Feeder Calculation- Track Lighting

[Fred Bay]

If track lighting is being used as the sole means of general lighting within a retail store, is it acceptable to calculate the feeder based on 150 VA per two feet of tract + 125% for continuous duty, and not include an additional minimum 3 VA per square foot for general lighting?

It seems the 3 VA per square foot is required as a minimum for general lighting if the actual general lighting installation is unknown, or turns out to be less than 3 VA per square foot.

After calculating the length of track proposed on this project at 150 VA per two feet of track, the installed lighting will exceed 3 VA per square foot. The general lighting for the store is provided solely by the track lighting. Is there a need to add the minimum 3 VA per square foot for general lighting to the feeder calculation at this point?

Also, can the 200 VA per foot required for show windows cover track lighting installed at the show windows. Show window receptacles are being provided per code.

 

[bob]

If track lighting is being used as the sole means of general lighting within a retail store, is it acceptable to calculate the feeder based on 150 VA per two feet of tract + 125% for continuous duty, and not include an additional minimum 3 VA per square foot for general lighting?

It seems the 3 VA per square foot is required as a minimum for general lighting if the actual general lighting installation is unknown, or turns out to be less than 3 VA per square foot.

After calculating the length of track proposed on this project at 150 VA per two feet of track, the installed lighting will exceed 3 VA per square foot. The general lighting for the store is provided solely by the track lighting. Is there a need to add the minimum 3 VA per square foot for general lighting to the feeder calculation at this point?

Also, can the 200 VA per foot required for show windows cover track lighting installed at the show windows. Show window receptacles are being provided per code.

If the actual lighting load is greater that the minimum load from table 220.12,
then you would use the actual. Look at example D3 in Annex D and the note at the bottom of the caculation.

 

[nakulak]

if you have plans, don't they show the actual number of track heads ?(ie can' you just calculate the exact lighting load rather than use the per foot of track ?)

 

[steve66]

if you have plans, don't they show the actual number of track heads ?(ie can' you just calculate the exact lighting load rather than use the per foot of track ?)

According to the NEC, you have to base the feeder and service sizes on the length of track that is installed.

I think this is because it is so easy for anyone to add more lights to a track.

However, for some reason, the NEC doesn't require the branch circuits to be sized the same way. I assume that they feel an overloaded branch circuit will only trip the branch breaker.

Steve

 

[BLUEDEVIL]

if the tracklighting is greater than 3va/sf you can use the actual track lighting load and you do not need to add 3va/sf....for show window it is the same use the greater load

 

[Fred Bay]

Thanks for the help. Nice to have the feedback.

-Fred Bay