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Screw driver accidentally touched ground wire while screwing a hot black wire in the light switch box. The power went out but the circuit breaker did not trip. Can you tell me how to fix it?
Wiki User
∙ 15y ago
If you didn't burn the wire off then the breaker did trip. Sometimes a tripped breaker is hard to see. Go down the whole panel switching each individual breaker off and then on again. This should rectify the problem. A word from the wise, I have been an electrician for 42 years and always shut the power off before working on equipment.
Wiki User
∙ 15y ago
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Why does not tester light up when it is touched to neutral of 3 pin socket?
Because the neutral is simply the return path in a complete circuit. It doesn't carry any power - that's only found in the live wire.
What did Luigi galvani discover?
He discovered that frogs legs convulsed when touched by metal that was charged by electricity.
Should the ground and neutral wires be wired together?
The answer to that question depends on exactly where in the building's wiring is being asked about.The only place the neutral and ground (or "earth") wires in a building should ever be tied (or "connected") together is at the incoming service main breaker panel "upstream" of all the fuses and/or circuit breakers which are there to protect the hot (or "live") wires for the various circuits installed in the building.In the absence of an earth wire (= ground wire in US/Canadian English), if the appliance suffered some damage that caused a short circuit between the high voltage "hot" lead and the case of the appliance, the damage would make the case live and it would cause an electrical shock to anyone who touched it.If the case is earthed by using a ground wire (= earth wire in British English), if that same damage occurred the hot lead would immediately be shorted to ground and in theory cause the fuse to blow or circuit breaker to open, thus eliminating the danger of a live case.In the USA I think we refer to what you are calling an "earth wire," as a GROUNDING CONDUCTOR, which in effect is a separate conductor which seems to be doing nothing but is in fact a protective wire. It is there, ready to take the current away to earth if it, or the body/frame of the electrical device it is connected-to, makes contact with any "hot" wire. [120 Volts mains power is carried in two current carrying conductors "hot" and "neutral".]So, IF one of the "hot" conductors should contact the metal frame or housing - perhaps because the appliance got damaged by being dropped from a table, or similar accident - the third wire which is the "ground" or "earth" wire, which runs directly from the housing to the grounding [or earth bus] in the fuse or breaker panel, will in effect cause a short circuit which should blow the fuse or trip the breaker.This third wire also guarantees a current path back to the load center where the fuse or circuit breaker protecting that circuit is located, in the event the hot wire should be in contact with the frame, but the other [neutral/return] conductor should happen to be cut, disconnected, or open.The idea is to guarantee that if a part of the device should become "hot," which could be fatal to anyone who then came into contact with it, would trip/open the circuit protection device [fuse or breaker], turning off the flow of current to that circuit.All the neutral and ground (or "earth") wires in a building are tied or linked together at the incoming service main breaker panel. This is the only place they should ever be tied together because it is "upstream" of all the fuses and/or circuit breakers protecting the hot (or "live") wires for the various circuits installed in the building.Warning: we must never assume that a neutral is safe to touch: it has to be checked with a voltmeter or a voltage indicator to be sure it is not "live". This is because a neutral wire is designed to carry current under normal circumstances.So, if a neutral wire going back to the incoming main breaker panel has not been properly connected - or suffers a deliberate disconnection or some accidental damage which causes it to break - then it and any neutral wires connected to it further downstream will go live up to the break because of being connected to the downstream loads which still have hot feeds coming into them!That is why we should never use a neutral as a substitute for a proper, separate, ground or "earth" wire.In addition to the above description it should also be mentioned that the presence of an earth wire allows a very sensitive safety device called a Ground Fault Circuit Interrupter (GFCI) to operate. It will cut off the power supply to the appliance even if a tiny current of a few thousandths of an Amp is detected flowing in the earth wire, which should normally carry no current at all.In USA/Canada, and similar countries which use mains supplies running at 120 Volts 60 Hz to feed power sockets, it is probable that the latest designs of GFCIs which are fitted to all new wiring work actually operate in the same way as the RCDs described in the next paragraph, although they are still commonly called GFCIs.In Europe, where 230 Volts, 50Hz mains supplies are standard in homes, offices, etc. such protective "trip" devices are called Residual Current Detectors (RCDs) because, in addition to being able to detect small earth leakage currents, they have the ability to detect very small differences between the currents flowing in the hot (or live) wire and the neutral wire. Such imbalances might be caused by minor damage to the appliance which allows a small current - known as a residual current - to leak to earth either via the user or via the earth wire (if one is connected) even though the appliance itself is still working. So using an RCD helps to prevent a serious shock hazard to users if ever the kind of minor damage occurs which, in the absence of an RCD, would cause the appliance's casing to become "hot" or live.Thus RCDs give a very high level of safe operation even if no circuit breaker has tripped and no fuse has blown and the appliance appears to be working normally. (But it has really become unsafe!) Because of the enhanced protection they give to users of appliances the latest European wiring regulations (= wiring codes in US/Canada and elsewhere) make it compulsory to fit RCDs to all new power circuits.As always, if you are in doubt about what to do, the best advice anyone should give you is to call a licensed electrician to advise what work is needed.Before you do any work yourself,on electrical circuits, equipment or appliances,always use a test meter to ensure the circuit is, in fact, de-energized.IF YOU ARE NOT ALREADY SURE YOU CAN DO THIS JOBSAFELY AND COMPETENTLYREFER THIS WORK TO QUALIFIED PROFESSIONALS.
