ECN Electrical Forum - Discussion Forums for Electricians, Inspectors and Related Professionals
ECN Shout Chat
Shout Box
Recent Posts
by Rabbit. 03/20/18 08:23 PM
Recall notice: Southwire wi-fi wall switches
by sparkyinak. 03/15/18 06:03 PM
Goodman Manufacturing Recalls Modular Blowers
by Admin. 03/13/18 10:40 PM
MAAX Spas Recalls Hot Tubs and Swim Spas
by Admin. 03/13/18 10:29 PM
New in the Gallery:
Housebilding DIY wiring
SE cable question
Who's Online Now
0 registered members (), 4 guests, and 10 spiders.
Key: Admin, Global Mod, Mod
Previous Thread
Next Thread
Print Thread
Rate Thread
Page 1 of 2 1 2
commercial load calcs #159331
12/08/06 10:43 PM
12/08/06 10:43 PM
eswets  Offline OP
Joined: Mar 2004
Posts: 55
Lansing, IL, USA
I need to do a load calc for a new service on a restarant. I know commercial differs from res, but I cant find anything on the matter. Any info or a template to do the calcs would be great.

Business, Office, Estimating, Legal:
Re: commercial load calcs #159332
12/11/06 04:03 PM
12/11/06 04:03 PM
ITO  Offline
Joined: Nov 2006
Posts: 348
They are not to hard to build up in excel.

101° Rx = + /_\
Re: commercial load calcs #159333
12/11/06 09:47 PM
12/11/06 09:47 PM
ITO  Offline
Joined: Nov 2006
Posts: 348
Ok I got bored and made one for commercial kitchens. I just took my commercial calc-sheet and added item #7 for kitchen equipment.


STOP, if you don’t know excel, then don’t download this, and don’t read any further. Using an ITO excel calc page without first having a clue about excel will only get you in trouble so don’t do it. You have been warned.

Commercial Load Calc XLS Sheet

Only edit the yellow fields, if the answer is none, put a ZERO in it. I put plug numbers in to test the formulas, do NOT “delete” the contents of any cell, just right-click and “clear contents”.

1) Enter your square footage, if you don’t know what the lighting package specs are, but if you do you should use the actual as per 220-14 (D)

2)Number or general purpose receptacles.

3)Water heater, if its gas just put “0” and “clear the contents” for the VA value.

4)Again “0” it out if none, otherwise put the known values in.

5)Heat, there aint no way around it.

6)AHUs run with heat or AC so they get listed, and the rest is up to you.

7)READ 220.56 and only put “kitchen” equipment in. These will de-rate automatically but you must put a “zero” in if there is nothing or the de-rate formula will count it. Also if you need more rows, then “insert” them in-between 12 and 13 or you will mess up the formula.

8)Sign circuit…duh.

9)May not be required for a restaurant but I have seen some with a show window, and it was already on my calc-sheet. Just “zero” it out if you don’t want it.

10)You have to do it, so suck it up.

11)You don’t have to do it, but it’s a nice way to “bump” it if you need too.

12)The calc for amps at the end is for 3 phase only so be careful if you do a single phase service and edit the formula.

13)I converted this in about 15 minutes, so there make be a mistake…use at your own risk.

14)Comments and criticisms welcome.

(let me find a host for the xls file, brb)

[This message has been edited by ITO (edited 12-11-2006).]

101° Rx = + /_\
Re: commercial load calcs #159334
12/11/06 11:07 PM
12/11/06 11:07 PM
Obsaleet  Offline
Joined: Apr 2003
Posts: 362
Thanks ITO,
Itlooks like a nice set up I will check it out.


Choose your customers, don't let them choose you.
Re: commercial load calcs #159335
03/01/07 11:42 AM
03/01/07 11:42 AM
Amazingmg  Offline
Joined: May 2005
Posts: 42
Florida, USA
I would like a copy of that spreadsheet if you could send it to me.

Re: commercial load calcs #159336
03/01/07 12:19 PM
03/01/07 12:19 PM
renosteinke  Offline
Cat Servant
Joined: Jan 2005
Posts: 5,316
Blue Collar Country
A new restaurant? Boy, does THAT bring back memories! I'd like to share a few pointers....

First of all, the load calc on the last place I did turned out to be optimistic. We had a number of problems, not the least of which was that the calcs put us over 320 amps, yet under 400.
Lesson #1: Push things with the PoCo. Better for them to up their metering before the place opens.

The next point is to look at the PoCo feed to the place. What else are those transformers feeding? Just because you're getting good voltage during construction does not mean there will not be voltage issues in the summer, when both the restaurant and the supermarket next door have their A/C running full blast!
In other words ... make sure the folks you are talking to at the PoCo actually considers that the new loads will overload the transformers.

Load calculations aside, be prepared to run a lot more circuits than you think you will need. For example, a coffee / soda station is likely to need at least 5 separate circuits. The ice machine, and the ice cream maker, are likely to require two circuits apiece.

Then there is the matter of the Ansul system. Again, you are likely to have a dozen circuits on the Ansul system. It might be easiest if you have a separate panel for these circuits. Think it over.

I know, I've gone well beyond simple load calculations. The place I did still likes me, though .. which is more than some of the other trades involved can say!

Re: commercial load calcs #159337
03/01/07 10:38 PM
03/01/07 10:38 PM
NJ_WVUGrad  Offline
Joined: Jan 2006
Posts: 47
Neptune, NJ, USA
One of Renos statements raises an interesting point that I remember running into

Many POCO's in NJ try to push using a 320A rated meter pan when we submit a load letter for keeps them from having to install CT's and the associated cabinet.

Because of this we really had to double and triple check our load calcs to put us over 320A.

Has anyone else run into this issue?

Re: commercial load calcs #159338
03/02/07 07:45 PM
03/02/07 07:45 PM
LK  Offline
Joined: Jan 2003
Posts: 1,429
New Jersey
"Many POCO's in NJ try to push using a 320A rated meter pan when we submit a load letter for 400A."

The 320A Meter Sockets are rated 400A max 320 is for continous loads only, when you submited your load calcs, did your continous loads exceed 320A?

Re: commercial load calcs #159339
03/03/07 07:06 PM
03/03/07 07:06 PM
WhiteRook  Offline
Joined: Feb 2004
Posts: 48
Republic of Texas
Ito, I too would like to see this. The link says it is no longer available for download so could you send me a copy please

Re: commercial load calcs #159340
03/05/07 12:43 PM
03/05/07 12:43 PM
ITO  Offline
Joined: Nov 2006
Posts: 348
Ok ok if I get some time I will upload the latest Rev of my Restaurant load calc sheet today.

101° Rx = + /_\
Page 1 of 2 1 2


2017 Master Electrician Exam Preparation Combos
2017 NEC Electrician
Exam Prep Combos:
Master / Journeyman


Member Spotlight
kamloops BC Canada
Posts: 1,142
Joined: May 2003
Show All Member Profiles 
Top Posters(30 Days)
Admin 5
Trumpy 5
Popular Topics(Views)
244,544 Are you busy
181,668 Re: Forum
171,714 Need opinion
Powered by UBB.threads™ PHP Forum Software 7.6.1
(Release build 20180101)
Page Time: 0.024s Queries: 15 (0.005s) Memory: 1.0261 MB (Peak: 1.2023 MB) Zlib enabled. Server Time: 2018-03-22 06:18:35 UTC