powerplay
Senior Member
- Location
- In front of a computer.
We are planning to connect two 800amp disconnect switches inside of a steel container to a couple of pole mounted transformers by an overhead mast. Grounding/bonding procedures?
1600amps in an steel container...
- Thread starter powerplay
- Start date
- Status
- Occupation
- Licensed Electrician
No different than any other service. What makes this one special?
powerplay
Senior Member
- Location
- In front of a computer.
I have seen electrical rooms in fire rated rooms made of concrete, cinder block and drywalled wood frame, but never an conductive steel container.
- Occupation
- Licensed Electrician
No worries, it just has to be bonded properly. Most all electrical equipment is contained in a conductive steel container.
petersonra
Senior Member
- Location
- Northern illinois
- Occupation
- engineer
It may be that the steel of the container qulaifies as a GE and needs an appropriate GEC.
- Location
- Massachusetts
powerplay
Senior Member
- Location
- In front of a computer.
It's the Main service that they plan to connect to two pole mounted Transformers for the two 800 Amp Main Disconnects with Voltages of the same characteristics inside this instant "Fireproof" Electrical Room to avoid dealing with building issues. Someone mentioned that they may have to cover the concrete to cover the combustible wood floor...and here I as thinking it would be easier to mount the Disconnects and metering equipment onto an 1" plywood mounted to the container....
powerplay
Senior Member
- Location
- In front of a computer.
Having 2 service drops of same characteristics is not usually permitted, but grouping of switches has been accepted to allow the drop from a second pole mounted transformer. I will be bonding the container door with braided copper line. Fire department wants the switches together. I suppose one could get cramps typing the issues that may come to mind?
powerplay
Senior Member
- Location
- In front of a computer.
What issues are you referring to?
It is rather unusual, as single phase equipment seems to usually be installed up to 1200 amps into Main Switchgear, but to be able to reduce costs on Private Property as well as allow for expansion, some precedence has come into effect. "Grouping" the switches under this circumstance has been accepted, although without stamped engineered drawings, it appears the permit holder is taking a risk even after being passed by Inspectors. The property owner has electrical experience and has consulted people with engineering background to provide appropriate equipment, which I cannot warranty as it is used. I've had an Inspector view the job, but they will not "Design" the job, but came on site and we had opened the Code Book to discuss some issues. He mentioned Separate Containers for Main Disconnnects coming from separate Poles, (there is a private fused cutout switch on the property) but the Fire Department wants it "grouped" for quick response to shutdown. This is why I am open to discussion, as I will have to address issues as they appear with such an large adaptable service that has been accepted in the past, but that which I need to ensure is done right. The Power Authority will need to change fusing on the High Voltage end to allow this much power to the Facility and not adversely affect the areas available power requirements, and have allowed this install with accessible Secondary Metering rather than the expensive Primary Metering they originally suggested... eventually an expensive 3 Phase upgrade is planned, so we do have 800 amp Main Disconnects with 3 phase capability. I love a challenge, but any input to direct my research would be appreciated.
..signed ... " Can of worms" : )
- Status