Bosch DS484Q Installation Instructions Manual page 4

DS484Q/DS486Q | Installation Instructions | 1.0
1.3.6 Selectable AND/OR Gate
The photoelectric intrusion detection system in the
DS484Q and DS486Q provides alarm relay activation
for different considerations. Use the DIP Switches to
select the required protection:
AND gate – All four beams must be blocked
simultaneously to cause an alarm. This setting results in
fewer false alarms caused by birds and other small
animals.
OR gate – Either the upper or lower pairs of beams
must be blocked. This setting can detect an intruder
crawling on the ground.
1.3.7 Environmental Discrimination Circuit (EDC)
The Environmental Discrimination Circuit (EDC)
sends a signal when maintaining stable operation
becomes difficult due to environmental disturbances.
The EDC detects the gradual loss of signal along the
beam's path because of dirt built up on the cover, or
because of rain, fog, or snow. If the signal decreases by
95% over at least 4-seconds, the EDC activates the
EDC LED (refer to Figure 3 on page 3) and relay. This
indicates that something is partially blocking a beam,
or that the covers need cleaning.
The EDC feature was not evaluated by
Underwriters Laboratories (UL).
Figure 4: Receiver DIP Switches
1
1 - DIP switches 1through 4 and 6 in the OFF
position
2 - DIP Switch 5 (EDC BYPASS Switch) in the
ON position
To use the EDC Bypass Switch, set the receiver's DIP
Switch 5 to ON or OFF (Figure 4). Refer to Table 1 for
information about the functions and detector status.
Connect the EDC to a trouble circuit.
Check the system after the EDC relay
activates.
4
Overview
2
Table 1: EDC BYPASS Switch States
Detector Status BYPASS Switch
OFF
Poor EDC LED lights
Environmental and EDC signal
Condition* is provided
through the
normally-closed
relay output at
the receiver.
The alarm is
generated by loss
of beam energy.
When either EDC LED turns
optical module is on and EDC
blocked for 3 or signal is provided
more seconds.
No alarm output
is generated.
When both After the
optical modules specified
are blocked for 3 interruption time,
seconds. the ALARM LED
turns ON and
alarm signal is
generated.
If beams are
blocked for more
than 3 seconds,
EDC LED turns
ON, and EDC
signal is
generated.
∗
Poor environmental condition refers to difficulty in maintaining
stable operation due to environmental disturbances like fog or
rain.
Bosch Security Systems, Inc. | 7/05 | 4998138530F
BYPASS Switch
ON
EDC LED turns
on and EDC
signal is provided
through the
normally-closed
relay output at
the receiver.
With the loss of
beam energy, the
ALARM LED
lights but alarm
signal is not
generated (alarm
relay is
automatically
shunted).
EDC LED turns
on and EDC
signal is
provided.
If another optical
module is
blocked, the
ALARM LED
turns ON, but no
alarm signal is
generated.
After the
specified
interruption time,
the ALARM LED
turns ON, and
alarm signal is
generated.
EDC LED does
not turn ON, and
EDC signal is not
provided.