It comes to economics. A WO is issued to reconnect a service upgrade. Unless it specically says replace the tri-plex, they won't. If someone made the effort in the field and it was not on the WO, someone will be "on the carpet" for it. New construction they typically carry a couple of sizes of wire and no one on the POCO side will take the time to crunch any numbers. It is the sparkies installation that usually throws the peception off. We have a 200 amp service with either 2/0, 3/0, or a 4/0 cable hanging out for the POCO to connect to. How often does residential service draws enough power to require such a size? 99.999% of the time, never. In theory the service will never reach it's demand level let alone maxing the service out.
Look at a electric stove circuit for example. A 12kW stove has only a 8kw ciruit and when was the last time the breaker tripped on it?
The POCO's takes advantage of the demand load on the service. Partly to save cost on wire and to minimize strain on the anchors holding the tri-plex at both end.
Last edited by sparkyinak; 04/09/08 11:16 AM.
