Dumb waiter service calc

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arnettda

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When doing a load calculation for a new service can I consider a dumb waiter a fixed appliance and derate it according to 220.53 ? It is 120 volt and is not my largest motor load.
 
Article 220.53 only allows a demand factor for multiple appliances (four or more.) Are there four dumbwaiters?

A single dumbwaiter would be grouped under the demand calculation of article 220.82(B)(3)a.
 
JoeStillman said:
Article 220.53 only allows a demand factor for multiple appliances (four or more.) Are there four dumbwaiters?

A single dumbwaiter would be grouped under the demand calculation of article 220.82(B)(3)a.
Click to expand...

When taking taking demand factor for multiple appliances you don't have to have 4 or more of the same appliance.
 
JoeStillman said:
Article 220.53 only allows a demand factor for multiple appliances (four or more.) Are there four dumbwaiters?

A single dumbwaiter would be grouped under the demand calculation of article 220.82(B)(3)a.
Click to expand...

One dumbwaiter 6 other appliance I defaced for.
 
edward said:
When taking taking demand factor for multiple appliances you don't have to have 4 or more of the same appliance.
Click to expand...



220.53 Appliance Load ? Dwelling Unit(s).It shall be permissible to apply a demand factor of 75 percent to the nameplate rating load of four or more appliances fastened in place, other than electric ranges, clothes dryers, space-heating equipment, or air-conditioning equipment, that are served by the same feeder or service in a one-family, two-family, or multifamily dwelling.
Click to expand...

My understanding of this passage is that the likelihood of all appliances to be on at the same time decreases as the number of appliances increases.
 
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