I came up with an issue the other day that I thought I would get an opinion on.
On the property of a dwelling unit the owner has a detached garage. Feeding the garage is a 12/2 UF cable that runs into a switch box at the door. The 12/2 is fed from the panel in the home. The 12/2 feeds all lights and receps in the structure. Coming back out of the switch box is a 12/3 UF cable that runs back to the house to feed a 3-way switch. Basically you can switch the garage light on or off from the house or the garage. So, you have two runs of wire from the house to the garage.
The owner has requested that he would like to put an electric unit heater in the garage now. After looking at the options, trying to get additional power to the structure will be difficult. (Asphalt driveway and sidewalks). My thought was to Demo the 12/3 UF cable from the switch and making it into the feed for the electric unit heater; fully understanding that this is not nearly as convient as switching the garage light from two locations. After digging around in Art. 225 it would appear that if this were done, the installation would now not be code compliant. Art 225.30 says I can only feed with one branch ckt or feeder. So in my thought, I would be feeding the structure with two branch ckts now. This would not be code compliant. Also, I was always thought that if you feed a garage with one 20-amp single pole ckt that had equipment ground accompanying it, you need not drive a ground rod or have any form of disconnect. Even if I were to use both the 12/2 and 12/3 as branch ckts, I would need a disconnect on the outside of the building, or closest point on the inside. Any thoughts or words of wisdom would be very welcome!
Thanks
On the property of a dwelling unit the owner has a detached garage. Feeding the garage is a 12/2 UF cable that runs into a switch box at the door. The 12/2 is fed from the panel in the home. The 12/2 feeds all lights and receps in the structure. Coming back out of the switch box is a 12/3 UF cable that runs back to the house to feed a 3-way switch. Basically you can switch the garage light on or off from the house or the garage. So, you have two runs of wire from the house to the garage.
The owner has requested that he would like to put an electric unit heater in the garage now. After looking at the options, trying to get additional power to the structure will be difficult. (Asphalt driveway and sidewalks). My thought was to Demo the 12/3 UF cable from the switch and making it into the feed for the electric unit heater; fully understanding that this is not nearly as convient as switching the garage light from two locations. After digging around in Art. 225 it would appear that if this were done, the installation would now not be code compliant. Art 225.30 says I can only feed with one branch ckt or feeder. So in my thought, I would be feeding the structure with two branch ckts now. This would not be code compliant. Also, I was always thought that if you feed a garage with one 20-amp single pole ckt that had equipment ground accompanying it, you need not drive a ground rod or have any form of disconnect. Even if I were to use both the 12/2 and 12/3 as branch ckts, I would need a disconnect on the outside of the building, or closest point on the inside. Any thoughts or words of wisdom would be very welcome!
Thanks
