New Electrical Work

I really do not see how this would be an infringement on the panel space and from a safety standpoint I see no problem with it. Of course I would not want to touch the panel if the floor was wet even though it would be no real safety issue if the panel was wired correctly. Just use common sense.

As safe as they are installed against any surface. If installed corrected they are very safe.

At 120 volts it will pull 4.166 amps. At 240 volts it will pull 2.08 amps.

A 200 amp service panel with a 60 amp sub-panel.

The equation for amperage is I = W/E, Amps = Watts/Volts. The amperage for the furnace would be, Amps = 15000/240 = 62.5 amps. So to answer the question, yes a 100 amp breaker with a #4 copper conductor will be sufficient to operate a 15 kW furnace. A 70 amp breaker will work but it is cutting the edge a bit too fine as you don't need the furnace to trip off during the winter months (northern hemisphere) if you are away from your home for an extended period of time.

# 4 copper wire short distance.

O course it is very dangerous. Moisture should never ever be allowed near a service panel.

It is different in different states. You are dealing with 2 separate codes here. HVAC & Electric codes. Contact both your electrical inspector and whoever inspects gas HVAC for a definite answer.

You want four switches to independently turn 4 lights on and off. You need two 3-way switches, and two 4-way switches. The first 3-way is located where the power first comes into this system, two travelers (wires) go to the first 4-way switch, two travelers then go from that switch to the other 4-way switch and two wires go to the final 3 way switch. The third wire on the last 3 way switch then goes to the first light fixture. This is a complicated wiring project and it is not as simple as it sounds. Realistically, you will have more than 2 wires traveling between switches depending on whether the neutral is located, and further more dependent on whether power from the panel first comes to a switch or to a light fixture. You need to plan this well or you may have more wires in one or more boxes than code allows. Also, wires must be attached in particular positions on all the switches, or you will end up with a situation where some of the switches will work and some won't and troubleshooting is very complex.

The procedure (leave the formula to the electrical engineers) is to first determine the amperage required to handle the load (check code for allowed percentage of breaker amperage that can be used depending on what type load you have), determine breaker size which will tell you the minimum size wire (from code tables such as # 12 for 20 amp or # 14 for 15 amp, etc). Then determine type of insulation which depends on whether location is wet or dry, interior or exterior, and whether cable must be individual solid or stranded wires, or cables and type of conduit if any. All specified in governing code.

A 30 amp breaker run 75 feet would require you use AWG #10 wire. But, an oven normally pulls more that 30 amps and I would not use #10 wire on a 30 amp breaker for an oven. Normally any newer oven is wired with AWG #6 gauge wire on a 50 amp circuit breaker so the breaker will not trip during heavy use of the oven. Some older ovens could use a #8 wire on a 40 amp breaker.

Not exactly sure what your question is and you need to make sure you are in compliance with electrical code for your jurisdiction. But, generally speaking you install a large breaker (let's say 100A 2 pole breaker to power the sub panel) just as you would install any other breaker in the presently used (hot) panel, and the proper sized cable then goes from old to new and terminates on the main lugs of the new panel. Ground and neutral are usually isolated from each other in the sub panel but depends on other factors as to location of the sub panel, etc.

Assume this is a ground fault circuit interrupter (GFCI) outlet. The GFCI looks for current that is flowing to ground, in a manner that could result in electrical shock to a user. The appliance that is being plugged in could be defective, the wiring connected to the load side of the GFCI may be incorrect, or the GFCI outlet could be defective. Try using another appliance. If the GFCI holds, the first appliance is most likely the cause.

Heating device or heating element.

AWG #3 copper.

Re Question with the voltage that you will be using.

AWG #10 copper on a 30 amp breaker.

978 watts

Yes, as long as it is in a plastic conduit.

If you want to operate the conductors maximum capacity, the conductor needs the heat, that the amperage produces, to be dissipated. This is why in the electrical code book there are two amperage ratings. The first one is for a free air rating which allows for a high ampacity of the wire. The other rating is for three conductors in a conduit which confines the cooling capacity and so the ampacity rating of these wires is lowered. The same procedure is used in cable spacings in ladder tray networks.

At least two different methods. One is to run power from panel to one light, then to the next, then next, then next. Run separate cable from each light to the switch location where you want the control.

Other way is to run power from panel (hot, neutral and ground) to first switch box, then an identical cable to the light #1, contine always hot wire from switch box 1 to switch box 2, then identical cable to light 2, repeat 2 moe times.

If you are talking about 4 switches in one box, use pigtails from incoming (from panel) hot to each switch--then apply that concept to the options listed above for switches in different locations. Watch and anticipate/plan how many conductors will be in each box and check code for maximum wires in various size boxes.

Deoends on code you are governed by. In USA, a GFCI outlet or a circuit controlled by a GFCI circuit breaker would be required.

You could solder them together and then tape securely with electrical tape.

Metal conduit must be buried to at least 6 inches.

Non-Metal conduit must be buried to at least 18 inches.

Direct bury wire must be buried to at least 24 inches.

This is what the NEC requires but your local codes may be even deeper. Check with your local utility to see what they require.