How does an electric cell work?
The first electrical circuit was created by an Italian physicist named Luigi Galvani in the 1780s. He discovered a frog's leg would twitch when touched with two pieces of metal. His work was taken up by Professor Alessandro Volta. He created the Vollaic pile. The pile consisted of discs of zinc and copper with pieces of cardboard soaked in brine between the metal plates. It was the first "wet cell battery". This principle is used similarly today but the metals and fluids are quite different.
How electric tester works?
There are many types of electric testers in use. One kind is a two contacts tester where there will be two connecting leads and one or more neon lamps to indicated the presence and approximate magnitude of test voltage. Here one contact is placed on the wire to be tested and the other lead is placed on the reference level like ground or other circuit parts. Another kind is a one contact tester which usually is in the form of a screw driver. The end portion is placed in contact with the wire to be tested and the back of the tester is touched by a body part. A neon lamp inside the transparent tester body will glow if the wire is live. The lamp needs only very little electric current to glow that, it uses the capacitance and resistance of the human body to complete the circuit by making a current flow to the ground.
Why tap in your house gives shock when it is touched or used?
Your water system is not grounded. Turn the main breaker in your distribution panel to off and ground the water system. If a "hot" wire has come into contact with the plumbing, when you turn the electrical panel main breaker back on a breaker will trip. This will give you the circuit that is at fault and a place to start looking for the short circuit.
Is a ground fault circuit breaker nessesary for a washing machine?
A ground fault circuit breaker essentially senses the difference currents flowing in the incomming & return wire of an electrical supply circuit. In normal cases ideally the difference must be zero or very close to it. Whenever there is a fault & the electrical path also takes any other route e.g a operator who has accidentaly touched any live part of the equipment, there is a current flow imbalance in the input & return path of the electrical supply circuit. This imbalance is sensed & used to trip the main electrical circuit & thereby limits the Intensity & Duration of the Electrical current flowing through the operator. This results in the operator feeing a small jolt instead of a nasty or hazardous electrical shock. From the above it is obvious that ground fault circuit breaker is essential for safety of the operator especially where the applicance is working with water or in watery surroundings & there is every chance of the water or operator accidentally comming into contact with a live electrical circuit & thereby create a safety.
Why have I always been told not to load up an electrical circuit or equipment more than 80 percent and where is this stated?
The 80% ideal is from the NEC. Let's say you have a standard 15A circuit. This circuit is rated to carry a maximum of 15A, no more. If you try to draw more than 15A, the breaker will pop. Now, you can put 15A worth of appliances on this circuit, but then you are running it at its maximum all the time. If you add anything else to this circuit, you will pop the breaker. If you have something that draws surge current, it can opo the breaker under normal use. You have no "wiggle room" when you load it at its maximum. Also, as touched on above, if you run your circuit at the maximum you cannot add anything else. This is generally a sign that you need to upgrade your wiring. Furthermore, the breaker can handle 15A indefinitly under standard test conditions, which are close to ideal. Your breaker box may not be ideal. Breakers are thermal devices, so self heating and heating from other breakers can be a problem. If your breaker is hot, it will pop sooner than if it is cold. The more current that flows through it, the hotter it will get. If you are overloading circuits the easiest thing to do is to break the circuit up into multiple circuits. The exact implementation will depend on the situation.
How far should exterior electrical wires be from windows?
Far enough away that no one can accidentally reach them from the window. Electrical transmission wires should never be touched, but they need to be brought in to a fuse or breaker box, usually in the basement for single dwellings or some closet for apartments.
If you accidentally touched cocaine will it be in my hair?
if you wash your hands as soon after it should not show up in your system at all
What would be the cause and solution of partial electricity going out if wires may have touched when fixing a closet switch?
Blown fuse or tripped breaker. Replace the fuse or reset the breaker.
When live neutral wires in a domestic circui t come in contact with each other what occurs?
If the live and neutral wires come into contact the circuit is completed and a current will flow. Since there is no appliance in the circuit and the resistance in the wires is low the current will rapidly rise to high levels. Typically a safety device, a fuse or circuit breaker, will then react and stop the current flowing. The reaction speed of the safety devices is normally not quick enough to prevent a shower of sparks (molten metal) and melt damage to the wires where they touched.
How does short circuit occur?
short circuit occurs when two wire which consist of one live and neutral wire are in contact with the main and the other end of the wire are touched each other short circuit occurs
Who were the five Americans who accidentally touched Queen Elizabeth I?
America was not a country at the time when Queen Elizabeth I was alive (b 1533-d 1603)
If you accidentally spill bleach and your baby touched it with his hand can it harm him?
As long as the baby did not put their hand in their mouth, it is fine. You should wash your babies hand as soon as you can.
What should the ohmmeter read when the lead probes are touched together?
When the lead probes of an ohmmeter are touched together, the ohmmeter should read close to zero ohms, indicating a short circuit or very low resistance between the probes.
You accidentally touched your friends boob what do you do?
this happend to me once. my hand slipped into her bikini top at the pool. she smiled at me then started to make out with me. then we had sex. try it. P.S. im serious. this happend.
