Air hose....shocking!!

[Clark]

I thought I was crazy at first but the air hose in the shop is shocking me.

Not sure if it's static or a short in the wiring. It only happens to a couple of the guys in the shop. If your holding the airhose or a tool plugged into it and touch the workbench....it will shock you. Most of the time it's really light. At first I thought i had a piece of metal in my hand. Then I realized i was getting shocked. Tryed touching the bench without the airhose and it doesn't happen. Even tried unplugging everything on and attached to the bench....still get shocked. It has to be the air line.

Anybody else ever experiance anything like this? Should we ground the compressor?
Clark

 

[larry_g]

So do you have a metal shielded hose that will conduct a voltage or a plastic hose that will build static. Take a voltage measurement between the bench and ground, the hose and ground and the hose and the bench. You should find the reason. If you have a steady voltage then its a voltage/ground problem. If it is a spike then you have a static problem.

lg
no neat sig line

 

[koditten]

Most likely it is the static electricity built up by the movement of air thru the hose. The air is behaving like a liquid. You touch the hose and you are dissapating the static charge. Try grabbing the hose with plyers with plasic coated handles then touching the hose to something that is aready grounded, such as a metal work bench. This will be more common if the ambient air is dry and you have moist air moving thru the air hose.
I also find this is more common if your shoes are new, most work boots have a resistance to dissapating static electricity. I notice with my older, dirty shoes this does not happen as often. I belive the static charge is moving over you to the ground vs. thru you.

These are just my observations, you could have something entirely else going on.

 

[Hlidskjalf]

Test with your meter. Sometimes improperly grounded equipment can cause this. Maybe the compressor isn't grounded and touching the work bench (which is grounded) causes a shock.

 

[z28toz06]

I'll bet its static electricity. I had that issue with a shop vac once while sucking up blown insulation. It was so strong I thought I was hitting a wire in the wall.

 

[JMCX]

It's static electricity. This is why it is very bad practice to blow off circuit boards with shop compressed air. You're supposed to use the special canned stuff.

 

[Keep]

It's static electricity. This is why it is very bad practice to blow off circuit boards with shop compressed air. You're supposed to use the special canned stuff.

I find this hard to believe, I use a small compressor to clean all of our computers, at $10 a can there is no way I am using that to clean them all.

Where did you get this from? Wasn't by chance a supplier of canned air was it?

 

[mdbeck1]

Most likely it is the static electricity built up by the movement of air thru the hose. ... This will be more common if the ambient air is dry and you have moist air moving thru the air hose.

So would it help any if you drained the compressor???

 

[willy3486]

Its static electricity I bet. I used my air hose with a cheap sandbaster kit years ago when I redid my truck. I would be usung that and it would give me a good jolt when I was sanding parts. It got just right as far as weather conditions and I could actually see the static discharge. As far as the other post about not usung it to clean electronics I would be inclined to think it would as well. I work on computers for a living and you would be surprised at how little of a static discharge could trash a logic board or other parts. When I work on a logic board I try to always touch the metal case before even pulliing a part. Many times I even have my arm on it the whole time. And thats even with all the antistatic worktops and other tools to keep static down. One thing I do wonder is if a person could get one of these aerosol type cans you can refil with paint and then use the airline to charge it to dust with. You could fill it up and then touch the can if its metal to a ground . As far as the aerosol cans you buy, I buy in bulk to get it cheaper. And the stuff in the cans is not really air its chemicals. They use some type of chemicals that do not put water in the release of the chemicals. Plain air would also have the tendency to introduce water vapors on the item dusted. I use the air compressor to dust off some things like when I work on my car or even some electronics liike older radios and such. But the new electronic and computerized stuff I use the can stuff. I have seen too much computerized stuff get trashed due to static.

