Trane Engineered Smoke Control System Application Manual page 116

Chapter 7 Programming
104
From requirements 33.2.1 and 33.2.2, we can see that there is a
decoupling between annunciation and reaction. The series of network
variables shown in Figure 54, nvoSwitch05 through nvoSwitch12, are
used to directly control the smoke alarm LEDs on the FSCP. For example,
a smoke alarm for floor 1 is received. The mechanical system reacts by
pressurizing floor 2 and exhausting floor 1. Following that, floor 2 goes
into smoke alarm. The alarm needs to be annunciated even though the
mechanical system does not react. In this case, nvoSwitch06 passes the
smoke alarm state to MP580-3 by using a custom binding. At MP580-3,
the binary output that controls the floor 2 smoke alarm LED is turned on.
BAS-APG001-EN