Ideally, one piece of long flex should be used rather than extending an existing fles. However sometimes it is difficult to replace the shorter flex with a longer flex, because it involves dismantling the appliance. In this case it may be wiser to use extensions.

Flex should never be extended by twisting the wires together and covering with insulation tape. This practice is very dangerous and could result in overheating wires or the wires being pulled out accidentally.

There are two main ways to extend flex; using a flex connector or using a detachable flex connector i.e. extension lead. For more details about extension leads / detachable flex connector see Extension leads.
 

 
Both ends of the flex you wish to join should be prepared and stripped (see Preparing flex for connection). Measure the amount of sheath to be stripped so that the outer cable will be gripped by the cable grips in the flex connector - this is important in making the connector safe.

Open up the flex connector and pass the flex thought the grip. Screw the conductors into the screw terminals, ensuring that the earth cable (green/yellow) goes into the centre terminal.

Repeat this process with the other flex, pass it through the grip and screw the conductors into the terminal block ensuring that the colours match that of the first flex, i.e. brown to brown, blue to blue, and green/yellow to green/yellow. Remember that the green/yellow conductor should be in the centre terminal. Finally tighten both flex grips and screw the cover back in place.
 

 
Electrics > Extension leads
Electrics > Preparing flex for connection
 

 
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