SAN FRANCISCO (CBS SF) – BART officials have deployed a new high-tech tool in their attempt to identify the source of an electrical spike that is damaging passenger cars and has forced the temporary shutdown of regular service between the North Concord and Pittsburgh/Bay Point stations.

BART spokeswoman Alicia Trost said the new tool was installed Monday on a test train engineers are running along the troubled section to detect what is causing the electrical surge in the third rail that has knocked more than 50 passenger cars out of service.

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“We bought a new tool yesterday,” she told KPIX 5. “We put it on the test train. The new tool can measure things (electrical current) at a much more granular level providing the finite information that we need because what we know is the spike is occurring so quick – we are talking about 100th of a millisecond — and the instruments we had before weren’t picking it up.”

Trost did not disclose what the new tool cost, but said it will “help solve the problem.”

The test train, which is carrying riders, was first deployed Sunday night and marks the first train cars moving between the two stations since service was halted by a problem reported around 10 a.m. Wednesday.

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Besides giving engineers an idea of how train cars are operating between the two stations, the test train is supplementing bus trips during rush hour. Service between the two stations returns to a bus bridge in the off-peak hours.

“What this shows is we have figured out how to run one train without it being damaged,” she said.

Trost said BART officials unsuccessfully tried to add a second train on Monday.

“Yesterday, we did try to add a second train into the loop (between the two impacted stations), but we experienced propulsion problems,” she said. “It showed us we were overloading the system. The draw was just too much for two trains. It gave us a glimpse of what we can handle and what we can’t (on the line).”

Trost said on a daily basis 12,000 commuters are transported by BART between the North Concord and Pittsburg/Bay Point stations.

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