I need to wire a 3 gang switches in a 3 gang box

You have 2-gang switch.
Look at following illustration showing gang switches:
http://waterheatertimer.org/How-to-wire-switches.html#gang

Hot wire feeds one screw on first switch, and then jumpers to second switch.
Your jumper wire is connected wrong place.

Find hot wire... there will be 1 hot wire entering gang box.
Disconnect all wires, and separate for testing.
Turn power on and test each wire to bare ground wire... that will show the hot wire.

Sorry it is difficult to post question on fixya, or communicate with people answering free questions.

Gene h

If you need further help, I’m available over the phone at https://www.6ya.com/expert/gene_9f0ef4df2f9897e7

Copy following links:
http://waterheatertimer.org/How-to-wire-switches.html#gang

http://waterheatertimer.org/images/3-gang-box-800.jpg

You have to test which wire is neutral.... usually white wires twisted together and covered with wire nut in back of box.
Hot wire with test 120volt to neutral.
Hot wire will test 120volt to ground.

Gene
h

If you need further help, I’m available over the phone at https://www.6ya.com/expert/gene_9f0ef4df2f9897e7

Hi John,

I'm an electrician and can help you with this question.

The *best* way to plan for this fixture is to install a "3-wire" cable (romex, bx, etc.) designated as "14-3" where "14" is the size of the conductors and "3" is the number of insulated conductors. A "three wire" cable consists of 3 insulated conductors (white, black & red) and an uninsulated or bare conductor. Sometimes, you may find that the cable has 4 insulated conductors and instead of a bare conductor it will be covered with green or green with a yellow stripe insulation. This 4th wire is the ground wire (insulated or not). Either type of cable is acceptable for use.

By installing a 3 wire cable, you will not be required to use a "special switch" or an "RF switch" which are often much more expensive to purchase and more involved to install. You can use two independent switches, consisting of a variable dimmer for the light and a speed controller for the fan, simple "snap" or "toggle" switches or any combination of both if you install into a "2 ganged box". If you opt to install a single gang box, your switches will be needed to be on a single strap (often called duplex switches) and your choces for control will become limited - and likely more expensive, too.

If you run a 3 wire cable, you can install your choice of switches, if you install only a 2 wire cable, you will be forced to use special switches or a standard switch and a pull chain on the fixture (this option is only available to you if there is a constant power source at the fixture). It will cost a little more for the 3 wire cable, but it will provide the most flexibility when selecting fans / switches.

I hope this was helpful & good luck!

I think you mean that you need to wire a set of three way switches. That is when you have a switch at two locations to run the same load (lights for example). Without being able to draw a picture, I will try to explain this the best I can. You have probably 120 volts coming in on a 14-2 romex for a 15 amp circuit or a 12-3 romex for a 20 amp circuit consisting of a black, white, and a bare wire. You run that set of wires to one of the two switches. Then from that switch you need to run a type of 3-wire cable from that switch to the other. For example:14-3 romex for a 15amp. circuit or 12-3 romex for a 20 amp circuit. Do not reduce wire size if you start with 12 gauge wire coming in from the breaker. Then you again run a piece of 12-2 or 14-2 (depending again on the amp circuit you are running) from the second switch to the load or lights that the switches are serving. Now for terminating the wires. In both switch boxes you just connect the white wires together with a wire nut. The bare wires you also connect together with a wire nut, but also twist a short piece of bare wire in the wire nut. That tail will serve as your jumper to the green screw on the switch. Then all you should have left in each box is two black wires and a red wire. These three wires all go to the switch. On the switch you should have three screws on the sides. One is darker than the other two. That darker screw gets the black from the 14-2 or 12-2. Then all thats left is the black and the red that come from the 14-3 or 12-3. Those two go to the remaining two screws on the switch. It does not matter which one either goes on. That should do it now you just wire the light like you would any other.
Hope this helps. Any other questions feel free to email me.
P.S. Don't forget to turn off the power!!

