kestrel
Member
- Location
- New Brunswick, Canada
I am bidding a job and the spec calls for 4 250 KCM aluminum conductors (plus #6 Grnd) in 2 1/2" pipe or MC cable with rubber sheath (we use TECK cable a lot in Canada with is MC with a rubber sheath on the outside).
The complete run is through a building (school) running approximately 200 ft going through 4 cinder block support walls (core drill required). From the electrical room to the end of the run there will be approximately 6 90 deg turns and several changes in elevation (offsets will be required). About 110' of the run is through ceiling space with a tile ceiling (2x4 ceiling tiles) with some areas being quite tight with the other stuff run in the ceiling (eg. plumbing, data, power, etc.). The remainder of the run is surface mounted (about 30' on one end at the electrical room, and 60' on the other end going to the 3 phase 120/208 sub-panel. I have attached a drawing of the run and you will notice the area in the tiled ceiling is outlined in a yellow box (the cable run is the red arrows).
The 4C 250KCM MC cable itself has an outside diameter of approx 2.4" and 200 ft of MC weighs around 500 lbs.
My thinking is that because of the size and the weight of the MC cable and the fact that we probably cannot run from one end to the other and will probably have to start somewhere in the middle.
I would rather use the MC because normally the labour to run + the materials is a lot less than piping + materials.
To avoid damage to the ceiling tiles and T-bar frame I think I would have to use pulley blocks setup every 10 ft or so to keep the heavy MC off the T-bar frame.
Does anyone have experience running MC cable in this type of situation? Is is feasible or should I plan to use pipe?
Thanks in advance.
Attila
The complete run is through a building (school) running approximately 200 ft going through 4 cinder block support walls (core drill required). From the electrical room to the end of the run there will be approximately 6 90 deg turns and several changes in elevation (offsets will be required). About 110' of the run is through ceiling space with a tile ceiling (2x4 ceiling tiles) with some areas being quite tight with the other stuff run in the ceiling (eg. plumbing, data, power, etc.). The remainder of the run is surface mounted (about 30' on one end at the electrical room, and 60' on the other end going to the 3 phase 120/208 sub-panel. I have attached a drawing of the run and you will notice the area in the tiled ceiling is outlined in a yellow box (the cable run is the red arrows).
The 4C 250KCM MC cable itself has an outside diameter of approx 2.4" and 200 ft of MC weighs around 500 lbs.
My thinking is that because of the size and the weight of the MC cable and the fact that we probably cannot run from one end to the other and will probably have to start somewhere in the middle.
I would rather use the MC because normally the labour to run + the materials is a lot less than piping + materials.
To avoid damage to the ceiling tiles and T-bar frame I think I would have to use pulley blocks setup every 10 ft or so to keep the heavy MC off the T-bar frame.
Does anyone have experience running MC cable in this type of situation? Is is feasible or should I plan to use pipe?
Thanks in advance.
Attila