LV under cab recessed puck lights

[FVC electric]

I have 10 recessed puck lights @ 20w each. They are wired with 2 tranformers rated at 150w each. I'm using m/c cable for the class 2 wiring. In NYC romex is not permitted. My question is do I need to provide fusing for the class 2 wiring to the puck lights? Thank you,

 

[Dennis Alwon]

I don't believe fusing is necessary but how are you connecting the mc to the puck lights?

 

[FVC electric]

The recessed puck lights fit snug into the holes drilled into the wood. If you pull the light down you will see that I spliced the m/c to the wire tails that are on the fixture. I will use wire nuts and tie wraps so when you pull the fixture out the splice won't come apart. No boxes do to the small areas where the fixtures are.

 

[kwired]

If it is a class 2 circuit supplied by a class 2 power supply it does not need overcurrent protection it will be inherently protected in the power supply.

If it is not a class 2 circuit it must still be a listed system - I have not seen a listed system yet that does not have overcurrent protection included with the power supply - most likely a requirement for the listing.

How are you connecting the luminaires to the MC cable? That is likely a problem.

 

[FVC electric]

I will use a red head and a single m/c connector with no box. A box will not fit in the recessed hole for the fixtures. It is low voltage.

 

[kwired]

I will use a red head and a single m/c connector with no box. A box will not fit in the recessed hole for the fixtures. It is low voltage.

How does that comply with 411.5(D)?

(D) Insulated Conductors. Exposed insulated secondary circuit conductors shall be of the type, and installed as, described in (1), (2), or (3):
(1) Class 2 cable supplied by a Class 2 power source and installed in accordance with Parts I and III of Article 725.
(2) Conductors, cord, or cable of the listed system and installed not less than 2.1 m (7 ft) above the finished floor unless the system is specifically listed for a lower installation height.
(3) Wiring methods described in Chapter 3

MC is a wiring method described in chapter 3 but your description of how you wish to terminate this is not mentioned anyplace that I am aware of in chapter 3.

Voltage is not the issue with low voltage lighting, current and heat are.

A fully loaded 150 watt 12 volt transformer is putting out 12.5 amps of current. Although the risk of shock is reduced by the lower voltage we still must follow chapter 3 rules because a weak conductor junction point will still heat up whether is is supplied by 480 volts or 12 volts. At the luminaire is the worst possible place for connections also - you have the heat from the lamp contributing to it already.

 

[FVC electric]

How does that comply with 411.5(D)?


MC is a wiring method described in chapter 3 but your description of how you wish to terminate this is not mentioned anyplace that I am aware of in chapter 3.

Voltage is not the issue with low voltage lighting, current and heat are.

A fully loaded 150 watt 12 volt transformer is putting out 12.5 amps of current. Although the risk of shock is reduced by the lower voltage we still must follow chapter 3 rules because a weak conductor junction point will still heat up whether is is supplied by 480 volts or 12 volts. At the luminaire is the worst possible place for connections also - you have the heat from the lamp contributing to it already.

I have a single m/c tail to each fixture. The load will be 1.66 amps. The only connection not in a box is at the fixtures. All others will be installed in accordance with chapter 3. I wish I could use a box for the fixture connection but there is no room. Its very tight. Wish there was a correct way to install puck lights but the is not. I only like to do things the right way...ugh.

 

[kwired]

I have a single m/c tail to each fixture. The load will be 1.66 amps. The only connection not in a box is at the fixtures. All others will be installed in accordance with chapter 3. I wish I could use a box for the fixture connection but there is no room. Its very tight. Wish there was a correct way to install puck lights but the is not. I only like to do things the right way...ugh.

I don't like puck lights as there is no real good way to install them that is code compliant and also looks good.

All of the ones I have ever seen have a cord attached to them that plugs into the power supply or a cord from the power supply. If you do not use this you are not installing it correctly no matter how much you dislike the cord and plug on the product this is what is the proper install requires using.