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New Electrical Work
Electrical work ranges from the installation of new electrical components to the maintenance and repair of existing electrical infrastructure. It may also include wiring airplanes, ships and other mobile platforms.
4,938 Questions
3
What kind of wire do you use for 120 volts and what amp breaker do you use?
#12/2wground & a 20 amp breaker should be enough for lights,receptales.
How can you convert 240v to 120v for ac?
Use a step down transformer 240 primary to 120 secondary. You must know what the connected load (amps) is so that you don't overload the transformer. Small transformers are rated in VA.
How does an automatic transfer switch work?
In a nut shell. Transfer switch senses incoming voltage (power company) through a relay. When relay drops out due to lack of voltage, contacts close and start the generator. When generator gets up to speed, second relay senses the generator's voltage and opens contactor that is connected to power company's incoming voltage. When that contactor is open, its auxiliary contact closes the generator contactor. The load side of both contactors are connected together to a load (could be a house, factory, hospital, machinery) With the generator contactor now closed the generator is supplying voltage to the load. Still with me? When the incoming (power company) voltage resumes, it energizes a timer until the power is stabilized, usually about 5 minutes. The timer contacts drop the generator contactor out, dropping the load for about a 1/4 of a second and re energises the incoming voltage contactor. The generator usually stays running up to 10 minutes to cool down and it then shuts its self off. The transfer switch is then ready for the next power failure. Some nut shell.
What is IC housing for recessed lighting?
IC recessed fixtures can be covered with insulation. Since insulation can be in direct contact with the fixture housing they reduce energy loss. The old type fixtures had to have a box of non combustable material built over the fixture for fire-proofing. Recessed fixtures have come a long way.
Technically no. In the USA the NFPA electrical code requires a separate circuit for each large appliance receptacle- there are a few exceptions (such as a heater and AC on same circuit) - I don't think the welder is one of the exceptions. In practice, as long as only one receptacle is used at a time, it will work fine Make sure that the wire size is correct for the current (amp) draw. This is taken off of the welder nameplate. Size the breaker to protect the wire size. If more that one welder gets plugged in the breaker will trip.
What is a 30 amp circuit breaker used for?
A 30 amp circuit breaker is needed unless the load is a motor circuit, then it has to be sized to 250 percent of the motors full load amps.
For 30A circuit is needed breaker 30*1.25=37.5 --> 40A.
If load is lamp or heater, then use breaker of group A or B.
If load is motor, then use breaker of groupC or D (very hard start) or special safe breaker for motor - with variable amp setpoint.
See related link also.
By code you are only allowed 80% of the rating of a breaker. So 30x80%=24amps.
24 amps is the MAX allowed on a 30 amp breaker. You would need a 40amp breaker for a 30 amp circuit. 40x80%=32. So you would want a double pole 40amp breaker.
It is not working or it doesn't working?
I buy a new game called hotel giant the main menu loaded ok my hotel giant was install now it isnt working everytime I start a new game it returns back to my desktop and it say that HT Has Stopptop Working
Can you put 3-15 amp 2- 20 amp 2- 30 amp and 1-60 amp breakers on a 100 amp service?
Yes, the assumption is that when house circuitry is layed out not all appliances will be on at the same time. If for some strange reason they were all loaded up the main breaker would trip. Just keep in mind that the main purpose of all breakers is to protect the wire that is connected to it. Secondally to remove any short circuits that might occur on these wires.
A 208V water heater can te be replaced by a 240V water heater?
Yes but you will not get the full watt rating out of the tank. Watts = amps x volts. Say the tank draws 20 amps. 20A x 240V = 4800 watts. 20A x 208V = 4160 watts. It will take longer to heat your water with less wattage.
Why would an electrical relay hum?
The reason the relay humms or buzzes is that the pole faces on the relay are not aligning properly. This could be a result of the relay being out in the weather and developing a coat of rust on it. If the relay stops the noise when given a tap on its side then that is the cause. The other cause could be from a broken shorted turn. The use of laminations in an ac relay reduces the heating due to eddy currents. In addition, a copper strap or ring (called a shorted turn) is placed near the end of the pole piece of an ac relay to reduce chatter during operation. Because the ac is going through a peak, dropping to zero, going through a peak in the opposite direction, and then dropping to zero again during each complete cycle, the coil tends to release the armature each time the current drops to zero and attracts the armature each time it reaches a peak. The shorted turn acts as the secondary of a transformer, the primary of which is the relay operating coil. The current in the shorted turn is out of phase with the current of the operating coil because the copper ring has low-inductive reactance. Thus, when the operating coil flux is zero, the flux produced by the shorted coil is different from zero, and the tendency of the relay to chatter is reduced.
Should a hot water heater be put on a 30 single or 30 double amp breaker?
What governs the type of breaker is the voltage and wattage of the heater elements. If the tank is 120V then you would only use one breaker. The size of the breaker you use will depend on the watts of the element. Watts = amps x volts, Amps = Watts/ volts. Once you establish the amperage then size the wire and the breaker to fit. If the tank is 240V the same rules apply only you would use a 2 pole breaker. IF YOU ARE NOT ALREADY SURE YOU CAN DO THIS JOB
SAFELY AND COMPETENTLY
REFER THIS WORK TO QUALIFIED PROFESSIONALS. If you do this work yourself, always turn off the power at the breaker box/fuse panel BEFORE you attempt to do any work AND always use a meter or voltage indicator
to insure the circuit is, in fact, de-energized.
When should you use an ungrounded outlet?
If the wiring system into which you are installing an outlet has no ground available, use an ungrounded outlet. In an ungrounded system, an outlet with a ground contact would allow the outlet user to mistakenly, and perhaps dangerously, assume that a ground was present. A suitable ground may be available as a ground wire accompanying the hot and neutral wires in the cable, or a ground may be available via conductive conduit and a metal outlet box. In any case, use a tester to confirm the integrity of the assumed ground. A voltage test from the hot wire to the ground should show the same voltage as between hot and neutral (the black and white wires respectively). If you are replacing an ungrounded outlet, you need not assume there is no ground present. You may find, in the box, ground wires that were not connected to the outlet. You may come across grounded outlets that have no ground wire attached because they rely on grounding via the mounting screws through the outlet ears to the metal box. This is a less reliable grounding method. It is better to buy a ground-wire "pigtail," fasten the wire directly to a hole in the metal box with the supplied screw, and attach the other end of the ground wire to the outlet via the outlet's ground screw.
Can you run a double pole 30 amp breaker to two 110 recepticles?
No, A double pole breaker is going to give you 220 volts. 220 Volts is too much voltage for a 110 Volt outlet to handle. == Answer== Better to pull the duplex 30a and install to single-pole 20a breakers...if one kicks out, you will know which side the problem's on. And there's no problem with running a 20a circuit over 10awg wire.
What if a stud is located where an old work box must go?
Typically the old work box would go to just off the stud to either side. I can't think of a reason that dimension would be critical, and you should have no problem putting it on either side.