 

[TheGrooveking]

Have someone check the ground in your electrical system. The reason I say this is there is a possibility that the ground for your electrical system has come disconnected or has an intermittent termination. This will cause the ground to shift over possibly to the water pipes (in some systems they would ground to/thru the incoming water pipe, thus the whole metallic pipe network becomes somewhat energized if a piece of equipment is leaking electrically speaking. In many facilities theswater pipes are mounted to the trusses or other structural components that also have air pipes mounted to them. I know it may seem far fetched but I seen stuff like this when a floating neutral occurs.

TheGrooveking

 

[larry_g]

I find this hard to believe, I use a small compressor to clean all of our computers, at $10 a can there is no way I am using that to clean them all.

Where did you get this from? Wasn't by chance a supplier of canned air was it?

Do a search on ' electrostatic discharge ' or ESD. I spent a few years working to prevent ESD in the electronics factory I worked in. Huge problem and millions spent to reduce the problems. So far you have been lucky with your blowing.

lg
no neat sig line

 

[jpoe]

Rubber and PVC are horrible conductors, and even in a humid environment, air is a poor conductor. I am interested to see what you find out. I would hazard a "guess", and I mean that in the most liberal definition possible, that you have wiring problems.

 

[PeaceKeeper]

Do a search on ' electrostatic discharge ' or ESD. I spent a few years working to prevent ESD in the electronics factory I worked in. Huge problem and millions spent to reduce the problems. So far you have been lucky with your blowing.

lg
no neat sig line

I thought it had to with the moisture in the compressed air, the stuff in a can is dry.

You need to check it with a meter like people mentioned and make sure you don't have a wiring problem. Better safe than sorry.

 

[BillK]

Clark,
The glass bead booth at the shop will spark right through the front of my shirt and zap me in the stomach during the winter when it is dry. I am sure it is static, you must have a killer air dryer on the system.

 

[Keep]

I understand the static issue. I just have never heard that using compressed air will cause it.

The compressor is grounded, rubber hose, air is clean, I just don't see it

What am I missing?

 

[BillK]

I understand the static issue. I just have never heard that using compressed air will cause it.

The compressor is grounded, rubber hose, air is clean, I just don't see it

What am I missing?

Keep, just the air moving over the boards can cause static. I used to work for a large elecronics firm and we had ground straps for use any time we were using compressed air to clean circuit boards.

 

[Keep]

Keep, just the air moving over the boards can cause static. I used to work for a large elecronics firm and we had ground straps for use any time we were using compressed air to clean circuit boards.

Okay, so then what is the difference between air from a compressor and air from a can?

I know we are sort of getting off topic here.

 

[Charles (in GA)]

In dry weather I get a serious jolt from the bead blast cabinet. It will come from the metal housing around the edge of the glove retainer ring and get my arm, or hit my nose. Real annoying. I hard grounded the cabinet to the metal building with a ground wire an the building is grounded to the ground rod and building electric ground, but it didn't do any good.

Guess I need a static free work floor mat.

Charles

 

[JMCX]

I understand the static issue. I just have never heard that using compressed air will cause it.

The compressor is grounded, rubber hose, air is clean, I just don't see it

What am I missing?

I'm not an expert but I would say it's because the hose and soles of your shoes are rubber that the charge builds up at the end of the hose. It has to do with the velocity of the air through the hose/nozzle.

I live in a dry climate and have felt the jolts while sandblasting. My schooling was in electronics and we were told never to use compressed air for cleaning. There's lots of things you shouldn't do that can get away with 99% of the time though.

 

[Kevin54]

I'm not an expert but I would say it's because the hose and soles of your shoes are rubber that the charge builds up at the end of the hose. It has to do with the velocity of the air through the hose/nozzle.

I live in a dry climate and have felt the jolts while sandblasting. My schooling was in electronics and we were told never to use compressed air for cleaning. There's lots of things you shouldn't do that can get away with 99% of the time though.

As stupid as it sounds, I was going to suggest the same thing to the OP to change his shoes. I had a pair of shoes one time that I got shocked whenever I touched anything it seemed like. Whether walking across a room or getting in and out of the car. They are the only pair of shoes that do it.