Thousands of homes lost power after residents in Clydebank reported hearing a "boom" on Wednesday afternoon.
Clydebank police said they received calls about the noise and SP Energy Networks confirmed a fault was reported around 4.40pm.
Most customers had power restored within five minutes but about 300 others in the Duntocher area in particular were without power until 5.38pm.
A spokesman for the utility firm said: “We had a fault at Klibowie substation at around 4.40pm Wednesday afternoon.
"Initially, a few thousand homes may have experienced some form of power interruption. However, a large portion of these customers were reconnected by 4.45pm.
"Engineers quickly responded to the fault, and all homes had power restored by 5.38pm. We apologise for any inconvenience caused, we worked hard to restore supplies as quickly as possible.”
Residents told the Post they heard the boom in old Mill Road and Cornmill Court.
One resident told us: "I was in my veranda in Hardgate and I heard an almighty bang! Then seconds later there were alarms going off everywhere.
"It was some noise! Never heard anything like it."
The fire service said they attended the substation in the area but there was no fire.
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