Control Engineering

The Inevitable Failure Occurs
August 6, 2007

In my March 28th entry I discussed the inability of the City to obtain spare parts for the remaining 38 existing RTU controllers being used to regulate level in key pumping stations. We mentioned that if an RTU failure occurred at a station it would need to be manually operated until an emergency controller replacement from another manufacturer could be designed, built and installed.

Got a call today from the city maintenance person responsible for maintaining these controllers, asking for emergency assistance with one. The three pump station is down to one pump that comes on and off only via a low level lockout circuit, thus controlling through a span of only .3 feet in the wet well (ie. cycling severely). Obviously, with a substantial rain the station won't be able to keep up with only one pump. We were informed by the caller that available support for these obsolete RTUs is down to one fellow and a retired guy who sometimes can fix things on the side. We had to tell the city's maintenance person we believed it was unlikely we could help them fix this RTU. We suggested he pursue whatever support remains for the RTU and if this is unsuccessful, we'll help him retrofit another controller into this application that he has in stock and that he has support for.

Corresponded with the primary consultant's lead project engineer this past week regarding getting together for a planning meeting - vacation schedules have interfered. Planning on a conference call with he and his SCADA guy this week.

Posted by on August 6, 2007 | Comments (0)