Somebody down in the cellar had pulled the main switch.

One thing more, do you happen to know where the main light switch is situated?

He threw the main switch to cut off the power from all the units, and together we left the laboratory.

Locomotive's main switch must be off when this board is passed.

The first thing we do is find the main switch.

At which moment his fingers found the main light switch.

"I could get to the main switches and shut down everything."

Got to throw the main switch first, and I haven't time to do that now.

He stared at the main switches, and then reached out for them.

Someone in the Hall had had the sense to turn on the main switch.