Clothes Dryer Circuit

[iwire]

Go back and read the posts-- I gave an article more than once. You may not agree with it but I did cite it.

It is no more, or no less a violation than when a homeowner installs a 12 amp window shaker AC on a GP branch circuit.

Or is it now against the NEC for an EC to install a GP branch circuit?

 

[Dennis Alwon]

I can't see that this is any different than installing any 30a BC with multiple 30a recepts on it IAW 210.21(B)(3). It IS a General Purpose Branch Circuit. Plug in dryers or welders or whatever you want as long as you load it within the constraints of 210.23(B)

I understand that but I don't see it that way. If I had a branch circuit supplying two motors that were direct wired would this be different. Suppose those motors were cord & plug connected- would that change things.

 

[Dennis Alwon]

It is no more, or no less a violation than when a homeowner installs a 12 amp window shaker AC on a GP branch circuit.

Or is it now against the NEC for an EC to install a GP branch circuit?

Sure we have no control what a homeowner does after we leave but IMO that is a different case when you are wiring for a specific appliance or utilization equipment.

 

[220/221]

I have seen dryers that were hooked up in 2 locations with one circuit. It used to be in the basement but got moved upstairs. The ec just left the old one on the same circuit. This is compliant, IMO.

What is the difference between this and the OP scenario? They seem identical to me.

 

[stew]

The load does not exceed the rating of the circuit unles it is plugged in. Then and only then does the load exceed the branch circuit rating. Un plugged loads arent loads they are just potential loads and thats why I do not think 210.23 prohibits this.

 

[Little Bill]

I can't see that this is any different than installing any 30a BC with multiple 30a recepts on it IAW 210.21(B)(3). It IS a General Purpose Branch Circuit. Plug in dryers or welders or whatever you want as long as you load it within the constraints of 210.23(B)

I'm neither agreeing or disagreeing but in residential, (the OP's situation) do you often see 30A general purpose branch circuits with multiple receptacles? ie:30A recep here and one there, just in case? I haven't seen this, doesn't mean some don't do it, I just haven't run into this. IMHO, be kinda hard not knowing the recep. NEMA configuration.

 

[kwired]

IMO, yes... I have seen dryers that were hooked up in 2 locations with one circuit. It used to be in the basement but got moved upstairs. The ec just left the old one on the same circuit. This is compliant, IMO.

Now what happens when the owner decides to plug his welder into the receptacle in the basement that was left energized?

I still think it does not violate any code section. However I don't necessarily think it is a good design choice.

 

[iwire]

The load does not exceed the rating of the circuit unles it is plugged in. Then and only then does the load exceed the branch circuit rating.

I will go further than that, appliances that are not running do not create a load.

The NEC recognizes this.

220.60 Noncoincident Loads. Where it is unlikely that
two or more noncoincident loads will be in use simultaneously,
it shall be permissible to use only the largest
load(s) that will be used at one time for calculating the total
load of a feeder or service.

'Unlikely' is not the same as 'never'.

 

[Dennis Alwon]

I know this isn't two ranges but how is it different then 2 12KW ranges. You cannot plug them into one 40 amp circuit--or even 2 dryers. Now you will tell me that the table is for calculation of a feeder or service. Right? So I have to run a feeder for 2 ranges that is sized "x+?" but for the two ranges I can run one branch circuit sized "x". Makes no sense at all.

 

[electrickangaroo]

Anytime you install a heavy duty electrical appliance it needs to have its own dedicated circuit with the appropriate size wire and circuit breaker. If you don?t have the appropriate dedicated circuit, an appliance may draw more current than the circuit can handle. so can you say potential FIRE ??? I would think common sense here would be a dedicated circuit..... i just read something about a separate dedicated ground to a dryer also. this went into effect here in the states in 1990 so that could be part of the answer

 

[Twoskinsoneman]

I'm neither agreeing or disagreeing but in residential, (the OP's situation) do you often see 30A general purpose branch circuits with multiple receptacles? ie:30A recep here and one there, just in case? I haven't seen this, doesn't mean some don't do it, I just haven't run into this. IMHO, be kinda hard not knowing the recep. NEMA configuration.

