Dangerous Fuse Modification

A plain three amp fuse with a dangerous addition

Bought from well-known online retailer, a mains (240v) to 12v transformer (for running car cigarette lighter accessories) contained the modified fuse shown above.

If I buy anything electrical online I always check the plug, just in case there is a fake fuse inside. However this was a new experience for me, the fuse has been modified with the addition of a soldered-on insulated wire. This will drastically raise the rating of the fuse and is both dangerous and illegal.

It says 3 amp fuse on the label and inside is a 3 amp fuse but …


Substandard IEC Lead

This IEC lead was purchased on a well-known internet auction site and fails on several points. The plug is the main worry: it is too narrow giving little protection against fingers contacting the (unsleeved!) pins, it has no provision for a fuse and the pins are formed from sheet brass. These features are all covered by BS1363 which defines the construction of a genuine 13 amp plug. Under test the lead has a barely-sufficient earth bond (0.09 ohms) which suggests poor construction and/or materials.

Substandard IEC lead.
Substandard IEC lead.
Failed plug
Close-up of the plug – see above for its failings.

Counterfeit 13 amp fuses

These are turning up in goods bought on-line and elsewhere. I recently ordered a replacement power supply/charger for my laptop and when I checked the plug’s fuse, was surprised to find a 13 amp fuse (5 amp is recommended) which, on closer inspection, turned out to be a fake. Tell-tale signs are its light weight and the protruding wire under the end-cap. A genuine fuse should weigh about 2.3 grams, my fake weighed about 1.6 grams.
Counterfeit 13amp Fuse, would a PAT Tester find this?

Fake fuse
A counterfeit fuse – note the fuse-wire visible under the left-hand cap.

Not only illegal but dangerous – these fuses have no sand filler in the cartridge. The sand is essential in preventing an explosion if the fuse blows. Fake fuses have been known to blow the top off the plug exposing live terminals. More from the DTI.