Coffee Pot Question

[GoldDigger]

And when the tank reaches the set temp it turns off. If they were always on it would eventually boil the water, and by boil I mean we would have high pressure steam start developing in there, if it were not used fast enough.

The point is that turning the unit off using the obvious switch (brew on/off) rather than a disconnect does not insure that the holding tank heater will not start drawing current at an unpredictable time. But it would not be a continuous load in terms of ampacity calculations.

 

[ActionDave]

Do you see any need to increase the wire size?

Sure. That deep feeling of satisfaction that comes from over-engineering.:roll:

 

[kwired]

The point is that turning the unit off using the obvious switch (brew on/off) rather than a disconnect does not insure that the holding tank heater will not start drawing current at an unpredictable time. But it would not be a continuous load in terms of ampacity calculations.

That is what I was getting at, the load is not continuous, even if the appliance is "always on".

 

[liquidtite]

Don't you have to stay under 80percent when sizing Ocp 16 amp for 20 amp circuit

 

[ActionDave]

Don't you have to stay under 80percent when sizing Ocp 16 amp for 20 amp circuit

If you have to do that then yes, but you don't always have to. You can load a 20A circuit all the way up to 20A.

 

[liquidtite]

When do you have to stay under 80percent

 

[ActionDave]

When the code says so. Electric water heaters, commercial lighting loads, anything that meets the definition of a "continuous load" (make sure you read all of the definition) and a few others. Once you eliminate those you can load up your circuits right up to the limit.

 

[infinity]

Don't you have to stay under 80percent when sizing Ocp 16 amp for 20 amp circuit

If it's non-continuous then you go up to 100% for an individual branch circuit. A few code sections:

II. Branch-Circuit Ratings
210.19 Conductors ? Minimum Ampacity and Size.
(A) Branch Circuits Not More Than 600 Volts.
(1) General. Branch-circuit conductors shall have an am-
pacity not less than the maximum load to be served. Where
a branch circuit supplies continuous loads or any combina-
tion of continuous and noncontinuous loads, the minimum
branch-circuit conductor size, before the application of any
adjustment or correction factors, shall have an allowable am-
pacity not less than the noncontinuous load plus 125 percent
of the continuous load.

210.23 Permissible Loads. In no case shall the load ex-
ceed 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.

 

[kwired]

Or if the breaker is designed for continuous loading at 100%.

You will not find any of this design in the common "miniature" series breakers found for typical 120 - 240 volt applications.

Probably will not find any for most industrial applications either that are less than 400 amps rating.

 

[David B Rivera]

Comercoal Kitchen Equipment

Comercoal Kitchen Equipment

Is it cord and Plug connected? That would limit it to 80% of the branch circuit. Appliances over 13.3 amps can be sized to 150%. I have found through experience that a larger circuit will work better. The weak point is usually the plug and the receptacle type connection. If it is hard wired the connection problems are eliminated. If the appliance is used all day, then I would use a larger circuit than 20 amp/ #12 cu. I have built and maintained many Restaurants the smaller circuits will work but don't last.

 

[David B Rivera]

English and Bad English

English and Bad English

You say commercial I say what?

 

[infinity]

Is it cord and Plug connected? That would limit it to 80% of the branch circuit. Appliances over 13.3 amps can be sized to 150%. I have found through experience that a larger circuit will work better.

Can you provide some code sections?

 

[hurk27]

Is it cord and Plug connected? That would limit it to 80% of the branch circuit. Appliances over 13.3 amps can be sized to 150%. I have found through experience that a larger circuit will work better. The weak point is usually the plug and the receptacle type connection. If it is hard wired the connection problems are eliminated. If the appliance is used all day, then I would use a larger circuit than 20 amp/ #12 cu. I have built and maintained many Restaurants the smaller circuits will work but don't last.

If the appliance comes with a factory installed cord and plug cutting off the plug to install a higher amprage one is a violation of the UL listing for that appliance, also the condutors the factors uses in the appliance might have been sized for the protection of a 20 amp circuit using the appliance on a higher rated circuit could also create a fire hazard.

the 80% requirement you mentioned above is for two or more receptacles on a branch circuit, read 210.23

Or here I'll post it:

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.

 

[David B Rivera]

Hot Coffee

Hot Coffee

210.23(A)&(B) Gives the 80%, 422.11(E)(3) gives the 150%. If it comes with a 20 amp factory cord, you would think it would be limited to 16 amps on a 20 amp circuit. Of course you need to follow manufactures instructions. A lot of the commercial equipment doesn't come with a cord or plug.