I am designing a service for a small strip mall. It will feed 1 house panel, 1 hardware store(2,000 square feet) and 1 grocery store (4,400 square feet). The only info I have is that the voltage will be 120/208Y from a transformer set by the power company. The Grocery store will have a 7.5 ton rooftop unit and about 68 4 lamp 2x4 troffers. That is all I have. I have no idea what a typical service for this size of a grocery store would be. Any grocery store guru's out there? Please help in any way you can.
Grocery store service
- Thread starter avr
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bphgravity
Senior Member
- Location
- Florida
Re: Grocery store service
Perhaps you shoul dreceive more information icluding the exact loads the will be served so an accurate load calculation can be made.
How is the place going to be built without plans review from the building department? Surely this information will be required by the AHJ.
Perhaps you shoul dreceive more information icluding the exact loads the will be served so an accurate load calculation can be made.
How is the place going to be built without plans review from the building department? Surely this information will be required by the AHJ.
jimwalker
Senior Member
- Location
- TAMPA FLORIDA
Re: Grocery store service
So bid on something real cheap like 2 200 amp services and only the lights and recepts that are on print.Once they allow you to start you can name own price on all the upgrades
So bid on something real cheap like 2 200 amp services and only the lights and recepts that are on print.Once they allow you to start you can name own price on all the upgrades
physis
Senior Member
Re: Grocery store service
Go look at some Safeway service's. You're not gonna get much closer than that.
I wouldn't waste too much time on the proposal without talking to somebody who makes decisions. If this is a competitive bid then do as Jim suggests, bare minimum.
I'd wager that this isn't an attempt to install what the store requires, but rather an effort to get a final.
Go look at some Safeway service's. You're not gonna get much closer than that.
I wouldn't waste too much time on the proposal without talking to somebody who makes decisions. If this is a competitive bid then do as Jim suggests, bare minimum.
I'd wager that this isn't an attempt to install what the store requires, but rather an effort to get a final.
- Location
- Illinois
- Occupation
- retired electrician
Re: Grocery store service
Be real careful with a design and build. Make sure you know what the contract requires. You may be obligated to make everything in the store work no matter what you have included in the cost estimate without additional compensation. Have an attorney review the contract before submitting a price.
Don
Be real careful with a design and build. Make sure you know what the contract requires. You may be obligated to make everything in the store work no matter what you have included in the cost estimate without additional compensation. Have an attorney review the contract before submitting a price.
Don
Re: Grocery store service
Hello AVR,
Sounds like you should be careful with this one mate.
I'm not a mechanical systems designer but even I would take note that 7.5 tons of cooling is not sufficient for this space. Typically 1 ton per 350 square feet should be provided, at the very least a 12 ton unit. I'll bet this ends up with two 7.5 ton units. This type of store will utilize self contained refrigeration equipment and this will reject heat into the space adding to the HVAC load on the building.
With that in mind lets assume an HVAC load of 42A x 360 (x2 units) = 30.3 kw
Lighting 68 x 115va each = 7.8 kva, but of course you need perimeter security lighting, store signage, additional display lighting. Lets add in another 5.0 kva for a total lighting load = +/- 13.0 kva
This store will probably utilize self contained refrigerated food storage (meaning compressors built in to the equipment). For this equipment lets use a watts per square foot number of 10 W/sq ft.
4400 x 10 = 44.0 kva Refrigeration Equipment
Lets add in a receptacle load (miscellaneous equipment) of 3va/ sq ft 4400 x 3 = 13.2 kva
Total Connected Load = 100 kva
Main Switch = 100,000 / 360 = 277A x 1.25 (future) x 1.25 (main switch usually not continuous rated) = 434 amperes
Therefore consider a 600 ampere minimum switch size for the grocery store. This may be conservative, but considering the lack of information you are dealing with you need to cover your tail. You are the design professional in this instance. I understand the financial appeal of low balling and then submitting excessive change orders to recoup additional money, but in this instance heed Don's advice before you do that. You may not legally have that option.
Hello AVR,
Sounds like you should be careful with this one mate.
I'm not a mechanical systems designer but even I would take note that 7.5 tons of cooling is not sufficient for this space. Typically 1 ton per 350 square feet should be provided, at the very least a 12 ton unit. I'll bet this ends up with two 7.5 ton units. This type of store will utilize self contained refrigeration equipment and this will reject heat into the space adding to the HVAC load on the building.
With that in mind lets assume an HVAC load of 42A x 360 (x2 units) = 30.3 kw
Lighting 68 x 115va each = 7.8 kva, but of course you need perimeter security lighting, store signage, additional display lighting. Lets add in another 5.0 kva for a total lighting load = +/- 13.0 kva
This store will probably utilize self contained refrigerated food storage (meaning compressors built in to the equipment). For this equipment lets use a watts per square foot number of 10 W/sq ft.
4400 x 10 = 44.0 kva Refrigeration Equipment
Lets add in a receptacle load (miscellaneous equipment) of 3va/ sq ft 4400 x 3 = 13.2 kva
Total Connected Load = 100 kva
Main Switch = 100,000 / 360 = 277A x 1.25 (future) x 1.25 (main switch usually not continuous rated) = 434 amperes
Therefore consider a 600 ampere minimum switch size for the grocery store. This may be conservative, but considering the lack of information you are dealing with you need to cover your tail. You are the design professional in this instance. I understand the financial appeal of low balling and then submitting excessive change orders to recoup additional money, but in this instance heed Don's advice before you do that. You may not legally have that option.
Re: Grocery store service
I agree with MARKETMAN. Having audited a lot of retail stores including grocerys -- 15 tons A/C is realistic but the resistance heat load could be greater. These places often have cooking and a lot of refrigeration plus water heating. 600 amp service is reasonable. Need to do calculations and meet code requirements.Besure your bid lists the customer electrical equipment to be served and statement that upgrades per NEC requirements for additional customer equipment to be customer's responsibility. Otherwise let it go. Flashworks.com has a good simple sizing program which I have found usefull but you still have to know ALL the equipment loads
I agree with MARKETMAN. Having audited a lot of retail stores including grocerys -- 15 tons A/C is realistic but the resistance heat load could be greater. These places often have cooking and a lot of refrigeration plus water heating. 600 amp service is reasonable. Need to do calculations and meet code requirements.Besure your bid lists the customer electrical equipment to be served and statement that upgrades per NEC requirements for additional customer equipment to be customer's responsibility. Otherwise let it go. Flashworks.com has a good simple sizing program which I have found usefull but you still have to know ALL the equipment loads
Re: Grocery store service
hey there,DB work is good if you can get it..
If you are sole sub on this project then sit with Builder and owner and get their equipment list and design only to that, state clearly what you will provide list all exclusions.
good luck but you are shooting in the dark without the basic Equipment in order to perform basic load calcs... If that is not enough you can always pullout Means and go to the back and Wag on their Cost per sf on a similar structure.
hey there,DB work is good if you can get it..
If you are sole sub on this project then sit with Builder and owner and get their equipment list and design only to that, state clearly what you will provide list all exclusions.
good luck but you are shooting in the dark without the basic Equipment in order to perform basic load calcs... If that is not enough you can always pullout Means and go to the back and Wag on their Cost per sf on a similar structure.
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