Author Topic: Want to Fix Anti Static Wrist Strap that I Damaged  (Read 1839 times)

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Offline Boris_yoTopic starter

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Want to Fix Anti Static Wrist Strap that I Damaged
« on: July 23, 2022, 03:12:14 pm »
Hello.


I have bought this cheap Chinese multimeter over a decade ago. Also later bought additional probes from China because people recommended them. Eventually when I lifted both, one of the probes had its cord disconnected from it. Fine. I have probes that came with original multimeter.

Today I wanted to test continuity in antistatic wrist strap because before using it, a small part of shielding came off, exposing the wire at the end. Also happened on the alligator clip's part. Little did dummy me know that it has capacitor that cheap multimeters won't be able to detect the closed loop. There was continuity between  alligator clip and exposed wire but there was no continuity between exposed wire and grounding button. I didn't know and assumed that wire got damaged within yellow casing that metal button is molded into.



Long story short the antistatic wrist strap works and shows .983 reading using 2M ohm setting on multimeter. I guess it is okay and it works properly so I can start working with electronics?

I want to fix what I damaged because I am interested in it and I happen to have a crimping tool, ferrules and red sleeves that I have recently ordered. I have sleeves that require a heat gun that I don't have but I have hair dryer and hair curler which when has it's accessory removed, blows concentrated hot air. I also have butane jet lighter.

I am wondering which route should I go to protect exposed wires from being damaged further. Can ferrules and/or red sleeves affect the conductivity to properly keep me discharged from static electricity? Does one affect more than the other? I think red sleeves are for 2.5mm sized wires and not sure if they will fit.



You can also see the solid yellow casing that I cut right before it connects to metal button. Since it still has its cut part in place I was thinking of filling the gap with a glue gun. Would it be okay or I should remove that part and go the ferrule or sleeve route? I will probably still have to apply glue between yellow casing and ferrule to prevent wire from moving?



Thanks
« Last Edit: July 23, 2022, 03:25:36 pm by Boris_yo »
 

Offline PlainName

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Re: Want to Fix Anti Static Wrist Strap that I Damaged
« Reply #1 on: July 24, 2022, 01:26:22 am »
You'd be better of just buying a replacement, but as a thought experiment...

The ferrules and crimp aren't going to work because:

1. No way to skip them on without cutting the wire.

2. Once on, there is nothing to stop them breaking the wire through leverage since they aren't fixed to the yellow casing.

You might have success if you can get epoxy to fix to the yellow housing. If it did then you could cut some reasonably rigid tube to allow you to wrap it around the wire, then use the heatshrink to close it up and protect it. Epoxy the button end so that tube won't move relative to the case, and a little in the other end to lock the cable sheath into it. It will be a horrible mess, though.
 
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Offline Boris_yoTopic starter

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Re: Want to Fix Anti Static Wrist Strap that I Damaged
« Reply #2 on: July 24, 2022, 05:57:54 am »
You might have success if you can get epoxy to fix to the yellow housing. If it did then you could cut some reasonably rigid tube to allow you to wrap it around the wire, then use the heatshrink to close it up and protect it. Epoxy the button end so that tube won't move relative to the case, and a little in the other end to lock the cable sheath into it. It will be a horrible mess, though.

I could cut the wire, crimp with ferrule and wrap with insulation tape?
How about using glue from glue gun rather than epoxy?
 

Offline niconiconi

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Re: Want to Fix Anti Static Wrist Strap that I Damaged
« Reply #3 on: July 24, 2022, 06:23:14 am »
Little did dummy me know that it has capacitor that cheap multimeters won't be able to detect the closed loop. There was continuity between  alligator clip and exposed wire but there was no continuity between exposed wire and grounding button. I didn't know and assumed that wire got damaged within yellow casing that metal button is molded into.

Not capacitors. It has a 1 MΩ resistor, a megaohm. You should be able to measure this resistance using the highest range in resistance mode with your multimeter.

The resistor is here to increase your chance of survival when you accidentally touch mains voltage, without it there would be a direct path to ground through your body.
« Last Edit: July 24, 2022, 06:25:24 am by niconiconi »
 
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Offline PlainName

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Re: Want to Fix Anti Static Wrist Strap that I Damaged
« Reply #4 on: July 24, 2022, 11:09:41 am »
Quote
How about using glue from glue gun rather than epoxy?

I doubt if hot glue will because it's too flexible and not awfully sticky so will work itself loose. But it's easy to clean up if you try that and it doesn't work.

 

Offline Boris_yoTopic starter

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Re: Want to Fix Anti Static Wrist Strap that I Damaged
« Reply #5 on: July 27, 2022, 10:03:06 am »
The resistor is here to increase your chance of survival when you accidentally touch mains voltage, without it there would be a direct path to ground through your body.

I read how someone inserted alligator clip into receptacle's ground. I don't feel comfortable with that for some reason. But while resistor can's protect me from electrocution it can still minimize the magnitude of it?
 

Offline tooki

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Re: Want to Fix Anti Static Wrist Strap that I Damaged
« Reply #6 on: July 27, 2022, 02:08:56 pm »
Nnnnnoooo… “electrocution” by definition means death or severe injury by electric shock. If you reduce the magnitude significantly, it’s no longer deadly or severe and thus is no longer electrocution. The high value resistor does just that, so it does prevent (not just reduce) electrocution. You could touch mains electricity through a 1Mohm resistor all day long with no effects. It’d be a small fraction of a milliamp, so possibly enough to feel (as light tingling) but nowhere close to dangerous.
 

Offline Zucca

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Re: Want to Fix Anti Static Wrist Strap that I Damaged
« Reply #7 on: July 28, 2022, 12:18:11 pm »
buy a new one. do not waste time.
Can't know what you don't love. St. Augustine
Can't love what you don't know. Zucca
 
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