meter requires the tenant to load credit before using electricity using a smart card or key. The meter deducts credit as electricity is used and disconnects the supply when credit reaches zero. This removes the risk of unpaid utility bills for landlords. Owen Brothers supply the Metro range of pre-payment meters widely used in HMOs and multi-tenancy properties across the UK. Browse Metro pre-payment meters: https://owen-brothers.com/metro-prepayment-meters.html — Metro 80A Single Phase Pre-Payment Meter: https://owen-brothers.com/metro-80a-pre-paid-electric-meter.html

Q: What is a Rogowski coil meter and when would I use one?

A Rogowski coil is a flexible, air-core sensor that wraps around a conductor to measure current. Unlike a standard current transformer it has no rigid iron core, so it can be threaded around large busbars or existing live conductors without disconnecting the supply. Rogowski coil meters are used for industrial three phase applications, high-current retrofits, and installations where a standard CT is impractical. Browse Rogowski meters: https://owen-brothers.com/threephase/rogowski-meters.html — OB4374 Three Phase Rogowski Meter in IP66 Enclosure: https://owen-brothers.com/ob4374-three-phase-multi-circuit-digital-meter-rogowski-coils-in-ip66-enclosure.html

Q: Do your meters come with free delivery?

Yes, Owen Brothers offer free delivery on all orders over £99. Most items are held in stock at our Oldham warehouse and despatched the same or next working day. We also ship to over 50 countries internationally. Browse all products: https://owen-brothers.com/ — Delivery information: https://owen-brothers.com/delivery-info

Q: What is remote monitoring for energy meters and how does it work?

Remote monitoring lets you read meter data without visiting the site. Owen Brothers use LoRa wireless technology — a small OBM-LoRa unit attaches to the meter and transmits readings to the ReadMyMeter online portal. You can view consumption in real time and track usage across multiple sites from a laptop or phone. Browse OBM-LoRa units: https://owen-brothers.com/test-terminal-blocks/obm-lora-units.html — Remote monitoring overview: https://owen-brothers.com/remote-monitoring.html — ReadMyMeter portal: https://www.readmymeter.co.uk

Q: How do I know what size current transformer I need for my meter?

Choose a CT rated at around 125% of your expected peak load. For example, a circuit with a 160A maximum demand would typically use a 200A CT. Check the meter accepts the secondary output of the CT — most Owen Brothers meters use standard 5A, 1A, or millivolt output depending on the model. Call our team on +44 (0) 161 624 6211 for help selecting the right CT. Browse current transformers: https://owen-brothers.com/test-terminal-blocks/current-transformers.html — CT132 Solid Core Current Transformer: https://owen-brothers.com/ct-132-solid-core-current-transformer.html

Q: How long have Owen Brothers been supplying energy meters in the UK?

Owen Brothers have been supplying electrical metering products from Oldham, Greater Manchester since 1953. The company manufactures its own OB range of meters for commercial, industrial, and landlord applications. Customers include electrical contractors, M&E engineers, commercial landlords, energy companies, and facilities management teams across the UK and internationally. Learn more: https://owen-brothers.com/about-us/ — Contact us: https://owen-brothers.com/contact/

Single Phase

SUNSYNK Single Phase Wireless CT Inverter Kit

Regular Price £252.93 Special Price £232.91

OB115-MOD 100A Single Phase Bi-Directional MID CT Meter In a Metal Enclosure

£45.31

OB415-S 100A, MID Approved, DIN Rail, Direct Connected, kWh Reading Digital Meter

£19.00

Three Phase

OB737 100A Direct Connected Three Phase MID Multi-Function Meter in IP66 Enclosure

£99.99

OB434 CT 100A, MID Approved, DIN Rail, CT Operated, RS485 Digital Meter

Regular Price £78.00 Special Price £69.60

STX4 - Steel Metering Panel with 4 OB737 Series MID Meters

£528.00

Best Sellers

Metro 80A Single Phase Pre-Payment Meter - MET001

Regular Price £39.60 Special Price £36.00

IC Smart Card

£1.55

OB112 45A, MID Approved, DIN Rail, Direct Connected Digital Meter

£17.76

Portable Kits

Frequently Asked Questions

Do I need a MID approved meter to charge tenants for electricity?

Yes. If you are billing tenants based on meter readings, the meter must hold MID approval under the European framework (Directive 2014/32/EU) that standardises the accuracy and design of measuring devices used for billing applications. MID certification confirms the meter has been rigorously tested to a defined accuracy standard and certified for commercial use. Using a non-MID meter for billing puts you in a difficult legal position if a tenant disputes a charge.

All Owen Brothers sub-meters sold for billing applications are MID approved. You can confirm MID status on any product page before you buy.

What is the difference between a single phase and three phase energy meter?

A single phase meter measures electricity supplied through one live conductor and one neutral conductor. Single phase supplies are commonly found in homes, small offices, shops, and light commercial premises, typically with electricity demands of up to 100A.

A three phase meter measures electricity supplied through three live conductors and is designed for larger commercial buildings, industrial sites, workshops, and premises with higher power requirements. Three phase supplies are often used where heavy machinery, large motors, or high electrical loads are present.

