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Demand factors for refrigerators in a laboratory #194004 05/04/10 06:21 PM
Joined: May 2010
Posts: 30
B
Bravo Offline OP
Member
Can I apply table 220.56 - demand factors for kitchen equip to laboratory refrigerators? The refrigerators are intermittent in use similiar to kitchen ref's.

thanks in advance.

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Re: Demand factors for refrigerators in a laboratory [Re: Bravo] #194006 05/04/10 07:03 PM
Joined: Jul 2004
Posts: 9,571
G
gfretwell Online Content
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I vote no. Refrigerators are basically motors.
I see this being 220.14(C) referencing 430.24

(125% of the biggest motor plus 100% of the rest).

If you are coming back from a power failure every one of those reefers will be presenting LRA at the same time. Depending on where you are, that can be a fairly frequent thing.

I am open to being wrong tho. wink



Greg Fretwell
Re: Demand factors for refrigerators in a laboratory [Re: gfretwell] #194024 05/05/10 09:12 AM
Joined: Jan 2004
Posts: 1,507
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George Little Offline
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I'm going to agree with Greg on this one for the reason he mentioned plus if we are talking about refrigeration type equipment there is nothing in Article 440 that I am aware of that allows us to apply a demand factor.


George Little
Re: Demand factors for refrigerators in a laboratory [Re: George Little] #194032 05/05/10 01:45 PM
Joined: Apr 2002
Posts: 7,234
HotLine1 Offline
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Agree with Greg and George!


John
Re: Demand factors for refrigerators in a laboratory [Re: HotLine1] #194035 05/05/10 03:24 PM
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Posts: 984
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ghost307 Offline
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Greg bring up an excellent point. After a power failure, that refrigerator will be running as a continuous load until it gets its contents cooled down. Some of that laboratory refrigerators that I've done go down to way below -100 degrees.


Ghost307
Re: Demand factors for refrigerators in a laboratory [Re: ghost307] #194049 05/06/10 11:28 AM
Joined: May 2010
Posts: 30
B
Bravo Offline OP
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thanks guys. I will size 125% of the biggest motor plus 100% of the remainders.


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