Confirming Installation

[moresi]

I am running a 100 amp 3 phase 120 / 208Y sub panel for a commercial kitchen off of a 225 amp 120 / 208Y main panel. I am supplying 2 - 208 volt 40 amp ranges, 1 208 volt 30 amp water heater, and 6 120 volt 20 amp circuits. What if anything should I be concerned with as far as proper distribution of my circuits in the panel? Am I setting myself up for an unbalanced condition?

 

[celtic]

Did you leave room for the shunt trips?

 

[hurk27]

I would be doing a load calculation on the main service:roll:

and if they are using both ranges maxed (like most restaurants do) I think the sub panel will be over loaded.

if these are single phase ranges, one range phase A to B, second range B to C, water heater C to A, the 6 receptacles just two on each phase.

 

[hurk27]

Did you leave room for the shunt trips?

Just shunt trip the whole panel from the feeder breaker, we do this all the time.

If he puts all the two pole breakers on one side and the single poles on the other, it would be already balanced as best you can do.

I take back about the sub panel being over loaded, but it will be close depending upon what they use those plugs for

 

[iMuse97]

Just shunt trip the whole panel from the feeder breaker, we do this all the time.

If he puts all the two pole breakers on one side and the single poles on the other, it would be already balanced as best you can do.

I take back about the sub panel being over loaded, but it will be close depending upon what they use those plugs for

as you implied: recept's in a commercial kitchen can get very heavy use. I'd still do the load calc. of possible configurations/installation scenarios, based on what they suppose they will use this for, and considering that a busy restaurant will be adding equipment not now planned for.

 

[celtic]

Just shunt trip the whole panel from the feeder breaker, we do this all the time.

No doubt....might then require a sub-panel for everything not under the hood.
Who knows?

 

[moresi]

I should provide more information.

The kitchen is going to be used by a small non-profit agency that prepares approximately 40 prepackaged meals / day for elderly individuals. All food is baked in ovens and we have been approved by AHJ to not have to install vent hood and ANSUL system. There will be no frying or grease producing vapors. The electric ranges are both resi. grade but yes, will be operated at same time. They are not 3 phase - single phase only. There will be 2 resi grade fridges and a chest freezer as well as small dishwasher and disposal. A few counter outlets for small counter spaces. The entire kitchen is approximately 350 sq./ft. Main panel in building only feeds 120v. loads - There are no three phase loads in building presently. There were in it's former life.
Vent hoods are 100 cfm range hoods.

So am I correct in that I just load the 2 pole loads appropriately on the new three phase panel distributing them as evenly as possible.

Appreciate all the feedback.

 

[celtic]

So am I correct in that I just load the 2 pole loads appropriately on the new three phase panel distributing them as evenly as possible.

I don't think there is another option.....but someone may produce one.

 

[LarryFine]

if these are single phase ranges, one range phase A to B, second range B to C, water heater C to A, the 6 receptacles just two on each phase.

If he puts all the two pole breakers on one side and the single poles on the other, it would be already balanced as best you can do.

This is exactly what I would do.

 

[moresi]

I now have updated information regarding this installation. Was at the site today and here is what I have. The building has all updated wiring and prior to this small kitchen being installed it was used for industrial purposes. In this kitchen space there are 3 sets of 4 wire #6 THHN from the main 3 phase panel piped to a large pull box. I intend to use some of these conductors for the 2 electric ranges - 3 conductors for each 208 v. range. I now only need 8 120 volt 20 amp lines for remainder of kitchen circuits. I am planning on installing a small main lug 12 space three phase panel in this space to serve these 120 volt loads. I plan to use 4 of the remaining #6 thhn conductors direct from the panel piped to this new panel on a 60 amp breaker. I did my calcs. and come up with a toal load of 34 amps per phase for my necessary 20 amp circuits. This will leave me some room for future circuits and I am able to evenly distribute the loads on the phases. I will have the electric water heater on a dedicated circuit off the main 225 amp panel. Thoughts? Seem feasible / proper? There will be no future growth of this kitchen space and it is only for the preparation of packaged meals for elderly residents.

 

[LarryFine]

Thoughts? Seem feasible / proper?

Works for me!