LED lighting and table 220.12

[Strathead]

I pondered an interesting thought this morning.

In my area they are retrofitting a huge indoor sports facility with all LED lighting. I had heard that another phase of the project was to replace the entire distribution system and they were calculating a reduction in size due to the new lighting. Hence my pondering.

With the huge advent of energy saving lighting which is surely not going to go back the other way, isn't 220.12 obsolete? Can the distribution system of a big lighting load be reduced by some sort of engineering exception when the customer is paying for permanent installation of very expensive but reduced energy LED lighting?

 

[mwm1752]

Which occupany in table 220.12 would you use for an indoor sports facility? Seems to me you would apply 220.14(D). Just curious have you calculated a watts per foot for the existing lighting and the proposed. I always thought table 220.12 was a pretty minimum figure to use. As for the service would you replace & reduce existing lateral? that would seem odd. Reducing the buss size to new calcs IMO could be a choice made within the regulations of the NEC.

 

[Strathead]

Which occupany in table 220.12 would you use for an indoor sports facility? Seems to me you would apply 220.14(D). Just curious have you calculated a watts per foot for the existing lighting and the proposed. I always thought table 220.12 was a pretty minimum figure to use. As for the service would you replace & reduce existing lateral? that would seem odd. Reducing the buss size to new calcs IMO could be a choice made within the regulations of the NEC.

I think you are dwelling on the least important part of the question. What if I had said an office complex, or a bank, etc? But, I would classify the sports facility as an auditorium, as it is a basketball arena specifically. But that was merely an example of what got me thinking.

 

[Dennis Alwon]

With the advent of LED I think there are many things in the NEC as well as in the field that are obsolete. In many areas the energy code requires energy efficient bulbs yet many manufacturers make there fixtures (especially recessed cans) with markings for incandescent bulbs and not led. The problem is that as long as there are incandescent bulbs available then those fixtures must be calculated by the largest sized bulb available. I think eventually that may not be an issue but for now it is what it is.

 

[iwire]

Can the distribution system of a big lighting load be reduced by some sort of engineering exception when the customer is paying for permanent installation of very expensive but reduced energy LED lighting?

Typically the new lighting is rated / listed at a much lower wattage so I am not seeing the issue.

The only time it comes up is say when say someone is trying to do new work using an 150 watt incandescent fixture with a 30 watt LED. in that case they are stuck with the 150 watt rating. A better choice would be a 30 watt rated LED fixture.

 

[don_resqcapt19]

Typically the new lighting is rated / listed at a much lower wattage so I am not seeing the issue.
...

I don't understand how the actual type of lighting that is to be used enters into this. You still have to size the service per the rules in Article 220.

 

[Dennis Alwon]

I don't understand how the actual type of lighting that is to be used enters into this. You still have to size the service per the rules in Article 220.

I think this is more of a branch circuit issue

 

[tom baker]

Washington allows us to size lighting loads per the energy code which is far less than the NEC.

 

[mjf]

With the advent of LED I think there are many things in the NEC as well as in the field that are obsolete. In many areas the energy code requires energy efficient bulbs yet many manufacturers make there fixtures (especially recessed cans) with markings for incandescent bulbs and not led. The problem is that as long as there are incandescent bulbs available then those fixtures must be calculated by the largest sized bulb available. I think eventually that may not be an issue but for now it is what it is.

As far as the recessed cans go, it's too bad I can't find a LED recessed can for equal to or less than the cost of a standard can with an LED retrofit.

 

[PetrosA]

As far as the recessed cans go, it's too bad I can't find a LED recessed can for equal to or less than the cost of a standard can with an LED retrofit.

And I don't understand why we're not seeing LED specific cans that would be able to take a variety of lamps from different manufacturers. In the EU most LED lamps are sold with a GU24 base as are luminaires nowadays like many of our energy efficient surface mount lights that accept CFL only lamps. If they at least sold LED/CFL only cans with ratings for those lamps, we would have a lot more leeway in how we sized circuits and dimmers for them.

 

[Strathead]

I think this is more of a branch circuit issue

I am with Don on this and that is why I wrote this question. I wasn't even referring to retrofit of incandescent cans and branch circuits. Regardless of the actual wattage of the lighting, you must still size your service using table 220.12

 

[mwm1752]

I pondered an interesting thought this morning.

In my area they are retrofitting a huge indoor sports facility with all LED lighting. I had heard that another phase of the project was to replace the entire distribution system and they were calculating a reduction in size due to the new lighting. Hence my pondering.

