What would the proper protective gear be for residential distribution panel work?
In this area the meter could be pulled so the panel isn't live, but meters are rarely pulled. In other areas the POCO doesn't want ECs to pull meters. In either case with a live panel the top of the main is "Live POCO" which is somewhat close to unfused.
I'm curious what kind of arc flash could happen if the main shorted and what kind of PPE would be required for protection in that circumstance.
Dave, With an un-fused supply, you are basically at the mercy of the Secondary side of the Transformer feeding the Installation. Considering the lack of fusing, I would get Cover-up gear around the main, depending upon what you were doing. Other way you could do it is with Insulated Gloves and Protectors and Isolate your Phases by Insulating them with the Main Switch turned off and then remove them and Insulate them. Other side of the coin too, wear a face shield, in case something does go wrong.
If we would apply the Canadian code rules, this would not be as big of a problem as long as you are not trying to work on the line side connections. Their code requires an additional cover over the line side connections that remains in place while working on the load side parts. Without this cover, you will need arc flash PPE. This would often require the use of an arc flash hood as well as FR clothing. Don
The videos I've seen of a short in a meter bank in a metering room for a condo or some other type of big building is truly impressive. It's something you do not want to be near.
The required PPE would be, for my companies, FR shirt, natural fiber clothes, steel toes, Class 0 gloves, hard hat, and safety glasses and/or face shield.
Depending on the power company's high-side protection is certainly taking a large gamble with your life. Its scheme is designed to protect equipment, not people. OH transformers would be more merciful than UG equipment since those Bay-o-net fuses are way over sized to force the pothead fuse to blow first.
Also when it comes to pulling the meter, don't do it unless the power company specifically says it's okay. Cutting the seal is usually the first step to "diverting current." Most power comapnies are pretty serious about that stuff.
We had an electrical contractor (David Emmerling, with Wigdahl Electrical Company of Elk Grove Village, IL) and Deputy Chief Wayne Luecht of a FD south of us get burned (3rd degree - 93%) when a fault two miles away decided to use the panel room housing 480v gear in a shopping center as a "point of release".
The contractor was KIA - Chief Luecht died after 11 days in CCU. The building engineer survived, and underwent therapy.
[This message has been edited by DougW (edited 08-28-2005).]