Trane Engineered Smoke Control System Application Manual page 125

Communication watchdog
Figure 62. Watchdog communication relationship between a system
MP581 and the central FSCP control MP581
Figure 63. Sample TGP showing transmitting during watchdog
communication process]
Figure 64. Sample TGP showing watchdog signal receive process
There are three communication signals used in the smoke control system:
BCU to MP581, MP581 to MP581, and MP581 to EX-2. The status of all
three communication types needs to be indicated at the smoke control
panel. Each MP581 collects communication status information from the
connected BCU and its associated EX-2 modules and transmits the status
back to the smoke control panel MP581. A custom binding, MP580-1/
nvoSwitch39 to MP580-2/nviSwitch37, is used to send the collected status
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