Fuse Wire

Shop for electrical essentials online now at Cromwell.co.uk. We stock a carefully selected range of fuse wires in convenient assorted packs for electrical repairs. Get quality performance at great prices from well-known brands, like SMJ Electrical®.

What is fuse wire?

A fuse wire is a conductive strip of metal with a low melting point. It acts as an electrical safety device, melting and stopping the flow of electricity in the case of an electrical overload, also known as an overcurrent. Excessive current passing through a conductor can lead equipment to overheat and cause irreparable damage. In extreme cases, this could lead to an electrical fire, and so the humble fuse wire is an extremely important part of any electrical device.

When are fuse wires used?

Fuse wires are used in all kinds of electrical applications. They're typically housed in a safety cartridge to allow for quick removal and replacement to a holder that connects them to the circuit. They feature in all electrical appliances, light switches, automotive electrics and anything that has a circuit conductor.

Considerations when choosing fuse wire

• Size - use the calculation of Watts / Volts = Amps + 10% to accurately find the best size fuse wire for your application.

Fuse wire jargon buster

To keep you up to date with safety regulations and British legislation, we've outlined an applicable safety standard to help when you buy fuse wires.

What does BS 646:1958+A2:2013 mean?

This legislation stipulates the manufacturing framework for Type A cartridge fuse links, including dimensions and test methods. These types of fuse links are widely used in two-wire circuits with a voltage of up to 250v maximum and are typically used in manufacturing, auto industries and telecommunications.

Let's break it down...

• BS - This denotes that the British Standards Institute produced and monitors this legislation in British law.

• 646 - This is the identifying legislation number.

• 1958 - The original standard was first published on 31st January 1958.

• A2 - This is the second amendment applied to this standard (the second overwriting the first).

• 2013 - This amendment was made in 2013.

FAQs

What kind of metal is used as a fuse wire?

Fuse wires must be made of metals with a low melting point of up to 200°C. The metals typically used for this task are:

• Lead-tin alloy - used mostly for low-current appliances.

• Copper - this is the most commonly used metal for fuse wire as can be supplied in larger diameters at low prices.

• Silver - this is the most expensive of the metals and is very effective as a fuse wire.

What's the difference between a normal wire and a fuse wire?

Unlike normal wires, fuse wires have a very low melting point. This is because, in order to protect a circuit against excessive current, the fuse wire must melt to open the circuit and prevent the current from moving through and damaging the whole system.