Honeywell Vertex M Technical Handbook page 47

Vertex M 24-Point Continuous Monitor
TM
Section 3 - Startup
1st TWA Time
Use to set times for the beginning and end of each 8-hour, Time Weighted Average (TWA)
period. Use this option to associate the TWA periods with shifts or any other regular event.
The system calculates and displays the TWA after each 8-hour TWA cycle.
The default setting is 04:00 indicating that the Vertex M will run three successive TWA
periods from 04:00 to 11:59, 12:00 to 19:59, 20:00 to 03:59. Remember, the Vertex M
System uses a 24-hour clock. For example, to set the first TWA to 3:00 P.M., enter 15:00.
If you view the profile information for this example, you will see the TWA End At Time is
07:00/15:00/23:00. The system automatically sets the beginning times of the second and
third TWA periods at 8-hour intervals from the time entered for the first TWA period.
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