Siemens MXL-IQ Operation, Installation, And Maintenance Manual page 160

Appendix L
Basic Two Stage System
L-6
Complex Two Stage System
The figure on the next page demonstrates a
more complex Two Stage system. The
basic principles of operation are the same
as the basic Two Stage system with a slight
variation.
In this example, several Two Stage control
functions are used in the system design.
Together with the proper glue logic, a
modified Two Stage system is the result. In
this system, the floors above and below the
alarm signal Stage 1 coded audibles while
the floor of alarm codes Stage 2 audibles.
The general differences between the basic
and complex systems are as follows:
• The first alarm will result in Stage 1
coding on that floor.
• An activation of a keyswitch will place
the system in second stage. There-
fore, the floors above and below the
alarm will code Stage 1; Stage 2 will
code on the floor of alarm.
• If an adjacent floor generates an
alarm, that floor will code Stage 2.
This same principle may be applied to
networked MXL-IQs using external refer-
ences.
For example: The building in alarm codes
Stage 2 while the adjacent buildings code
Stage 1.
Visual indications are made using MOD-16
outputs. Simply connect the signal in the
logic diagram to the desired LED or other
function to indicate the system stage.
For example: Connect Stage 1 and Stage
2 inputs to an LED function to indicate the
system state.
NOTE: Since other audibles may be
present in the system besides coded (Two
Stage) audibles, the AUDIBLE SILENCE
LED on the MKB will indicate the state of
the AUDIBLE SILENCE flag as usual. Its
state will only change with manual interven-
tion (manual silence/unsilence).
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