Laptop Power supply wiring help

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webup

505 posts

Ultimate Geek

# 41902 24-Sep-2009 20:09

Hi

Anyone good with wiring?

This toshiba power supply from an older laptop has a dodgy wire that is preventing power reaching the laptop.
I went around all sorts of electrical places and due to its specs and connector most reckon I wont be able to get a replacement or if I can it will be very expensive.

The problem is near where the wire goes into the adapter and over time it has been bent back and forwards and damaged the cable.

My question is...see there is a red wire which seems kinked in and also the black wire which once it comes out of the adapter becomes the wrap around mesh wire over top of the red cable, its not a full seperate wire as such.

What is this black one?
Does it need to be stitched back up as well or can I just repair the red wire?

bjhoogs

183 posts

Master Geek

# 258193 24-Sep-2009 22:36

The red will be positive and the black negative. Both will need to be connected (to complete the circuit), however the black wire will probably not need to be wrapped around the red. I would strip the black insulation away from where it is wrapped around the red wire, then roll the black wire together into a round shape and solder it to the other bit (using an extra piece of wire to make the red and black wires the same length if necessary). Then cover the cables with a bit of heat shrink or insulation tape (or paint on insulation tape from mitre 10 will do a tidier job).

lxsw20

2288 posts

Uber Geek

Subscriber

# 258209 24-Sep-2009 23:16

Cut the cable at a point where its not broken like that, resolder them onto the board, discharge the caps first.

Don't know what your doing? Why are you taking apart a 230VAC device then :S

Tried laptopbattery.co.nz for a replacement?

boredwild

20 posts

Geek

# 258260 25-Sep-2009 09:16

This is an easy repair, but not if you don't have the skills/tools. Any local TV repair shop would fix this in a jif, and it supports the local economy. Don't like that idea? Chances are someone's selling one on ebay - just search for the part number.

webup

505 posts

Ultimate Geek

# 258302 25-Sep-2009 12:09

Well Im still alive, all fixed.

I cut the red before the damaged section and removed that 1cm.
twisted the two red ends together and elec taped it.
Then tangled together the black wire mesh and taped that.

All seems to be fine again.
Laptop now usuable again.

Its a 2.8ghz laptop that needs a big hungry power adapter.

Bung

2897 posts

Uber Geek

# 258321 25-Sep-2009 13:00

Its a 2.8ghz laptop that needs a big hungry power adapter.

If it's carrying reasonable current and especially if your twisted connection doesn't have strain relief it will fail. If you can get some solder even a BIC lighter will do as a heat source.

boredwild

20 posts

Geek

# 258326 25-Sep-2009 13:28

It's a fire hazard - being repaired this way - as that twisted connection will be subject to heating. It's your risk to take, but you may not realise that you're taking the risk for your family/flatmates as well...

AndrewTD

292 posts

Ultimate Geek

Trusted

Lifetime subscriber

# 258329 25-Sep-2009 13:38

+1 re boredwild's response.
Power supplies are not the sort of thing that we should take risks with. Especially when other innocent parties inevitably end up being exposed to the risk. If you fiddle with a power supply and electrocute yourself, (leaving aside for now the costs we would all end up paying by way of the public services such as ambulance, hospital staff etc)then that's OK. It's not OK if some visiting person gets electrocuted because of your choices. (Just my personal philosophy here.)
I really do recommend that you either buy a new one, or get it professionally repaired.
There are plenty of other things in this world for us geeks to play with / save money on.

kind regards Andrew TD