Simple circuit add to panel question

[TTA89]

Never done this before... Just triple checking so I don't do it wrong.

I'm wiring up a new 20amp circuit for T5 lights. I have the romex run to the bottom of the panel. This is the garage panel which has a 100amp feed to a subpanel at the house. I'm going to flip the top main breaker to cut all power and then I'll install a clamp on the knockout at the bottom to hold the romex in place. Cut off the romex sheathing from the clamp into the box. I'm going to run the wires up the right side and plug them into the 20amp breaker that is already there but empty. (running 12/2)

I don't really understand why they aren't separated so I'm copying what is there but White and copper ground go to the same "bar", I'll screw each one into it's own screw on the same bus on the right. Then the black goes to the 20amp breaker.

Flip on the main, flip on the 20amp breaker, see if the lights work. Any issues with that?

 

[pattenp]

You are doing it right. The neutrals and grounds go to same bar only in the main service panel where the first main disconnect is located. Other panels fed from the main panel are to have the neutrals isolated from the ground.

 

[Kaizen]

just a few tips to add. cut some cardboard and put it over the open bus between the double breaker and the others. also cover the top lugs same way.
put the romex up to the panel and get the approx. length you need routing it as you want plus a foot. cut the romex and attach to the romex connector. slip the 3 wires up through the hole pulling back toward you until connector is in hole. then slide the nut down the wires and screw on. start working on the ground first. because its exposed the entire length it has the most chance of hitting something hot.
stand on a few 2x4 scraps to minimize conductivity.
have fun.

 

[manwithtools]

A point to remember that has been partially addressed is the fact that even with the main beaker off there is still power in the breaker panel. The lugs at the top of the main breaker will still have power on them and extreme care needs to be exercised to ensure you or the wire you are working with don't come in contact with those.

 

[matt_i]

All screws you land a wire on/under = very tight.

 

[Norcal]

A point to remember that has been partially addressed is the fact that even with the main beaker off there is still power in the breaker panel. The lugs at the top of the main breaker will still have power on them and extreme care needs to be exercised to ensure you or the wire you are working with don't come in contact with those.

There is no overcurrent protection (fuse or circuit breaker) between the transformer & the line lugs on main circuit breaker, so a mistake can be very serious.

All screws you land a wire on/under = very tight.

Too tight is just as bad as too loose, manufacturers instructions do include torque values, the NEC requires that the instructions included with equipment be followed, 110.3(B) the only way to do so is with proper torque tools.

 

[TTA89]

Thanks guys! I had my wife standing out there with a broom and told her to knock me over if I started getting shocked. She didn't think it was amusing

I wired in 3 new circuits for 15x 8 Foot T5 fixtures. It looks awesome! Now I can get to work on stuff IN the garage instead of ON the garage.