backup system

The backup system momentarily came to life, and then it too went down.

They couldn't simply shut off the power, because there was certainly some kind of backup system in the place.

And a backup system that is supposed to take over within minutes did not do so for more than an hour.

The light was restored at first by the use of a backup system.

There were always plenty of backup systems in case something should go wrong.

At that point, the backup electrical system had been out of service for more than a year.

But probably the best criterion is the value of the data for which the backup system will provide insurance.

A second team was going to try to fix the backup system.

On the other hand there could be a backup system that we hadn't discovered.

But I've never known the backup system to be off at the same time.