I ran into an interesting situation:
We received a machine that had three single phase transformers mounted next to each other on the floor of the panel with a metal stud coming up through the middle of each. A steel flat bar with a hole for each stud held all three transformers down.
The transformers were wired together to go from 220 Delta to 380 Wye. Upon appying power we began to see smoke within seconds. The transformers were not hot but the studs holding them down were.
There were no shorts on the transformers, the transformers were wired correctly, they were isolated from the metal by rubber, and upon removing the clamp bar, the problem went away.
My coworker suggested magnetism was causing the heat. Any ideas?
I have attached a sketch of the layout if I have been unclear.
We received a machine that had three single phase transformers mounted next to each other on the floor of the panel with a metal stud coming up through the middle of each. A steel flat bar with a hole for each stud held all three transformers down.
The transformers were wired together to go from 220 Delta to 380 Wye. Upon appying power we began to see smoke within seconds. The transformers were not hot but the studs holding them down were.
There were no shorts on the transformers, the transformers were wired correctly, they were isolated from the metal by rubber, and upon removing the clamp bar, the problem went away.
My coworker suggested magnetism was causing the heat. Any ideas?
I have attached a sketch of the layout if I have been unclear.