hhsting
Senior Member
- Location
- Glen bunie, md, us
- Occupation
- Junior plan reviewer
Attached picture the red rectangle marked between utility meter and main breaker are they typically bus or cables?
Main service switchboard
- Thread starter hhsting
- Start date
- Location
- New Jersey
- Occupation
- Journeyman Electrician (retired)
Can't really read the writing since the photo qualtiy is poor. If its all one peice of equipment that may be bolted together then busbars.
hhsting
Senior Member
- Location
- Glen bunie, md, us
- Occupation
- Junior plan reviewer
- Location
- New Jersey
- Occupation
- Journeyman Electrician (retired)
IMO 99.9% bus.Attach is little better pic.
ModbusMan
Senior Member
- Location
- Cleveland, OH
- Occupation
- Building Automation Engineer
Agreed... all our drawings specifically call out number and size of wires when they exist.
hhsting
Senior Member
- Location
- Glen bunie, md, us
- Occupation
- Junior plan reviewer
Where would the service entrance conductors be then in case like this?
Deltaforce
Senior Member
- Location
- India
- Occupation
- Electrical Engineer
Busbar trunking involved?
ModbusMan
Senior Member
- Location
- Cleveland, OH
- Occupation
- Building Automation Engineer
The engineering firm our GC uses will include this on the one-line
Tucked down in the corner is the legend to specify wire types:
2500 - 6 sets 3 600kcmil and 1 350kcmil ground
2502 - 6 sets 4 600kcmil
The busbar sizes inside the switchgear weren't specified on the drawings I peeked at. I would imagine they're either on the submittal drawings, or perhaps incorporated as part of the UL listing.
hhsting
Senior Member
- Location
- Glen bunie, md, us
- Occupation
- Junior plan reviewer
Engineer is saying all wire into switchboard are electric utility. Then where would the service entrance conductors be? How would one size main bonding jumper?
- Location
- New Jersey
- Occupation
- Journeyman Electrician (retired)
Where is the service point?
ModbusMan
Senior Member
- Location
- Cleveland, OH
- Occupation
- Building Automation Engineer
At least for this site, service point is the step-down transformer (13.2k to 480Y277). You can't see it on the little snip I included, but there are no neutrals until we get almost to the point of use, at which point there's some kind of separately-derived source (Vertiv PDUs for IT gear, and a small-ish Square-D 480 to 208Y120 step-down right in front of the house panels).
kwired
Electron manager
- Location
- NE Nebraska
- Occupation
- EC
Service conductors are whatever lands on the service disconnect. If they are bus bar and not wire type conductors then I believe cross sectional equivalent is used to determine minimum bonding jumper.
- Location
- Illinois
- Occupation
- retired electrician
It would be rare that the utility would provide and install that wire. There would be no service entrance conductors in that case, and Note 2 to Table 250.66 would apply.