What signals does the GDS need to transmit to the fire alarm system?
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As the title suggests, there’s another question: isn’t the gas detection and alarm controller something different from a GDS?
GB-50493 requires a secondary alarm signal for combustible gases and a fault signal for the GDS alarm control unit
Is the secondary alarm signal generally sent to the fire alarm system? Is the fault signal hard-wired?
Are they all hardwired? If there are many sensors at the site, won’t that require many wires for the secondary alarm signals?
To connect a hard wire from the GDS to the fire alarm system, just one set of wires is sufficient. As long as there is a gauge in the GDS for combustible gases that has a secondary alarm function, the signal from that gauge will trigger an alarm; not every gauge’s secondary alarm signal is sent to the fire alarm system.
5.1.2 The second-level alarm signals for combustible gases and the fault signals from the alarm control unit shall be sent to the fire control room for graphical display and alarm. Combustible gas detectors cannot be connected directly to the input circuit of a fire alarm controller.
Is it to create an interlock logic in the GDS and then output a digital signal to the fire alarm?
It may vary from one GDS manufacturer to another, but in the end it is the GDS that outputs a digital signal to the fire alarm