Is it static discharge or a 60Hz thing? If it's static discharge, it'll be a a very short jolt followed by nothing. In which case you can ground your body, like to a water pipe or something earth grounded, before touching it an you'll be fine.
If the shock is a steady tingling, it's likely a 60Hz line voltage thing and it means your equipment isn't properly grounded. This can happen if a "hot" wire is touching the metal frame or enclosure of an appliance, like your equipment, and the frame isn't grounded. Ideally, any equipment with a metal enclosure should have that enclosure connected to earth ground, usually by the third prong of the power plug.
I would get an ohm meter and measure the resistance between the third prong of the power plug and the frame/enclosure. It should be close to zero ohms. If it's not, make it so. Also check inside the equipment and make sure no hot wires(like that partially exposed wire) are accidentally touching the frame.
In a three pronged power plug, one prong will be hot, the second ground, and the third is an extra safety path to ground. You can also use an ohmmeter to measure the resistance from the hot prong to the metal case of your equipment. Also make sure do this with the equipment unplugged :-)
If you live in an old house and keep receiving shocks when you turn on the lights, check the outlets. If they have only two holes, you probably have outdated circuitry that isn't grounded. If you live in a house with updated, grounded circuitry and you still get shocks, however, the problem may be a buildup of static electricity from the carpeting. In both cases, the electricity uses you as a path to ground.
Before the electric code began to require grounding in all newly installed residential circuitry, houses were wired with two-strand electrical cable with a hot and neutral wire. In this kind of wiring, even a small failure of the wire insulation can expose a person to electric shock. It happens because the person's body completes a circuit between the exposed wiring and the earth. Wearing rubber-soled shoes in the house can reduce the risk of this kind of shock, but a safer solution is to upgrade the wiring.
Ground Faults
Even if your house has code-approved grounded wiring, you still can get a shock by touching exposed wires or metal that is in contact with them. This rarely happens intentionally. It is more likely to be the result of handling a poorly insulated appliance, or one with a loose internal connection, under conditions that give electricity a path to ground through your body. To prevent this, avoid using old appliances, especially those with loose connections, and install ground fault interrupting (GFI) outlets in the bathroom, kitchen, outdoors and any location where wet conditions increase the risk of unintentional grounding.
Even if your house has code-approved grounded wiring, you still can get a shock by touching exposed wires or metal that is in contact with them. This rarely happens intentionally. It is more likely to be the result of handling a poorly insulated appliance, or one with a loose internal connection, under conditions that give electricity a path to ground through your body. To prevent this, avoid using old appliances, especially those with loose connections, and install ground fault interrupting (GFI) outlets in the bathroom, kitchen, outdoors and any location where wet conditions increase the risk of unintentional grounding.
If your house has carpeting, it is almost impossible to avoid static shocks, particularly on dry days. The movement of your feet on the carpet creates a buildup of static electricity as electrons from the carpet move from the carpet into your body and electrically energize it. When you touch any metal surface, like a doorknob, you create a circuit that allows the electrons to flow, and you get a shock. While uncomfortable, shocks from static electricity are normal. You can reduce their severity by frequently touching metal objects to ground yourself before the buildup of electricity in your body becomes too large.
I am using a piece of equipment that uses plastics hoses to connect three metal pieces (a vacuum pump, a separation chamber, and a rotating sieve). When I touch each of these to remove material I am collecting after use, I get a small shock. What can I do to prevent this?
Also, there is a loose, partially exposed wire. What can I do about this? As far as I know, it has no function.