With the huge advent of energy saving lighting which is surely not going to go back the other way, isn't 220.12 obsolete? Can the distribution system of a big lighting load be reduced by some sort of engineering exception when the customer is paying for permanent installation of very expensive but reduced energy LED lighting?

Since I don't read minds, " they are retrofitting" you must have meant replacing lamps only -- "a huge indoor sports facility" or any other type of occupancy per your response to my ealier comments -- "replace the entire distribution system" sounds extravegant -- "due to the new lighting" Still replacing lamps only? -- "huge advent of energy saving lighting" not convinced you are replacing lamps only -- "which is surely not going to go back the other way" sounds permanent/irreversable -- " Can the distribution system of a big lighting load be reduced by some sort of engineering exception when the customer is paying for permanent installation of very expensive but reduced energy LED lighting? yes, you have permanently/irreversable reduce the load calculation for the structure

 

[Strathead]

Since I don't read minds, " they are retrofitting" you must have meant replacing lamps only -- "a huge indoor sports facility" or any other type of occupancy per your response to my ealier comments -- "replace the entire distribution system" sounds extravegant -- "due to the new lighting" Still replacing lamps only? -- "huge advent of energy saving lighting" not convinced you are replacing lamps only -- "which is surely not going to go back the other way" sounds permanent/irreversable -- " Can the distribution system of a big lighting load be reduced by some sort of engineering exception when the customer is paying for permanent installation of very expensive but reduced energy LED lighting? yes, you have permanently/irreversable reduce the load calculation for the structure

Sorry your assumptions are incorrect. This is a huge $60 million dollar remodel. All lighting is being replaced. My contention is that table 220.12 "shall constitute the minimum" load required to be used for feeder calculation. Since there are many places where the code allows "engineering supervision" and this isn't one of them I contend that with a literal translation there is not allowance to reduce the load without specific exception by the State when adopting the code.

 

[iwire]

Typically the new lighting is rated / listed at a much lower wattage so I am not seeing the issue.

I don't understand how the actual type of lighting that is to be used enters into this. You still have to size the service per the rules in Article 220.

Don,

The type and wattage matters greatly.

If the final goal of a new lighting design is to use say a 15 watt LED choosing an incandescent fixture with a 150 watt listed rating and screwing in 15 watt LRD retrofit into it is the wrong way to go.

Just use a 15 watt LED fixture and the load calculation issues go away.

In the case of a true retrofit situation the circuits and distribution are already in place so I really do not understand what Strathead is trying to get at. :huh:

 

[Strathead]

Don,

The type and wattage matters greatly.

If the final goal of a new lighting design is to use say a 15 watt LED choosing an incandescent fixture with a 150 watt listed rating and screwing in 15 watt LRD retrofit into it is the wrong way to go.

Just use a 15 watt LED fixture and the load calculation issues go away.

In the case of a true retrofit situation the circuits and distribution are already in place so I really do not understand what Strathead is trying to get at. :huh:

I indicated that the actual situation that got me thinking about this generic question was a remodel where they were doing an entire new distribution system as well as lighting and were going to reduce the size of the distribution. Now, the load calculation issues don't just go away. In order to calculate the size of the service required, you must use table 220.12 which is based on the type of structure providing a fixed wattage per square foot minimum.

 

[mwm1752]

Since I am always confused I'll put this out -- I am assuming you are not in 2014 code cause ---- the exception to 220.12
Exception: Where the building is designed and constructed to comply with an energy code adopted by the local authority, the lighting load shall be permitted to be calculated at the values specified in the energy code where the following conditions are met:
(1) A power monitoring system is installed that will provide continuous information regarding the total general lighting load of the building.
(2) The power monitoring system will be set with alarm values to alert the building owner or manager if the lighting load exceeds the values set by the energy code.
(3) The demand factors specified in 220.42 are not applied to the general lighting load.

refers to energy codes, which are in effect with the altering of lighting over 50% of the existing lighting - If the AHU has adopted the energy codes. sooo, there is an option to 220.12 under certain circumstances. watts per sq ft for a particular occupancy would not apply

 

[don_resqcapt19]

Don,

The type and wattage matters greatly.

If the final goal of a new lighting design is to use say a 15 watt LED choosing an incandescent fixture with a 150 watt listed rating and screwing in 15 watt LRD retrofit into it is the wrong way to go.

Just use a 15 watt LED fixture and the load calculation issues go away.

In the case of a true retrofit situation the circuits and distribution are already in place so I really do not understand what Strathead is trying to get at. :huh:

The service and feeder load calculations are based on the rules in Article 220. They do not change based on the type of lighting you install. You can play around with the branch circuits, but not the feeder or service load calculations.