Technical documentation
20140208BA
AFMS3000
Tel.: +49 (0)4105 / 65 60 – 0 *
DECKMA GmbH
* Fax: +49 (0)4105 / 65 60 – 25
Email:
www.deckma-gmbh.de
Operating instructions
Version 1.0
2018/03/17
page 21 of 24
3.12.
Fault (error)
A fault is an error, which disturbs the proper operation of the system. Parts not affected by the fault
continue to function correctly.
A fault should be remedied as quickly as possible in order to ensure permanent fault-free operation If
the AFMS detects a fault, it reports it.
Supply faults in the power supply can be configured regarding the time (up to max 240 seconds).
Faults in detector telegrams (detector has disappeared) are reported after 60 seconds.
Faults in the internal communication of the assemblies are reported after about 90 seconds.
3.13.
Working principle of sensors (smoke sensor)
Smoke detectors reports once a threshold has been exceeded and then falls below this level again.
The smoke detector itself triggers an interrupt (with ESP telegram), which identifies this (unique)
sensor and displays it. Detectors can be checked regularly with a suitable test gas (or with "real"
smoke). It should be well noted, that not too much of the gas should be used, as residues in the
detector are possible. Also, a detector should not be reset “as quick as possible” (immediately) after a
test procedure, as the detector chamber may not be "clean" again from gas (or smoke) in time (under
some circumstances)! Too early reset will re-trigger a new (maybe unwanted) fire alarm! Wherever a
chamber is "clean" from gas or smoke, and when, cannot be seen from outside and depends only on
the existing air exchange to the detector’s position! Thus, there may be rooms present where no air
exchange takes place and the detector is constantly into this "fog" threshold which then inevitably lead
into a technical error or a PRE-ALARM condition. This is here a “normal function” due to the present
environment.
If a detector reports unusually often alarms, his position is more than unfavorable. A heat detector
(mounted under a hot panel) can be triggered by heat build-up, a smoke detector (over a dishwasher
mounted) will trigger by drops of ‘hot’ water when opening the dishwasher door – same to shower
cabins where the sensor is mounted to close in front of the wet cabin’s door. If a detector triggers
"unintentionally" often, always check the environment as the cause! The HOCHIKI’s failure rate from
sensors are negligible less.
When a detector has triggered, his red alarm LEDs lights up. This is the case with the first five (5)
detectors of each loop! From the 6
th
detector (in chain), no LED will turn on. Each loop can be
unilaterally connected in the event of a fault (loop open), then the load (due to too many LEDs) cannot
become infinitely large. The integrated - and ESP-based - energy management system protects the
loop against possible overload and (as cause of this) against too much voltage drop.
In normal operation (no detector has triggered), a loop current of less than 1mA flows for 127 smoke
detectors! Each pair of red LEDs represents here a much higher load factor for the loop – this must be
avoided. Only in this way can data be transmitted over many kilometers of loop cable at all. Therefore,
the number of LEDs that lights up simultaneously is limited to only five (5). This principle applies to
smoke detectors, heat detectors and manual detectors and affects only the LEDs of the detectors.
