Case Studies

Chiller Starter Failure Threatens Client’s 24/7 Facility

A federal government customer experienced an issue with the starter for a critical chiller that could have threatened operations at a facility that operates 24 hours a day, seven days a week.

The customer had been troubleshooting the problem for days to no avail. Their frustration was at a very high level by the time they called in Potomac Testing Inc.’s technicians to investigate the faulty starter. While performing testing specified by the InterNational Electrical Testing Association (NETA), our field engineer specialist discovered irregularities with the autotransformer winding resistance. Reduced voltage starter systems use an autotransformer to adjust the voltage during starting. PTI located a replacement autotransformer, assisted with installation and retested the unit. PTI also recommended operating changes to the customer which would alleviate some of the issues they had experienced with the unit. After one long day, they had the chiller running as designed, and the customer had regained faith in their system.

All PTI technicians are NETA certified, receive periodic product (relay, switchgear, controls, etc.)training and understand equipment operations so they can provide recommendations and repair solutions. These individuals are also trained in the requirements of NFPA 70E (Standard for Electrical Safety in the Workplace) and can conduct the tests in a safe manner and with complete knowledge of the hazards involved.

 

Major Transportation Hub Goes Dark

Project Name:

Major Transportation Hub Goes Dark

Description:

Potomac was able to replace a transformer within 48 hours to get this station fully back online. While the lead time would normally be at least several months for a replacement transformer, Potomac has the resources to quickly locate and procure used equipment, performing any necessary modifications to ensure the electrical distribution equipment will operate to the required specifications.

Regular Maintenance Prevents Major Outage

Project Name:

Regular Maintenance Prevents Major Outage

Description:

While performing scheduled maintenance at a military installation, Potomac technicians discovered insulation that was compromised, apparently due to the improper assembly of equipment. As a result, safety equipment was not properly in place and the 13,000 volt switchgear was in imminent danger of failure. This failure could have led to an explosion that would have damaged additional equipment and possibly weeks of downtime. Potomac was able to perform repairs within 24 hours with very little downtime.

Federal Facility Back Online within a Week

Project Name:

Federal Facility Back Online within a Week

Description:

The remnants of a hurricane dumped over 5 inches of rain on the nation’s capital. An underground river flooded several critical agencies downtown. Potomac received an emergency call when it was clear GSA was overwhelmed and needed additional support fast. The flooding was so severe, that one facility’s 65×20’basement was now 10 feet deep – fully submerging their switchgear.  Potomac Testing crews worked around the clock to pump the water out, assess damage and completely rebuild every element of the 13,000 volt switchgear including 18 circuit breakers, instrumentation, metering, and protection. Temperature and humidity control were critical in this government facility. Potomac was able to get the first section back online within a week so that air handlers, chillers, dehumidifiers were fully back in operation. Potomac was quickly asked to handle an adjacent flooded government facility as a result of this fast, successful work.