Controller Sat for 14 Months…Won’t Run…
Posted on 28. Jan, 2010 by Admin in Blog, Product Support.
I love getting these calls, mainly because we offer free support for the life of all of our equipment. And yes this means the old stuff from the 1910’s-1920’s. This controller, not so old, 1997 was a VVVF NEMA 4X Control System mounted in a Purged Cabinet for Class 1, Division 2 locations. The job site was an oil refinery.
The mechanic called letting me know that the controller was not running and hadn’t been for 14 months. After asking what inputs on the PLC were lit up he indicated he provided me the point numbers, which I was able to pull the original file and determine that the following were connected and working.
- SAFE - Safe to Run
- AUTO – Automatic Operation
- DOOR ZONE – Elevator at a Floor
- TSD – Top Slow Down Switch – Elevator At Top Floor
The missing two items that were preventing the elevator from running were the DGL and RCI Inputs.
- DGL – Door Gate Limit Contact
- RCI – Retiring Cam Circuit.
With the both front and rear doors closed DGL was not lighting up. Without this contact RCI would never pick and allow the elevator to run. With the retiring cam down as well the door lock contact was not made up.
Remember, free support goes a long way. I’m glad that the PLC wasn’t burned up and am happy that we were able to assist. Toll free support is something we’ve always provided and for all of our equipment.
***WARNING: Only licensed elevator technicians are to work on elevator and escalator equipment. If you do not knowwhat you’re doing you will seriously injure or kill someone or yourself! Elevators are EXTREMELY DANGEROUS! ****
