Otis 411 AC Drive

I'm trying to track down any AC drive information for an Otis 411. It was taken by a previous contractor and we are have drive issues. Our latest fault was a M421? We are in the midst of a major modernization and are trying to keep the freight running as we move forward. Anything will help, thank you.

m421 isnt a fault number its telling you to use the service tool and go to module-4-2-1 to see the fault. must be a good sales guy to mod a 411 with a a/c drive. thats still new equipment.

Isn't a 411 a dc drive for dc machine. otis here(aus) used a 311 control for an ac machine. Maybe we dont get all models here.

e411 with a ovf428 drive would be my guess

Gp when you say e411 your referring to elevonic control?

The building was modded with Otis equipment in 2003 and shutdown on 2005. The consultant on the project specified non-proprietary controls so here we are. Everything was stolen from the site so we just want some drive info for both the AC and DC drives while we are mod everything else.