Ragin Cajun
Senior Member
- Location
- Upstate S.C.
My latest design project will have one of these.
My client managed to get his hands on a used Square D I-Line panelboard lineup. From Square D delivery would be well over a year. He will get his in January of the coming year! The shop providing the equipment had been around over 50 years and knows what they are doing. The only negative is I would have ordered one with a cable entry section like I used on previous projects. This one is set up for cable entry behind the main breaker. The bus bars are barely 24” from the floor! Any way you look at it the electrician will need ape arms. My concern is that the likelihood of conductor and primarily insulation damage trying to bend and shape large cables to connect to the bus.
Reference the photo of similar gear.
Originally, I was going to use 10 – 600 MCM per phase with a 3/0 neural. But, coming out of 10 - 3-1/2” PVC conduits from below will be a nightmare. At best, with all the different phases crisscrossing each other, avoiding damage to the insulation will be unlikely. And maintaining equal phase conductor length? HA! The service transformer is a pad mount that is only 20 feet away.
One night when I couldn’t get to sleep, I think I came up with what I thing is a workable solution! How about using 12 - 500 MCM in 3-1/2” PVC conduits and coming up out of the floor directly under the phase bus bars, each conduit with only it’s respective phase conductors! Minimal bending of the conductors to lay onto the bus above. Little chance of damage and no crisscrossing. And maintaining equal phase lengths possible. Each conduit would have 4 – 500 MCM same phase conductors.
The system 3/0 neutrals would be in their own 3 – 3-1/2” PVC conduits and terminate to the neutral bus.
Of course, NO ferrous metal ever between the separated phase conductors!
Thoughts?
My client managed to get his hands on a used Square D I-Line panelboard lineup. From Square D delivery would be well over a year. He will get his in January of the coming year! The shop providing the equipment had been around over 50 years and knows what they are doing. The only negative is I would have ordered one with a cable entry section like I used on previous projects. This one is set up for cable entry behind the main breaker. The bus bars are barely 24” from the floor! Any way you look at it the electrician will need ape arms. My concern is that the likelihood of conductor and primarily insulation damage trying to bend and shape large cables to connect to the bus.
Reference the photo of similar gear.
Originally, I was going to use 10 – 600 MCM per phase with a 3/0 neural. But, coming out of 10 - 3-1/2” PVC conduits from below will be a nightmare. At best, with all the different phases crisscrossing each other, avoiding damage to the insulation will be unlikely. And maintaining equal phase conductor length? HA! The service transformer is a pad mount that is only 20 feet away.
One night when I couldn’t get to sleep, I think I came up with what I thing is a workable solution! How about using 12 - 500 MCM in 3-1/2” PVC conduits and coming up out of the floor directly under the phase bus bars, each conduit with only it’s respective phase conductors! Minimal bending of the conductors to lay onto the bus above. Little chance of damage and no crisscrossing. And maintaining equal phase lengths possible. Each conduit would have 4 – 500 MCM same phase conductors.
The system 3/0 neutrals would be in their own 3 – 3-1/2” PVC conduits and terminate to the neutral bus.
Of course, NO ferrous metal ever between the separated phase conductors!
Thoughts?
