Arc flash damages battery cabinet at Cyxtera data centre in Waltham

What happened

On 14 February 2023, firefighters were called to an electrical equipment fire at a Cyxtera data centre in Waltham, Massachusetts. An explosion and arc flash in a battery cabinet damaged that cabinet and adjacent cabinets when panels were blown off. Smoke detectors and the fire alarm operated. Fire services evacuated the building, had power shut down, and ventilated the premises after hazardous levels of carbon monoxide and hydrogen cyanide were found. One person was taken to hospital with possible smoke inhalation. The building was reported undamaged, and fire services later allowed operations to resume the same day.

Contributing factors

The fire department report states that the cause is undetermined. Investigators considered it most likely that an unspecified electrical event tripped a breaker under load, after which generator power automatically back-fed the main breaker and caused it to arc and burn inside the cabinet. Work on another electrical service in the same room was reported as appearing unrelated.

Lessons learned

1. Check that standby generators cannot back-feed a breaker that has tripped under fault, and test that protection.
2. Keep the recorded cause open when investigators say it is undetermined, even if a most-likely electrical sequence is described.
3. Do not allow re-entry until ventilation has reduced carbon monoxide and hydrogen cyanide after a battery-cabinet arc event.

Source

datacenterdynamics.com