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ZONESENSE DH4
OPERATORS MANUAL
5.3
Outputs – Supervised “Alarm” (TB3) & Unsupervised
“Door Holder” (TB801)
The Main Control Card has two (2) parallel PTC protected supervised outputs (TB3) typically used to
power electronic type sounders referred to as alarm outputs and two (2) parallel PTC protected un-
supervised outputs (TB801) used to power door holders and referred to as the door holder outputs.
Each output is nominally rated at 250mA @ 24VDC.
Supervision is achieved by the sensing of the End of Line (EOL) 10k
Ω
resistors and is independent
of the loading of bells and sounders. The supervision is forward biased and requires diodes to be
fitted in series with each bell and sounder. Faults on the supervised outputs will be indicated by the
FACP within 60sec.
The Supervised Alarm Outputs (TB3) are activated by the:
Class change input
Alert input
Front panel evacuate control, silence/resound control
Zones entering the alarm condition. If there are no delays programmed the alarm outputs will
be activated within 3 seconds of the zone entering the alarm condition.
5 6 7 8
TB3
+ -
1 2 3 4
TB801
+ -
+ -
+ -
Alarms O/P's
Door Holder O/P's
Bell
Note: If a diode is NOT fitted
internally to the Bell / Sounder a
diode MUST be fitted as
shown - fit 1N4004 or similar
EOL
10K
Ohms
Sounder
EOL
10K
Ohms
Figure 8: Alarm Output Wiring
Note:
If a diode is NOT fitted internally to the Sounder a diode MUST be fitted as shown above
The Unsupervised Door Holder 1 and Door Holder 2 Outputs (TB801) are;
Normally energised and
De-energised on a Fire condition, evacuate condition and mains fail condition. There is a
small de-bounce time (approx 5 seconds) for mains fail, so the door holder outputs are not
de-energised on a power glitch.