OK, your new switch will require the use of a neutral wire. So you will have to do what is called a pigtail. You will have to twist another white wire in with your other white wires to attach your neutrals to your switch. Note: white wires are called neutral not common. Hook the wires that were originally hooked up to your LINE to your HOT (Black) on your new timer, and the what was originally LOAD up to the new timer LOAD. SO as far as wiring all that will change is your white wires that need to attach to your timer NEUTRAL.

Only if you have two separate 12/2 lines.

You need 12/3 w ground, because this is needed to connect the two switches and carry the neutral.

You can start with 12/2 power going to switch, then 12/3 from switch to switch, the 12/2 to fixture.

Tell me what you are wanting to accomplish. Are you wanting to run each fan off a separate switch in the same duplex box? The reason I ask is because you are using 12/3 wire to the fans. If you are just going to have 2 switches then you are only going to have power to each fan from each switch. Therefore there is no need to run 12/3 wire. 12/2 is all that is needed and you would simply tie the fan and light wires to that one power source at the light/fan. Now if you are wanting to have a switch for the light and another switch for the fan at each location then that will take 4 switches. You can buy double stack switches and have 4 switches in a double gang box. Is this new construction or old? Please explain what you are wanting and I will be more than happy to explain how to wire it.

there is a simple way and a not so simple solution, the simple solution is to take down the light fixture and replace with a pull chain fixture. I would have to know the building type commercial ...residential...is it hard piped and so on. In a residential setting the solution would be to install a piece of 14-2 romex between the fixture and the switch. 14-2 with ground is a flat cable with 3 wires (2 insulated and 1 bare). do not attempt with the power source on. the white insulated wire should be connected to the black wire in the fixture box, the other end of the white wire in your new piece of romex should be attached to one pole of the switch. the black wire in your new piece of romex should be attached to the black wire or gold screw of your fixture and the other end of your wire should be attached to the other pole of your switch. Now the other wire(the bare ground)if not attached will not affect the operation of the switch or light, but it is a safety which should be installed. all grounds should be connected to insure that any faulty wiring will trip the breaker saving anyone from getting shocked.

WARNING: Do not attempt to do this work unless you completely understand the information provided below. If in doubt call an electrician.
Always make sure the power is disconnected from all possible sources before making any connections. Your description of the problem indicates that there may be multiple power wires coming into the same box. In that case local codes may require that the box be partitioned to prevent exposure to voltages up to 220 volts.
You need to determine where each wire goes to know how to connect them together. You cannot rely on color alone. If the power supply runs through the box to the loads then most (but probably not all) of the white wires will be connected together. If the power runs to the load boxes first then none of the white wires in the switch box should be connected together. They are used to run the switched/dimmed power back to the loads (and should be taped to cover the white in the box). In that case each switch has its own power input and they should not be tied together. A wire (could be black or white with black tape) brings power from the load box, gets connected to the input terminal of the switch and the corresponding black wire carries the switched power back to the load. The fan/light switch will have one power in and a switched power out for the fan and another for the light. The 3-way will have one "power" in (or it could be the final power out to the light) and two "carrier wires that connect to the other 3-way switch. If the power supply goes through the switch box then there will be at least 10 wires in that box. In that case see the attached diagram:

The proper way to wire two switches in a 2 gang switch box to control each light separately is as follows:

1. Make sure you have the power turned off at the breaker for this box.
2. Take the HOT (common, black wire) FEED wire and add (2) pieces of black wires to it with a wire nut.
3. Now you can put one of each of these black wires to the bottom screw of each light switch to provide power to both switches separately
4. Connect each separate wire to the (2) different lights to the top screw of each switch.
5. Twist all the bare ground wires together, leaving at least 7-8 inches at the ends untwisted for at least 2-3 of these wires.
6. Take (2) of these ground wires and connect them to the ground screws on each separate switch. If it is a metal box these area in, connect one ground wire to the box with a green grounding screw also, if not, cut off the extra ground lead near the twisted bunch.
7. Now twist all white (netural) wires together and install them all under one wire nut.
8. Make sure the bare wires are not near or touching the HOT screws and fasten the switches to the box.

You now have an approved and legal wiring for (2) separate light switches using the one power source (FEED) already in the box.