Anti-static wrist bands...

Lorddalron

Lorddalron

Lorddalron

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How good can a cheap one be? I brought one a few weeks ago just to have and i will probably use it next week when upgrading my servers RAM.

However, i thought it would have come in useful a few weeks back when i was lifting my daughter off of the trampoline. Every time i go to lift her off she gets a shock and although she loves the trampoline she gets scared now every time somebody goes to lift her off. Shes only 2 and a half. I though my brainwave of using the anti-static wrist band may of worked but she still got the shock.

Its got me wondering now whether or not to be extra vigilant when opening up my server or PC in the future.
 
You did remember to earth it?
TBH, just test for continuity between the croc clip/plug and the plate that touches your skin. Any old multimeter will do that.

More worrying, it may be the sign of a bad/non existant earth in your wiring!
 
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What are you earthing the wrist band too? I'm guessing a radiator.

Bear in mind, it's only usual to earth bond radiators when they are fed by metal pipe work, I don't just mean what you can see either, I mean under the floor, if your central heating system is using all metal pipe work then the whole system should be connected to your main earthling terminal via supplementary bonding (basically, it's earthed) ...however if your central heating system uses plastic pipe work, then your radiators won't be earthed, as they are considered to be electrically isolated, so unless they are in a position where they could possibly become live under some sort of fault, they won't be earthed. Thus using your wrist band on a none earthed unit ...is pointless, I know you wouldn't necessarily know this, hence me telling you. Make sure that you are actually earthed.

A safer bet, is using one of those plugs that you can connect an earth strap from your wrist band too, so basically you plug it in and it will earth you. If you were doing this, or you are sure that you were connecting to something that is or should be earthed, then I'd be a bit concerned about checking that out. I would suspect the wrist band to be faulty first though.
 
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Like I said, check for continuity between crocodile clip/plug and the plate where it touches your skin. If you've got a good connection between the two you've got a bigger problem.

My advice is to connect to your PC case with the PSU plugged IN but switched OFF. The neutral feed is disconnected (no chance of shock) but the earth is still there. If you unplug the PSU you unplug the earth.
 
I was just going for a guess at what might be going on, thought I would explain it to him, just incase he isn't actually earthed, even when he thinks he is. I wouldn't necessarily expect everyone to know what testing for continuity means though let alone how to do it. I will explain, just incase.

Basically you are making sure that the circuit is complete, i.e. that current can flow through it, thus it is electrically continuous.

So test between the plate and the croc clip as SlugForAButt said, you'll want to use the ohms setting on your multimeter, that's this Ω symbol, if it's not auto-ranging (if it's cheap, it most surely won't be) choose a high setting and come down until you get a reading. I do believe many/most/all of these devices have current limiting resistors in the range of 1M ohm in them, thus I would expect an end to end resistance reading oh about 1M ohm, however not knowing for sure what sort of resistor is fitted it could be anything up to a few M ohms, even a cheap sub 10 quid multimeter should have a high enough reading for this, probably 20M Ω or so, in other words you'll probably only need the highest setting and won't need to step them down.

I would say that if you get a constant reading, in the low M ohms range then it's ok, if not, assuming you performed the test correctly, the circuit is broken and that's why you are not earthed. A reading of 0 or an infinity symbol ∞ means it's not right. A very, very high M ohm reading, say more than 6M ohms could also indicate a problem. If there isn't a current limiting resistor then your reading would be much, much lower, far, far less than 1M ohm ...but still not 0 when set to the lowest ohm reading.

I hope you understood all that.
 
Lorddalron said:
How good can a cheap one be? I brought one a few weeks ago just to have and i will probably use it next week when upgrading my servers RAM.

However, i thought it would have come in useful a few weeks back when i was lifting my daughter off of the trampoline. Every time i go to lift her off she gets a shock and although she loves the trampoline she gets scared now every time somebody goes to lift her off. Shes only 2 and a half. I though my brainwave of using the anti-static wrist band may of worked but she still got the shock.

Its got me wondering now whether or not to be extra vigilant when opening up my server or PC in the future.
Click to expand...

Someone hasn't seen my sig. I thought I was changing the forums, you must have slipped through the net haha.
 
Buchanan0204 said:
Someone hasn't seen my sig. I thought I was changing the forums, you must have slipped through the net haha.
Click to expand...

