Low Voltage Track Lighing

[lizzie14]

I've read 411 and 410 and can't seem to find any description on load sizing for low voltage track lighting OTHER than 250W/2ft. If I know the track head wattage, do I still have to use 250W?

 

[DetroitEE]

Did you mean 150W/2 ft? 220.43(B)

 

[lizzie14]

uh huh. i meant 150w. is that the going rate or can i got with the transformer rating??

 

[DetroitEE]

I just use the 150W/2 ft per code (unless I know the actual load will be greater). Perhaps the intent of this is to allow for additional track heads to be added in the future, even if you know there will only be 50W every two feet when it is designed. Even if that's not the code's intent, I think its good design practice to go by the 150W number.

Anyone know if there's another code section that would allow you to use the xfmr rating for calculating the load for track lighting?

 

[Dennis Alwon]

Well I have nothing to back this up but if this is low voltage and a single circuit track then I would use 300 watts for my calculation no matter what the length is since there is no single circuit track that can be wired more than 300 watts. All the 600 and 900 watt trans are set up for 2 or 3 circuits.

I may be wrong on this but that is what I would lean toward knowing the likelihood of anything more than 300 is not realistic.