Many years ago I was called to an office building where there were strange noises coming from the ceiling cavity. I heard the noise and got a look into the area and there were four GRS conduits containing the service conductors with a phase and neutral each in separate conduits. Some of the u-bolts securing the conduit to the steel trusses had broken and I actually witnessed the conduit moving and they were HOT! I called the owner, fire department, POCO, and the local inspector. The building was condemned until changes were made to correct the problem. The wire size was adequate but the separate conduits were the culprit.
Rowdy