:D Didn't even notice. Not about the word but what i wrote. Good sig though!!

SlugForAButt said:
You did remember to earth it?
TBH, just test for continuity between the croc clip/plug and the plate that touches your skin. Any old multimeter will do that.
Click to expand...

Unfortunately i don't have a multimeter. The strap in question is the one pictured below (Very basic). Is it not just a case of putting on the strap and attaching the crocodile clip to the chassis?

zt91.jpg


Moeks said:
What are you earthing the wrist band too? I'm guessing a radiator.

Bear in mind, it's only usual to earth bond radiators when they are fed by metal pipe work, I don't just mean what you can see either, I mean under the floor, if your central heating system is using all metal pipe work then the whole system should be connected to your main earthling terminal via supplementary bonding (basically, it's earthed) ...however if your central heating system uses plastic pipe work, then your radiators won't be earthed, as they are considered to be electrically isolated, so unless they are in a position where they could possibly become live under some sort of fault, they won't be earthed. Thus using your wrist band on a none earthed unit ...is pointless, I know you wouldn't necessarily know this, hence me telling you. Make sure that you are actually earthed.

A safer bet, is using one of those plugs that you can connect an earth strap from your wrist band too, so basically you plug it in and it will earth you. If you were doing this, or you are sure that you were connecting to something that is or should be earthed, then I'd be a bit concerned about checking that out. I would suspect the wrist band to be faulty first though.
Click to expand...

Ive had a few vods tonight so i'll come back to this one in the morning :rolleyes: :D

Much appreciated though.
 
Lorddalron said:
:D Didn't even notice. Not about the word but what i wrote. Good sig though!!



Unfortunately i don't have a multimeter. The strap in question is the one pictured below (Very basic). Is it not just a case of putting on the strap and attaching the crocodile clip to the chassis?
Click to expand...

Afraid not. PSU has to be installed into chassis and then that has to be connected to the socket on the wall. Switch off of course.

A case sitting on the worktop isn't grounded to anything. A mistake everyone makes, including my old college lecturer!
 
Buchanan0204 said:
Afraid not. PSU has to be installed into chassis and then that has to be connected to the socket on the wall. Switch off of course.

A case sitting on the worktop isn't grounded to anything. A mistake everyone makes, including my old college lecturer!
Click to expand...

Figures really.

So when i go to open up my server in the coming week, leave it plugged in, switched off at the back of the machine and attach the clip to the chassis and i should be ok.

Must pick up a cheap multimeter too.

O yea, and if its taking my daughter off of the trambopoline, run and extension lead outside, plug in the PC, switch off at the back and attach Jimmy Nails crocodile shoe to the chassis?? :D (Must go to bed :o)
 
Hehe, that's your problem then, if you were connecting to a computer chassis that wasn't plugged in, it wont be earthed. As already said, plugged in but switched off will do it.

Just remember, any metal object you earth yourself to, actually has to have a line to earth, or it's not going to do anything. Be that a computer chassis or a radiator.
 
If you're worried about it, buy an earth bonding plug (I think it's called).
It's a plug that has between 1 and 3 terminals for hooking earthing equipment to :)

I picked one up a couple of years back after finally getting fed up of having to run an earth cable to a radiator from by AS mat, now I just hook the mat and straps up to it :)
 
The anti static band didn't work for the trampoline because it wasn't you that needed to wear it.

When she bounces up and down she's generating charge which is then discharged into you when you touch her. The only way to stop this would be to make her wear the band, so she's grounded the whole time she's bouncing and unable to hold the charge she generates. Not sure if she'd be up for wearing it whilst she's playing, I guess it depends how much she hates the static shock at the end.
 
jimbob27 said:
The anti static band didn't work for the trampoline because it wasn't you that needed to wear it.

When she bounces up and down she's generating charge which is then discharged into you when you touch her. The only way to stop this would be to make her wear the band, so she's grounded the whole time she's bouncing and unable to hold the charge she generates. Not sure if she'd be up for wearing it whilst she's playing, I guess it depends how much she hates the static shock at the end.
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This ^

If the trampolines in the garden then just attach it to a simple metal peg in the ground or the like will do it. Or even holding the crocodile clip end yourself.
 
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