i recently had a 800 hp yk motor on a vsd catch fire
Please explain exactly what burned. What were your megger readings when you performed the last annual inspection? I have seen people start chillers with low megger readings and blow a hole in the windings and shoot a fireball out and leave molten pieces of windings everywhere, but I have never seen one actually catch on fire.
Ditto on bearing failure and all the extra grease pumped in to cover the bearing noise. Fire dept had to put out. Seen lots of windings blow but not go up in flames. Recently a new Trane CVHF had it's VFD catch fire and complely burn up every combustable in machine. Nothing left but copper buss and some wire. Recent York motors are on low end of quality, wouldnt surprise me if they flamed up.
We had same problem on a YK
Wrong greasing procedure used by in house service techs (Big pharmaceutical) wayyyyyy too much grease pumped into the bearings. The motor flamed up. We were not aware of cause of failure until we had the failure report from motor rebuild shop.
Its always a good idea to inspect with flashlight the rotor shaft for indication of grease from bearings. Also, If i remember correctly, York specifies Polyurea based grease such as Mobil Polyrex EM, any other grease is not worthy!!........They say.