Additional tech you might need to complete your install

Installing a home EV charger is something many drivers have never done before. There’s a lot of charging and electrical terminology that you may see floating about.

Don’t worry, you don’t need to be an electrical engineer to understand what’s involved in your EV charger installation. Here are three pieces of electrical equipment that might be mentioned to you (plus what they’re used for) to help you prepare for your installation.

Jump to:

• Surge protection
• ISO switch
• Mini consumer unit



What’s surge protection and why do I need it?

Surge Protection Devices (SPD) are used to protect appliances from electrical power surges. They’re designed to stop power surges from reaching sensitive equipment. They’re normally fitted in a fusebox/consumer unit at the time of installation to protect your car and charging equipment.

The installation of your charger involves installing a new circuit, so you need to decide if you want an SPD to be installed. Recently, the Wiring Regulations have been updated in the UK requiring new installations to include SPDs by default. If you decide not to have an SPD fitted, you’ll need to opt out when completing your online installation survey or by completing a separate form provided by Ohme.

What’s the risk if I don’t have an SPD installed?

Surges can occur due to events involving switching of large motors or transformers close by, or if lightning strikes electricity power lines. This could cause damage to your car or charging equipment.

Most charging equipment installed before 27th September 2022 has been without SPDs and Ohme have not been made aware of any issues occurring due to surges. However, given that SPDs are inexpensive compared to the cost of repairing/replacing equipment that could be damaged by a power surge, we recommend that SPDs are fitted.

Ohme will honour the warranty of its charging equipment, whether SPDs are fitted or not. However, in either case, we do not take responsibility for any damage to the vehicle caused by surges.

What’s an isolation switch?

An isolation switch is a piece of electrical equipment that is installed to allow our installation partner to temporarily turn off all power to the property. They’re not always required and your installation can still be carried out safely without an isolation switch. If an isolation switch is required for your installation, there may be an additional for this, but this will be communicated to you prior to the installation whilst we prepare your installation plan.

What’s a mini consumer unit?

A mini consumer unit is a piece of electrical equipment that, once installed, isolates the charger from all other appliances at the property. Your main consumer unit (also known as a fusebox) will be connected to lots of appliances including your dishwasher, washing machine, and plug sockets.

A mini consumer unit isn’t always required, but you may need one if your charger can’t be connected directly to your main consumer unit . Connecting your charger directly to your main consumer unit isn’t always possible, for example if your main consumer unit doesn’t have any spare ways (these are the individually labelled switches you will see on your consumer unit) or if your desired charger location is too far away (or hard to reach).