# breaker size calculation for the freezer according to NEC

Discussion in 'General Electronics Chat' started by tahir mehmood, Sep 14, 2015.

1. ### tahir mehmood Thread Starter New Member

Jun 28, 2013
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0
we have a special type Freezer, it is single phase 240v, 60 hz, the full load amperes are 10A, I need to calculate the breaker size for it according to NEC.

2. ### tahir mehmood Thread Starter New Member

Jun 28, 2013
21
0
My calculations are:

FLA * 1.75
10*1.75=17.5 240.6(A) and 440.22(A) as per NEC.

Am i doing the correct calculation?

3. ### #12 Expert

Nov 30, 2010
17,895
9,314
It is difficult to know the electrical code when we can't tell what country you are in.

4. ### Johann AAC Fanatic!

Nov 27, 2006
190
30
Where I live, the breaker in the distribution board protects the wiring of the installation and not the appliance plugged into a socket. It should have its own integral protection.

shortbus likes this.
5. ### MikeML AAC Fanatic!

Oct 2, 2009
5,451
1,071
Same in the USA and CAN; likely also in the EU.

Breakers at the distribution panel are chosen based on the wire gauge of the branch circuit; not on the individual appliance...

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6. ### KeepItSimpleStupid Well-Known Member

Mar 4, 2014
2,069
359
It's not a continuous load, but you have not specified distance to the load. 500 or 30' could make a difference.
So the breaker would be the next size up after doing the voltage drop calculations. I believe you want less than 3%.
If it were continuous - on or more than 3 hours at a time, I believe, sizing would start at 125% or (1/0.8).

7. ### Johann AAC Fanatic!

Nov 27, 2006
190
30
These calculations should be done during the design of the electrical installation. This will ensure correct sizing of the wire gauge of the branch circuit. The size of the breaker will then relate to the current-carrying capacity of the particular gauge of wire used, but as was mentioned before, this has no relevance to the needs of the appliance which should have its own integral overload cut-out or other form of overload protection.