I General
A conventional fire alarm system usually depends on a resistor at the end of the loop to keep
its normal operation, inappropriate matching will lead to abnormal operation of the whole
system, even result in problems like nuisance alarm. Matching with multi-wire fire alarm
controller or intelligent zone monitor unit, P-9907 Active End of Line Unit (hereinafter called
the unit) takes the place of terminal resistor and solves the above problem, thus increases
reliability of conventional fire alarm system.
II Features
1.
Zone two-bus, simple and convenient for mounting and wiring.
2.
Fault alarm for removal of detectors.
3.
Can be used as the base, sparing space.
4.
Stable and reliable performance.
5. Anti-interruption
ability.
III Technical
Specifications
1. Operating
Voltage:
Power Bus Voltage: DC24V Range Allowed: DC15V
DC28V
2. Operating
Current
5mA
3.
Equivalent Resistance: 4.7K
4.
Wiring: Zone two-bus, polarized
5. Operating
Environment:
Temperature: -10
~+50
Relative Humidity
95%, no condensation
6. Dimension: 103mm
37.4mm
7.
Material and Color of Enclosure: ABS, ivory white
8.
Weight: 88g
9.
Mounting Hole Distance: 60mm
IV Structure and Operation Principle
1.
The bottom is shown in Fig.1.
2. Operation
Principle
The unit is installed at the end of zone loop composed of multi-wire fire alarm controller or
intelligent zone monitor unit. When multi-wire fire alarm controller or intelligent zone monitor
unit is powered up and in normal operation, the unit is acting as a load to produce periodic
plus-minus alternating differential pulse signals. Due to the voltage dividing of current
limiting resistor, the filtered power voltage is reduced, the system is in normal operation state.
When the detector is removed, a diode is put in the loop and changes plus-minus pulse to
one-way pulse, reducing the load of the unit and increasing the power voltage after dividing
and filtering. The multi-wire fire alarm controller or intelligent zone monitor unit can judge
fault signal according to this. The judging method of short or broken circuit of zone loop is
similar with the above method.
The unit, matching with multi-wire fire alarm controller or intelligent zone monitor unit, can not
only keep normal operation of conventional fire alarm system, but also alarm fault (without
affecting fire alarm by other field devices) when removing detectors, alarm fault on open
circuit and alarm fire on short circuit, etc.
V
Mounting and Wiring
Warning: Before installing the device, disconnect the power from the loop and verify
that all bases are securely installed and that the wiring polarity is correct at each base.
The mounting method of the unit is the same as that of detector base, there are two wiring
mode:
1.
When the unit is used as a detector base, a conventional detector can be mounted on it.
Connect the anode of zone loop to terminal "1" and cathode to terminal "3" as shown in
Fig. 2.
P-9907 Active End of Line Unit
Installation and Operation Manual
(Issue 2.0, March 2003)
Fig. 1 Bottom
