No announcement yet.

Static Electricity Destruction???

  • Filter
  • Time
  • Show
Clear All
new posts

  • Static Electricity Destruction???

    I have a Ridgid shop vac and a Ridgid 5" orbital sander. I have had the sander for just over 2 years and frequently hook it up to my shop vac to keep the dust down. Just a couple of days ago I was doing this and my sander suddenly stopped. It didn't make any noises or have any burning smell, it just quit like someone unplugged it. The light on the plug was still on, so I know there was power to the sander. I removed the cover of the sander and tried to check for electricity with a little meter and couldn't find anything. I took it back to HD and got a new one 2 days ago. Last night I was sanding again and the new one did the exact same thing, it just turned off. I have noticed that my shop vac has been making unusually high amounts of static electricity and I was wondering, could the static electricity be shorting out my sander? While sanding I was continually being shocked. I have heard that there is usually more static electricity in the winter, and I live in Utah where there is zero humidity, do you think its possible? I want to fix the problem instead of continually returning to the store for new sanders. Any ideas?

  • #2
    Re: Static Electricity Destruction???

    In a word: YES!

    I'm in NY's Southern Tier, where the humidity swings are ridiculous; 90+ in the summer and 30 in the winter. Bring a new board into the shop in the winter and if it isn't stored correctly, it will cup within a couple of days. Humidity is always a challenge.

    I too have noticed some static electricity build-up on my vac hose, especially the smaller unit. The sawdust on the outside of the nozzle looks like an old highschool science experiment with a magnet and iron filings. It hasn't built up to the point where I've received any shocks though and apparently your situation is much more severe.

    Bottom line, cold air does not hold moisture... the lower the temperature, the less moisture there is in the air. So with the winter that we have just had, it's going to be a problem. Now, move that dry air rapidly over a non-conductive plastic, and it's very much like rubbing a silk cloth on a glass rod (again, from high school science)... you get electricity!

    Actually it can build to quite a potential, as is evidenced by the "shocks" that you were receiving. A few weeks ago, there was a rather irate poster who was doing a real tirade on Ridgid and their vacs; but, it isn't Ridgid at all, it's just the nature of things.

    Such static buildup can be very damaging to electronic components and is referred to as ESD, (Electro Static Discharge). Several years ago I wrote an advertising piece for a local packaging company that had a product in which to ship electronic components. At the time of my research for the piece, I recall reading that as much as 30% of solid-state components were damaged in shipment, because of ESD. While it is difficult prevent ESD, the idea is to dissipate such discharge over and around the outside of the package, container, or housing and not have it penetrate to the circuit components.

    I really don't know how to prevent this on a tool, without having an electrical shield of some type to dissipate and drain off any static charge. I know that dust collection systems recommend the use of a ground wire, that wraps or runs the length of any PVC or other plastic duct work. Perhaps, doing the same on a vac hose, right next to connection to the sander may do the trick also. The object is to drain off static before it builds up and causes a shock to either you or the sander's circuit board.

    Electronic/radio/computer techs use a wrist strap that is grounded. I imagine that a similar method would remedy the problem. While I'm not surprised by any absense of shielding, a tool manufacturer would have to use a housing material or internal shield that would dissipate static to ground, before it reaches any potential.

    I hope this helps,