Investigation of Spikes in Voltage on Pittsburg/Bay Point Line Continues

April 17, 2016
On April 2nd, normal train service resumed between Pittsburg/Bay Point and North Concord/Martinez.
Normal service resumes

On April 2nd, normal train service resumed between Pittsburg/Bay Point and North Concord/Martinez.

After swapping out the generation of train cars most prone to damage (BART's "C" cars) to help establish regular service again, the spikes in voltage along the track has gone away. BART has since moved the C cars back to add more cars to the line, and the problem has not reoccurred.

"The problem has gone away," said Paul Oversier, assistant general manager of operations, "but we need to get to the bottom of this.  We don't want our customers to suffer through another round of this so we need to get to the root cause."

Investigation into root cause continues

The team looking into the cause of the spikes in voltage in this area is methodically identifying all possibilities and then testing each theory during service as a process of elimination. This is in addition to nationally recognized outside experts who have been using state-of-the art instrumentation to diagnose what technical experts term "extreme voltage transients."

"We've instrumented a car to measure the voltage at different locations and even put cameras underneath the car body to focus on the collector shoe to see if we are getting inordinate amounts of arcing as the collector shoes go through gaps," Oversier explains. "We are also focusing on the propulsion box to see whether the arcing was originating there. We have another theory of ionized air which is a conductor. If you have ionized air, it could be a possible source of the arcing we were seeing. So, we have been doing air sampling alongside of a moving train to see if there is ionized air."

New experts join investigation

BART now has a company coming in from the outside that aren't so much technical experts on electrical systems or cars as we have already engaged expertise in those areas. These are process experts on problem-solving. They are going to take our data and look at it from yet another angle with a different set of eyes.

No safety concern for riders

There's no safety risk or concern for riders traveling over an area that is being assessed for voltage spikes, because the voltage spikes may not even be noticeable to them. 

Repairing damaged cars

While one team focuses on finding and fixing the electrical problems, technicians in BART shops are working round the clock to repair the damaged cars as quickly as safely possible. 

A new Fleet of the Future is on the way to bring some relief to crowded cars, however, other infrastructure needs such as replacing old rails, updating train control equipment, expanding maintenance facilities and rebuilding other parts of the system must be dealt with as well.