Home Forums General Discussion Technical Questions Armor TMS 900

Got a gearless high rise Armor car that has an intermittent oscillation problem when leveling into the floor (sometimes pretty violent, shakes the entire machine room floor). It will act up mostly running from 16 to 17. The machine, deflector sheave (pulled and bearings replaced), drive, tachs (both tachs replaced, Thyristors, SCR's... just about everything has been double and triple checked and/or replaced (what parts we could get). Any ideas?

Sounds like one of the three current transformers may have an internal loose connection.

We checked those with a scope then swapped them out with a different car. We did find a shorted AC choke and had it repaired.