Bus Freeze Thaw Effects – Oregon, USA

Foster SubstationBackground

The Foster Substation, located near Hermiston, Oregon, is constantly exposed to year-round severe weather.

After a review from the Umatilla Electric Cooperative (UEC), seven vertical locations on the 1-½” Bus were found to be cracked due to freeze/thaw effects.

Damaged Bus TerminalsWelding vertical Bus connections in rain and mild wind conditions would have been especially difficult and required the services of an outside contractor. With 10 days to repair these connections, UEC turned to DMC Power to deliver:

• (7) 1-½” Bus Splices - PLK1000D24A

• (7) 1-½” Offset Bus Terminals - PLK1880D24A

• 1-½" Swage Tooling (DLT58MAPW000)

SolutionReplacement Bus Terminal Installation

To prevent future freeze/thaw occurrences, the DMC Power engineering department modified our existing Offset Bus Terminals to include a weep hole. After customer approval the order was immediately processed and our manufacturing team went to work.

10 days later DMC Power representatives arrived on site with the connectors and Swage tooling required.

The construction crew was brand new to Swaging and allotted three days of total outage time after delivery of the connectors. Within 30 minutes DMC Power had the crew fully trained and ready to Swage.


Replacement Bus Terminal and SplicesAll connectors were installed, inspected and the substation was back in service before lunch on the very first day. UEC was able to use their own crews instead of a specialized welder, saving two full outage days and the cost of the outside contractor.

“DMC POWER was able to ship us the connectors in less than 10 days and provided onsite training.  The installation was extremely fast and we were able to re-energize the substation the same day” 

• Crew Member – Umatilla Electric Co-Operative

(Click to enlarge gallery images)