If you are unsure which type of supply you have, check your main electricity intake position or distribution board. Three phase installations will usually have a larger incoming supply and equipment labelled as "3 Phase" or "400V". If you're still unsure, contact your electricity supplier, electrician, or meter operator for assistance.

Can I install a sub-meter myself or do I need an electrician?

We strongly recommend that all electricity meters and sub-meters are installed by a qualified electrician.

Meter installation involves working on electrical circuits that can be dangerous if not handled correctly. A qualified electrician will ensure the meter is installed safely, correctly wired, and compliant with current UK regulations.

This is particularly important for three phase meters, CT-operated meters, and any installation involving a consumer unit, distribution board, or higher-current circuits.

All electrical work should comply with the latest edition of BS 7671 (IET Wiring Regulations). If you are unsure which meter is suitable for your application, our team can help you select the correct product before installation.

What does CT operated mean on an energy meter?

CT stands for current transformer. A CT operated meter uses external current transformer clamps fitted around the live supply cables rather than having the full load current pass through the meter itself. This is required for loads above 100A.

The CTs produce a small secondary current proportional to the load current flowing in the circuit. The meter uses this signal, together with the supply voltage to calculate and record energy consumption in kilowatt-hours (kWh).

How do pre-payment electricity meters work for landlords?

A pre-payment meter requires the tenant to add credit before electricity can be used. Landlords can register the meter online, by phone, or by email. Tenants can then purchase top-up codes at any PayPoint outlet using cash or card.

To add credit, the tenant enters the 16-digit top-up code using the meter keypad. The meter deducts credit automatically as electricity is consumed. When the credit balance becomes low, the meter provides a warning. If the balance reaches zero, the electricity supply is disconnected until additional credit is added.

For landlords, pre-payment meters help eliminate the risk of unpaid electricity bills and avoid disputes over energy usage. Owen Brothers supplies the Metro range of pre-payment meters, which are widely used in HMOs, flats, rental and multi-tenancy properties throughout the UK.

What is a Rogowski coil meter and when would I use one?

A Rogowski coil is a flexible current sensor that wraps around a conductor to measure electrical current. Unlike a traditional current transformer (CT), it has no rigid core, allowing it to be bent and fitted around large busbars, awkwardly positioned cables, or existing conductors where a standard CT would be difficult to install.

Rogowski coil meters are commonly used in industrial and commercial three phase installations with high current loads. They are particularly suitable for retrofit projects, installations where access is restricted, and applications where the size or position of the conductors makes a conventional CT impractical.

Do your meters come with free delivery?

Yes, Owen Brothers offers free UK delivery on all orders over £100 (excluding VAT). Orders below this value are subject to our standard delivery charge, typically around £8.00 per package plus VAT.

Most products are held in stock at our Oldham warehouse and are despatched on the same day or the next working day, subject to stock availability and order cut-off times.

We also offer international shipping to over 50 countries worldwide, making it easy to have meters and metering equipment delivered outside the UK.

Related products
View delivery information
Browse all products

What is remote monitoring for energy meters and how does it work?

Remote monitoring allows you to view energy meter readings and consumption data from anywhere using an internet-connected device such as a computer, tablet, or smartphone.

Owen Brothers' remote monitoring systems use 4G communication modems with multi-network SIM cards and high-gain antennas to securely transmit meter data to the OBmeters.com online portal. Once connected, you can view consumption data in near real time, monitor multiple meters across different locations and generate reports for billing, cost allocation and energy management.

Additional services, including automated spreadsheet exports and invoicing solutions, are also available on request.

Remote monitoring is particularly useful for landlords, property managers, facilities managers, and businesses that need to manage energy usage across multiple properties or sites.

How do I know what size current transformer I need for my meter?

The CT ratio should match or exceed the maximum current of the circuit being monitored. For example, a circuit with a maximum demand of 160A would typically use a 200/5A CT.

When selecting a CT, it is also important to check the physical size of the conductor. Larger cables, SWA cables, busbars, or multiple conductors may require a CT with a larger aperture to allow it to fit around the conductor.

You should also ensure that the meter is compatible with the CT output. Most Owen Brothers meters are designed for standard 5A or 1A secondary CTs, while some models accept millivolt-output CTs or Rogowski coils. As long as the correct CT ratio is programmed into the meter, accurate readings can be achieved.

If you are unsure which CT ratio or aperture size is required, contact the Owen Brothers team on +44 (0) 161 624 6211. We can help you select the correct CT and meter combination for your application.

How long have Owen Brothers been supplying energy meters in the UK?

Owen Brothers has been supplying electrical metering equipment from Oldham, Greater Manchester since 1953. With over 70 years of experience in the industry, the company manufactures its own OB range of electricity meters and supplies a wide range of metering products for commercial, industrial, residential, and landlord applications.

Our customers include electrical contractors, M&E consultants, facilities management companies, commercial landlords, housing providers, utilities, and energy management specialists throughout the UK and overseas.

FREE SHIPPING

MONEY BACK GUARANTEE

ONLINE SUPPORT

Dedicated Service

Free returns

International shipping

Energy Monitoring Portal