Multi appliance branch circuits

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cppoly

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To size the OCPD for multiple refrigeration appliances on one circuit, you take the largest appliance OCPD and add the remaining FLA's and size up or down? For example, two under counter refrigerators at 2.3A each. OCPD for one appliance would be 15A then add 2.3A and round up or down to 15A or 20A?

What about mixed appliances (refrigeration, motor, heat) on the same circuit?

What about convenience receptacles on same circuit as appliances?

Sorry, lots of difference combinations here.
 
Does the wording of 210.23 answer most of your questions ?

210.23 Permissible Loads. In no case shall the load exceed
the branch-circuit ampere rating. An individual branch
circuit shall be permitted to supply any load for which it is
rated. A branch circuit supplying two or more outlets or
receptacles shall supply only the loads specified according
to its size as specified in 210.23(A) through (D) and as
summarized in 210.24 and Table 210.24.
(A) 15- and 20-Ampere Branch Circuits. A 15- or 20-
ampere branch circuit shall be permitted to supply lighting
units or other utilization equipment, or a combination of
both, and shall comply with 210.23(A)(1) and (A)(2).
Exception: The small-appliance branch circuits, laundry
branch circuits, and bathroom branch circuits required in a
dwelling unit(s) by 210.11(C)(1), (C)(2), and (C)(3) shall
supply only the receptacle outlets specified in that section.
(1) Cord-and-Plug-Connected Equipment Not Fastened
in Place. The rating of any one cord-and-plug-connected
utilization equipment not fastened in place shall not exceed
80 percent of the branch-circuit ampere rating.
(2) Utilization Equipment Fastened in Place. The total
rating of utilization equipment fastened in place, other than
luminaires, shall not exceed 50 percent of the branchcircuit
ampere rating where lighting units, cord-and-plugconnected
utilization equipment not fastened in place, or
both, are also supplied.

 
augie47 said:
Does the wording of 210.23 answer most of your questions ?

210.23 Permissible Loads. In no case shall the load exceed
the branch-circuit ampere rating. An individual branch
circuit shall be permitted to supply any load for which it is
rated. A branch circuit supplying two or more outlets or
receptacles shall supply only the loads specified according
to its size as specified in 210.23(A) through (D) and as
summarized in 210.24 and Table 210.24.
(A) 15- and 20-Ampere Branch Circuits. A 15- or 20-
ampere branch circuit shall be permitted to supply lighting
units or other utilization equipment, or a combination of
both, and shall comply with 210.23(A)(1) and (A)(2).
Exception: The small-appliance branch circuits, laundry
branch circuits, and bathroom branch circuits required in a
dwelling unit(s) by 210.11(C)(1), (C)(2), and (C)(3) shall
supply only the receptacle outlets specified in that section.
(1) Cord-and-Plug-Connected Equipment Not Fastened
in Place. The rating of any one cord-and-plug-connected
utilization equipment not fastened in place shall not exceed
80 percent of the branch-circuit ampere rating.
(2) Utilization Equipment Fastened in Place. The total
rating of utilization equipment fastened in place, other than
luminaires, shall not exceed 50 percent of the branchcircuit
ampere rating where lighting units, cord-and-plugconnected
utilization equipment not fastened in place, or
both, are also supplied.
Click to expand...

Yea that helps but only gives some insight. So there's no restriction on the number of appliances or the different type of appliances as long as individual loads don't exceed 80% if cord and plug appliance. I'm still unclear about mixing and matching multiple appliances on the same circuit and sizing the OCPD.
 
cppoly said:
To size the OCPD for multiple refrigeration appliances on one circuit, you take the largest appliance OCPD and add the remaining FLA's and size up or down? For example, two under counter refrigerators at 2.3A each. OCPD for one appliance would be 15A then add 2.3A and round up or down to 15A or 20A?

What about mixed appliances (refrigeration, motor, heat) on the same circuit?

What about convenience receptacles on same circuit as appliances?

Sorry, lots of difference combinations here.
Click to expand...

cppoly said:
Yea that helps but only gives some insight. So there's no restriction on the number of appliances or the different type of appliances as long as individual loads don't exceed 80% if cord and plug appliance. I'm still unclear about mixing and matching multiple appliances on the same circuit and sizing the OCPD.
Click to expand...

I think you are making this more complicated than necessary. For the typical kitchen two small appliance branch circuits on 20 A

OCPD & GFCI protected for counter top appliances. . Fridge either 15 A or 20 A OCPD. Garbage disposal

& Dish Washer on 20 A OCPD with a half hot recptacle for the disposal. Over the range microwave 20 A OCPD.

What multiple appliances do you want to put on the same circuit ?
 
Let's say a blender, garbage disposal, microwave, beverage center, plug in heater, juicer, television, and convenience receptacles. Not all on the same circuit. Generally most go on their own circuits. However some appliances are low enough amps that it can be combined with another appliance or two or three appliances on the same circuit. It's part confusing because if the appliance had a motor in it, you're supposed to follow Article 430. If the appliance has refrigerationin it, you're supposed to follow Article 440. It's the combining of multiple sections with different rules that's tricky. Yes I'm probably making it more complicated than necessary.
 
If this is a residence then you do not need to consider the appliance that are portable. Your 2 sabc's that are required for the kitchen counter will handle that. The others such as dishwasher I would put on their own circuit.
 
Dennis Alwon said:
If this is a residence then you do not need to consider the appliance that are portable. Your 2 sabc's that are required for the kitchen counter will handle that. The others such as dishwasher I would put on their own circuit.
Click to expand...
Not always. And don't forget, the same two or more SABC's supplying the kitchen countertop receptacles are also permitted to supply any receptacle in the rooms specified in 210.52(B)(1).
 
augie47 said:
Are you referencing hard-wired appliance or plug-in ?
Click to expand...
It's practically pointless to speculate until exact loads and wiring methods are determined. Short of such, the best one can achieve is an understanding of the complexities.

The closest to a simplified understanding is provided by 430.24...

Conductors supplying several motors, or a motor(s) and other load(s), shall have an ampacity not less than the sum of each of the following:

(1) 125 percent of the full-load current rating of the highest rated motor, as determined by 430.6(A)

(2) Sum of the full-load current ratings of all the other motors in the group, as determined by 430.6(A)

(3) 100 percent of the noncontinuous non-motor load

(4) 125 percent of the continuous non-motor load.
Click to expand...
 
Last edited:
Let us drop back to square 1 for a minute....'
I think your basic answer is in the following:
210.19. Your branch circuit conductors must have an ampacity to handle the load being served
210.23 Lists the permissible loads for circuits.
240.4 states you will protect those conductors at their ampacity (with exceptions)
More specific Articles such as 422, 430, 440 set limits on maximum overcurrent protection for specific loads.

Some of the appliances you listed such as the mcrowave have manufacturer instructions that require a dedicated circuit. Many the ones you listed would be plug-in household appliances. You have no control over which ones and how many will be plugged in... the Code sets a MINIMUM standard to provide power for such appliances and requires that those (minimum) circuits be installed properly.
The customer, the contractor, engineer, or designer can request/require more than the Code minimum.
 
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