Transformer fire at WAPA substation on St. John delays power restoration

What happened

A power transformer at the Water and Power Authority's (WAPA) electrical substation on St. John caught fire and became engulfed in flames during an electrical service interruption. The outage affected St. Thomas, St. John, Water Island and Hassel Island for more than two and a half hours. The transformer, one of two units at the facility, was destroyed. Restoration of power to St. John was further delayed because the substation grounds had to be confirmed safe before personnel could enter, assess smoke damage to the building, inspect switchgear and bus bars, and carry out repairs before reenergising the facility, which receives power via an underwater cable from St. Thomas.

Contributing factors

The fire began during an electrical service interruption; the utility stated a root cause analysis of the burned transformer would be needed to determine the cause, and given the size of the unit this could take several weeks.

Lessons learned

1. A power transformer fire at a substation can destroy the unit and force weeks of root cause analysis before repairs begin.
2. After a transformer fire, operators must confirm substation grounds are safe and inspect switchgear and bus bars before re energising.

More lessons on electrical protection and isolation, from every incident on the register.

Not yet known

• Exact cause of the fire
• Transformer model and age
• Cost of damage and repairs
• Total duration of the outage

This entry is updated when these are reported. Get an alert for the next one like it.

Source

virginislandsdailynews.com