Couple of questions

[alan camby]

1. Had a electrician many years ago tell me that a receptacal cannot be used as a terminal strip. Meaning that a regular receptacal cannot have the black line wire on one brass colored screw and a load black wire on the other brass screw. I have seen many homes wired to daisy chain from one outlet to the next. I have been running the two romex cables into the receptical box and using a red wire nut to tie the 2 blacks with a 3rd short piece of black wire to feed to the receptacal. The white wire gets the same treatment.

What about the spec grade receptacles with the wiring holes on the back and the screws that pulls a bar to clamp the wire. Total of 4 holes for the black and four for the white. Can i put the two blacks in two close holes on the hot (brass colored) side and have the one screw tie them? Same with neutral side (silver colored). Can I choose one of the 2 holes that are clamped by one screw? This way I would not have to go thru the wire nut procedure.
If this cannot be done, Why are there 4 wire holes on both hot and neutral?

2. Are you guys putting GFCI receptacles in pole barns? If so, Is it code? What about 220vac outlets for welders that use plugs? What about 220 with disconnects and conduit ran to the load like a large compressor?

3. Where are arc fault breakers required to meet code?

4. See many homes with 20 amp breakers (with proper 12 gauge wire) and 15amp rated receptacls and switches. Does this meet code? For the extra $.50 i would use the 20 amp stuff, but is 15amp ok?


Thanks

 

[alan camby]

Also, What about orange receptacles. Any place in the home or home shop that these are needed?
These have a isolated ground.

 

[Charles (in GA)]

There is no requirement that prevents the wires from daisy chaining from one receptacle to the next. It is better to bring the wires into the box, add a 6 inch or so pigtail and wirenut them together, and connect the pigtail to the receptacle...... and in Multi-Wire Branch Circuits (MWBC) (meaning, a shared neutral system) the neutral side MUST be pigtailed, by code.

As far at the 15 amp receptacle and 20 amp circuit, it is quite legit, by the NEC, to use two or more 15 amp receptacles on a 20 amp circuit. A common duplex receptacle is TWO receptacles, again, per code. If you buy better quality 15 amp receptacles, you will find they have 20 amp guts inside of them, so if you are going to have to pay more for the 20 amp ones, don't bother, you are not gaining anything. Look inside a 15 amp spec grade receptacle and you will find on the neutral blade, the same contacts as used on the 20 amp with a T slot, they just block off part of the contact with the face plate on the 15 amp version.

Don't spend any extra money on the Isolated Ground receptacles, you have no need for them.

You will not need any arc fault breakers in a detached garage, however, on grade level, you will need to Ground Fault protect the circuits, whether you do that with GFCI receptacles, or breakers is your choice. For the long run, you would be better off with the GFCI breakers, as these are probably of better quality, and if you do trip one, you will know where to find it to reset it, as opposed to a receptacle in the beginning of a circuit and its hidden behind a workbench, toolbox, etc.

GFCI not required on 240v circuits unless they are hot tubs, etc, that specifically require it. GFCI is not required on 120v circuits above grade level (meaning second floor) of the detached garage either.

Charles

 

[alan camby]

The reason for not daisy chaining, a least what i was told, was because the bar that connects the the top and bottom of the receptacle could become the weak link. If the receptacle was consistantly overloaded the link could act as a fuse.

Please explain the multi wire branch circuit thing. I thought I was always sharing the neutral from receptacle to rec.

 

[Charles (in GA)]

MWBC is when you have two hots, opposite sides of the bus, meaning 240v, and a neutral. If you go neutral to hot you have 120v, hot to hot you get 240v. For example, you can run 12/3 w/ground Romex and connect the black and red to a double pole breaker, then run to a box with two receptacles, and connect the neutral to both receptacles and one hot to one rec and the other hot to the other rec, and you have a MWBC. Its purpose is to save wire. On the neutral, when the sine wave of one side of the bus is going up, the other side of the bus is going down, thus the neutral, while shared by two hots, is not overloaded, so long as the two hots are powered by opposite sides of the bus.

I highly recommend you NOT attempt any MWBC unless you know exactly how to do it, and have a specific reason for doing it. It creates way too much confusion down the road in the future. I did this on my lighting, as putting all 4 of my metal halides in each row on one circuit would come right to the 80% limit of the circuit 16 amps on a 20 amp circuit (each light draws 4 amps) and I just did not want to be running right on the edge all the time.

Charles

 

[alan camby]

Thanks.

That 12-3w/g is crazy expensive. I just bought 50 foot of it and was $51.77 at Menards

250 foot of 12-2w/g is running about $63.29 at Menards.

Did not see the 250' rolls of 12-3 there.

 

[Norcal]

Also, What about orange receptacles. Any place in the home or home shop that these are needed?
These have a isolated ground.

If you have a dedicated circuit w/ NM cable it is a isolated ground circuit, no need to spend the big bucks for orange isolated ground receptacles. That does not mean someone really needs it...