10-Second Start: A Look at NFPA 110 and Time to Readiness Following Power Loss

NFPA 110 defines “Type” as the maximum time, in seconds, that the emergency power supply system will permit the load terminals of the transfer switch to be without acceptable power

Type 10, therefore, has a 10-second time to readiness: meaning that a source of electrical power of required capacity, reliability, and quality must be provided to life safety loads within 10 seconds following loss or failure of the normal power supply.

The ability to start a unit, bring it up to acceptable frequency and voltage and then connect it to a facility suffering from an outage makes engine-based generator sets the standby power system of choice for these facilities. But what happens in those critical 10 seconds? When does the clock start and stop? What is acceptable power?

These questions generate much discussion for technical and nontechnical manufacturers, installers and end-users alike. Recently, Mike Sanford, a Technical Marketing Specialist at Cummins, led a course for the 2019 Minnesota Fire Marshal Conference in Eagan, Minnesota. Fire marshals and inspectors - who are responsible for approving emergency power system installations - and other fire department leaders completed the course to enhance their understanding of NFPA 110, key aspects that affect the equipment selection/design and strategies for ensuring generator set starting performance and reliability.

Here are some additional resources on NFPA 110 Time to Readiness:

Visit the webinar archive to replay the Feb. 2019 NFPA 110 Time to Readiness webinar or download the presentation.

Visit the white paper library to view or download the 10-Second Time to Readiness White Paper.