Siemens MXL-IQ, Руководство по эксплуатации, установке и обслуживанию

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M-2
Appendix M
Dual Criteria Logic Functions
The CSG-M provides a logic function type
labeled Criteria Selection. The following
inputs to this function are a detector’s:
• pre-alarm (from IL devices or
Analaser),
• verification, or
• chamber or thermal for the photo
thermal detector (ILPT-1)
Pre-alarm and chamber or thermal selec-
tions cannot be mixed in the same function.
The output can be any that is capable of
being driven by output logic, including
sending the output to another function.
Note: For networked MXL-IQ systems, no
external panel inputs are allowed in
the Criteria Selection function.
MXL-IQ Pre-alarm
Software
Pre-alarm Learning and Setting
The MXL-IQ automatic pre-alarm learning
feature adjusts smoke detector pre-alarm
levels (during the time period selected in
the CSG-M) until they stabilize. Depending
upon pre-alarm activity, the system starts
with the most sensitive pre-alarm level and
gradually adjusts (de-sensitizes) the
MXL-IQ until pre-alarms no longer occur.
The level reached by each smoke detector
at the end of the learning period is the
learned pre-alarm level. No pre-alarms
annunciate or feed output logic during this
learning period.
The learned pre-alarm level is stored in
flash memory so that on a panel power-on,
watchdog, or nickel reset, the pre-alarm
readings still exist. When a new or modi-
fied CSG-M is loaded into flash memory,
the MXL-IQ will NOT assume pre-alarm
existed before and will re-start the
learning mode.
The flash memory used for storing pre-
alarm detector readings shares the intelli-
gent environmental control (IEC) flash
memory area. This requires that a boot
block flash device be used if pre-alarm is
enabled. The flash segment size shared by
IEC and pre-alarm is 8K. Each IEC device
uses 2 bytes and each pre-alarm device
uses 1 byte, allowing a maximum of slightly
over 2500 devices with both IEC and pre-
alarm.
Manual pre-alarm settings can be set at the
MXL-IQ by using the CONTROL PER-
CENT/FT PRE_ALARM command (See
Pre-alarm and Sensitivity Settings below).
Any valid pre-alarm reading within the
range specified in the table on page M-3
can be used. Pre-alarm adjustments are in
%/ft obscuration. Manual settings override
the learning mode settings. However, they
do not take effect until the end of the
learning period.
Pre-alarm Event Annunciation
Annunciation is a global yes/no option and
the type of annunciation is a trouble. The
trouble report contains the type field text of
Pre-alarm and both the INs and OUTs are
recorded. The format of these trouble
reports is identical to the format of all
existing MXL-IQ trouble or supervisory
reports.
Annunciation of a pre-alarm smoke detec-
tor is provided even if the device goes
immediately into alarm. The alarm is
reported first because of its higher priority,
but a pre-alarm or trouble is also generated
thereafter with the same time and date.
Output logic control using the criteria
function with ILI/ILP pre-alarm as the
criteria selection follows the INs and OUTs.
If latching is desired, it must be added in
the CSG-M. Using the criteria selection
function to select either the chamber or the
thermal for the ILPT-1 takes the MXL-IQ an
additional 5 seconds (or more) to evaluate
after the device alarms. This occurs
because a special status poll must be done
to determine whether it was the chamber or
the thermal that caused the alarm. A
criteria function with a selection of alarm
verification provides an output for the
duration a smoke detector is being verified
or until reset if the device alarms.
Pre-alarm and Sensitivity Settings
Pre-alarm and sensitivity adjustments are in
%/ft obscuration and have the following
ranges, increments, and default values: