Ti400 shocks on charging

My TiBook 400 has started to give me a small shock when the charger is plugged in and I touch a corner.
Colin Fox wrote on :

My TiBook 400 has started to give me a small shock when the charger is plugged in and I touch a corner. The battery is only a couple of months old. Any one have a suggestion as to what may be going on?

Thanks, Colin

Ian Gregory replied on :

On 2007-03-21, Colin Fox cfoxs@redacted.invalid wrote:

My TiBook 400 has started to give me a small shock when the charger is plugged in and I touch a corner. The battery is only a couple of months old. Any one have a suggestion as to what may be going on?

I used to get a tingle from the case screws of my iBook when it was on charge, but that was because ground in my house was not really ground - it hovered at as much as 20V. I still haven't sorted it out properly.

Ian

Steve Jones replied on :

In article C227274C.1D8EE%cfoxs@redacted.invalid, Colin Fox cfoxs@redacted.invalid wrote:

My TiBook 400 has started to give me a small shock when the charger is plugged in and I touch a corner. The battery is only a couple of months old. Any one have a suggestion as to what may be going on?

Thanks, Colin

Check the cable on your AC adapter. I had one that was worn out to the point that you could see arcing inside the cable right behind the part that plugs into the computer. I don't know if that would necessarily cause what you're seeing, but if it only happens when the charger is connected, it seems possible.

Steve

David Empson replied on :

Colin Fox cfoxs@redacted.invalid wrote:

My TiBook 400 has started to give me a small shock when the charger is plugged in and I touch a corner. The battery is only a couple of months old. Any one have a suggestion as to what may be going on?

My PowerBook G4 DVI 667 has always done that, as did my iBook G3 500 before it.

From my experimentation, it seems that the power adapter has a small leakage current at high voltage, which ends up on the computer's outer metal case while the adapter is plugged in.

This results in a tingling or mild shock effect when you touch the surface while you are also in reasonable contact with ground. It isn't dangerous, but is disconcerting.

Later PowerBook models had a new design of the power adapter which seems to have fixed the problem. If I use a more modern power adapter on my PowerBook, the problem goes away.

Salmon Egg replied on :

On 3/22/07 6:01 AM, in article jones948-7B14E5.09014822032007@redacted.invalid, "Steve Jones" jones948@redacted.invalid wrote:

In article C227274C.1D8EE%cfoxs@redacted.invalid, Colin Fox cfoxs@redacted.invalid wrote:

My TiBook 400 has started to give me a small shock when the charger is plugged in and I touch a corner. The battery is only a couple of months old. Any one have a suggestion as to what may be going on?

Thanks, Colin

Check the cable on your AC adapter. I had one that was worn out to the point that you could see arcing inside the cable right behind the part that plugs into the computer. I don't know if that would necessarily cause what you're seeing, but if it only happens when the charger is connected, it seems possible.

Steve I would want to know more about the shock. How are you connected when you receive one? Can you measure excess voltage using a voltmeter? Otherwise, it could be your imagination.

Bill -- Fermez le Bush--about two years to go.

Wayne C. Morris replied on :

In article C2282F8B.6ADB7%salmonegg@redacted.invalid, Salmon Egg salmonegg@redacted.invalid wrote:

On 3/22/07 6:01 AM, in article jones948-7B14E5.09014822032007@redacted.invalid, "Steve Jones" jones948@redacted.invalid wrote:

In article C227274C.1D8EE%cfoxs@redacted.invalid, Colin Fox cfoxs@redacted.invalid wrote:

My TiBook 400 has started to give me a small shock when the charger is plugged in and I touch a corner. The battery is only a couple of months old. Any one have a suggestion as to what may be going on?

Thanks, Colin

Check the cable on your AC adapter. I had one that was worn out to the point that you could see arcing inside the cable right behind the part that plugs into the computer. I don't know if that would necessarily cause what you're seeing, but if it only happens when the charger is connected, it seems possible.

Steve I would want to know more about the shock. How are you connected when you receive one? Can you measure excess voltage using a voltmeter? Otherwise, it could be your imagination.

Or it could just be a static shock. You build up a static charge by walking across the carpet, or shifting around in your chair. The power cord grounds the computer, so when you touch it, your static is discharged and you feel a small shock.

Next time it happens, freeze. Take your finger off the computer and stand/sit perfectly still for a minute. Then touch it again. If you get a second shock, it's probably electrical; if you don't, it was probably static.

zit replied on :

On Mar 23, 3:23 am, demp...@redacted.invalid (David Empson) wrote:

Later PowerBook models had a new design of the power adapter which seems to have fixed the problem. If I use a more modern power adapter on my PowerBook, the problem goes away.

PowerBooks are not normally grounded. Once the insulating paint comes off, they are not double insulated either.

Any line/mains powered device attached to the Mac can produce an annoying shock, not just the Mac's own power supply. A USB printer for example.

An easy fix is to connect the headphone jack to a grounded stereo. Sounds good too :)

I'm curious about the more modern power adaptor. Did they ground the "tip" conductor of the "stereo phone jack" that they used? That would need a 3 prong power cord as well.