I retensioned the hoist ropes today to make sure nothing changed. The customer recently told me they were moving office furniture all week before this happened.

The drive indicates the speed and it shows car is overspeeding and underspeeding back and forth. I compared this with the other car for accuracy.

Even with ropes retensioned on inspect and sometimes 350fpm i was almost feeling slip. Ropes are all sitting equally in their grooves on the drive sheave....I marked the ropes and after 15-20 runs they had moved equally up the sheave. Ropes are still within spec and were replaced in 2004.