Setup menu > alarm levels – Hochiki FIRElink-400CM User Manual
Page 17

FIRElink-400 Air Sampling System – Installation Manual
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© 2010 Hochiki Europe (UK) Ltd
9-5-0-346/ISS4/OCT10
1.1.1 Alarm Levels (Numeric – Address 001-127)
Setup Menu > Alarm levels
The value set in the Pre Alarm level , Fire 1 level and Aux level functions in the Alarm levels submenu is
the relatively scaled bargraph level at which the appropriate alarm is initiated on the detector. The Fire 2
level function assigns an absolutely scaled alarm level in % obs/m to the Fire 2 alarm. The Aux level is
set by factory default at level 10 which means that this alarm will occur after the Fire 1 alarm.
1.1.1 Alarm Delays (Numeric - Address 001-127)
Setup Menu > Alarm levels
The alarm delay is the number of seconds that an alarm level has to be continuously sensed before the
alarm is initiated. Each alarm level has a programmable delay of between 0 and 90 seconds.
1.1.1 ClassiFire® Override (Numeric - Address 001-127)
Setup Menu > Alarm levels
When this function is set to a value other than zero, the shorting together of one of the "Input 3" contacts
on the detector main circuit board by means of volt free contacts will desensitise the detector by moving
the alarm levels out by the specified percentage.
1.1.1 ClassiFire® Alarm Factor (Numeric - Address 001-127)
Setup Menu > Alarm levels
The detector sensitivity is set with this entry, which will also affect the probability of nuisance alarms. 0 =
high sensitivity/higher probability, 8 = low sensitivity/lower probability.
NOTE: The highest sensitivity setting is suitable for clean, environmentally controlled environments, for
example, semiconductor manufacturing clean rooms where airborne pollutants are kept to an
absolute minimum and the least contamination is cause for alarm.
Use of this setting in a busy machine shop would lead to relatively frequent nuisance alarms due
to the normal variation of atmospheric contamination and a lower sensitivity setting is
recommended. It is therefore important that the alarm factor chosen is suitable for the area to be
protected. When the appropriate alarm factor for the protected area has been set, nuisance
alarms will be reduced to an absolute minimum.
The following table gives suggested settings of ClassiFire alarm setting for different locations:
Alarm
Factor
Sensitivity
Probability of Nuisance
Alarm
Suggested Protected Area
0
Extremely High
Once per year
Semiconductor manufacturing clean room
1
Once per 5 years
Computer Room
2
Once per 10 years
Non-Smoking Office
3
Once per 50 years
Clean Factory
4
Medium
Once per 1000 years
Warehouse
5
Medium
Once per 5,000 years
Warehouse with diesel trucks operating
6
Medium
Once per 10,000 years
Warehouse with diesel trucks operating