Fuses

[Jackya]

Hi I like to buy old things and I am unsure what fuse to use as some items don't have a plug on and no label with the wattage on. So what would happen if I put a 13amp fuse in something that only needed a 5amp or if I put a 3amp in something that needed a 13amp

 

[ricicle]

You run the risk of the flex/appliance wiring becoming damaged beyond repair in the event of an overload or short circuit and the more worrying fact that this could lead to a FIRE!!

 

[comms]

13amp in something that needs 5amp = a fault developes and the cable or accessory are likely to flame or you do the electrocution dance with the fuse not blowing.

5amp in something that requires 13amp = fuse will probably blow when accessory is turned on.

 

[Jackya]

13amp in something that needs 5amp = a fault developes and the cable or accessory are likely to flame or you do the electrocution dance with the fuse not blowing.

5amp in something that requires 13amp = fuse will probably blow when accessory is turned on.

So the best thing to do is use a low watt fuse and if it blows then try the next one up

 

[ricicle]

So the best thing to do is use a low watt fuse and if it blows then try the next one up

Not really as the correct size fuse blowing would indicate the presence of a fault.

 

[Jackya]

So if there is nothing to say what the wattage is how do I find out what fuse to use.

 

[comms]

So if there is nothing to say what the wattage is how do I find out what fuse to use.

take a look on the plug itself, you may find the fuse rating stamped on it between the pins, this is assuming the plug hasnt been changed at some point.

What it the plug connected to ?

 

[JohnD]

As a rule of thumb, a lamp just needs a 3A fuse, almost everything else will use 5A.

Only something with a large heating element (fires, kettles, toasters) will need 13A.

Even old appliances usually have a makers plate on them that should tell you something about its power requirements.

If it has old round-pin plugs, familiarise yourself with the size old old 2A, 5A and 15A plugs.

 

[kai]

Could try measuring the resistance of the appliance, with a multimeter instrument, and calculate the power rating accordingly.