No you do not often see it since heavy loads generally are given a dedicated circuit. But that does not mean it isn't allowed. 210.21 and 210.23 specifically allow it IMO.

 

[Twoskinsoneman]

I will go further than that, appliances that are not running do not create a load.

The NEC recognizes this.


'Unlikely' is not the same as 'never'.

Thanks for posting this reference. After a while thinking about this thread I finally got to the question "what IS a load?" (Thinking just having it plugged in might be considered a load) Course I laughed at myself for thinking "what is a load".
I guess it depends on what the definition of "is" is...

This 220.60 makes it that much clearer for me.

 

[Dennis Alwon]

This 220.60 makes it that much clearer for me.

Allow me to muddy it. :grin: 220.60 is for feeders and service calculations not branch circuits. :grin:

 

[kwired]

Anytime you install a heavy duty electrical appliance it needs to have its own dedicated circuit with the appropriate size wire and circuit breaker. If you don?t have the appropriate dedicated circuit, an appliance may draw more current than the circuit can handle. so can you say potential FIRE ??? I would think common sense here would be a dedicated circuit..... i just read something about a separate dedicated ground to a dryer also. this went into effect here in the states in 1990 so that could be part of the answer

Can you give us a definition for heavy duty?

If load(s) are drawing more than circuit can handle the overcurrent device is supposed to open the circuit. That is not a fire hazard it is fire protection. It may be an inconvenience to the user. If they increase level of protection as a fix, then they have created a fire hazard.

No reason you can't have 4 conductors to one outlet and only use 3 to another outlet that doesn't require the 4th on the same branch circuit.

 

[Twoskinsoneman]

Allow me to muddy it. :grin: 220.60 is for feeders and service calculations not branch circuits. :grin:

Of course your right and I understood that all ready. But IMO it could be viewed, indicatively, as the way the NEC views loads that are plugged in but not turned on simultaneously. To me it is intuitive but it's nice to see at least a conceptually similar concept stated in the NEC.
Do you think any equipment plugged in should count toward the calculated load?

 

[Dennis Alwon]

Do you think any equipment plugged in should count toward the calculated load?

Does the NEC say that only direct wired motors should be counted... DW, Disposal, etc-- sure they are fixed but... 220.50 says motors shall be calculated in accordance with 430.24, .25 and .26--- does it say they must be direct wired?

 

[iwire]

Allow me to muddy it. :grin:

:grin:

Muddy yes.

I was surprised it took this long for someone to point out that the section I posted did not apply to branch circuits.


I did not consider that section a 'homerun' it was just an example that the NEC allows us to listen to the owners or operators of equipment when calculating a feeder or service.

 

[iwire]

. If you don?t have the appropriate dedicated circuit, an appliance may draw more current than the circuit can handle. so can you say potential FIRE ???

If we wire to that line of thinking every receptacle will have to be a dedicated circuit and muiti-tap strips will have to be outlawed.

The wire size and breaker will protect against fire.

i just read something about a separate dedicated ground to a dryer also. this went into effect here in the states in 1990 so that could be part of the answer

You do not understand the code section you are thinking of. Before the change we could use the neutral of the circuit to ground the dryer, after the change we had to bring an EGC to the dryer, not necessarily a 'dedicated' one.

 

[stew]

the staement that anytime you have a heavy duty load you need a dedicated circuit is an opinion not a code requirement.

 

[John120/240]

after the change we had to bring an EGC to the dryer, not necessarily a 'dedicated' one.

All conductors of one circuit must be in the same cable jacket or raceway. If the

EGC was not dedicated to the circuit that it was run with where would it come from? I can not grasp what Iwire is talking about?