Rewire 2 pin shaver plug (possibly New Zealand?) (Ed.)

[Rbods]

Wanting to change the 2 pin plug on an electric toothbrush charger to a standard 3 pin (NZ in this case). Have done this before successfully, brown and blue cables to live and neutral. However, the twin cable on this one has grey and white sleeves inside. Which is live??? Wired it with white to neutral / grey live but it tripped the fuse.

 

[Wayners]

Test.
Cut plug off.
Buy a £5 multi meter tester as this would tell you which wire goes to which pin when you cut the plug off. It's called a continuity test. If two points are joined you get a beep from the multi tester.

 

[JohnD]

Show us some photos of the things you are working with.

Especially the original plug.

 

[FrodoOne]

Wanting to change the 2 pin plug on an electric toothbrush charger to a standard 3 pin (NZ in this case). Have done this before successfully, brown and blue cables to live and neutral. However, the twin cable on this one has grey and white sleeves inside. Which is live??? Wired it with white to neutral / grey live but it tripped the fuse.

If this is a 2-pin UK "Shaver Plug", the device to which it is connected is double-insulated and does not have an Earth connection.

It is a Power-Supply in which the output is isolated from the Mains.
The "output" if this Power-Supply is fed to an induction coil in the Base for the toothbrush.

Because of all of the above, it really shouldn't matter which of the two wires you connect to the Line and which to the Neutral
and connecting them the "wrong way round" should not cause an overload - in any case.

If when you wired it as you indicated an overload occurred, there is something else wrong.

If the wires concerned are stranded (as they will be), it is possible that an errant strand has formed a short-circuit in the plug.

 

[bernardgreen]

it is possible that the plug contains a power supply module and the grey and white sleeves from the plug are not mains voltage

 

[JohnD]

Quite right. If only there was some way we could know.

Show us some photos of the things you are working with.

Especially the original plug.

@Rbods has not been back to answer any of us.

 

[Rbods]

Hi everyone and thanks for the replies! I’m going to get my daughter to send me some photos - she’s in NZ and I’m in UK so will post them when she finally gets them to me.

 

[FrodoOne]

I’m going to get my daughter to send me some photos - she’s in NZ and I’m in UK so will post them when she finally gets them to me.

In that case,
who changed the plug - where and when?

 

[Rbods]

My daughter in Nz, last week. It was her U.K. oral b pro 3 that she took with her. As I say, she’d already changed the one on her sisters (slightly older model oral b) which was a simple twin brown and blue cable, no issues.

 

[Ragnar_AT]

All the pictures of that model I can find online seem to show various regular mains plugs (UK shaver, Euro, US).

 

[Rbods]

It ‘had’ a U.K. shaver style 2 pin plug.

 

[Ragnar_AT]

It ‘had’ a U.K. shaver style 2 pin plug.

The main question was whether that was just a plug (seems most likely now) or a small-ish power supply. If it happened to be the latter, fitting a mains plug to the cable would result in a fairly spectacular meltdown. Electronics designed for something like 5 or 12 V DC don't take kindly to being fed 230 V AC. My own toothbrush charger has a USB A plug on it and came with a small power supply so I'd say until we see pictures of the original plug it's still a possibility that there was a power supply.