Page 6 P/N: 22066P
© 2004 Bosch
DS240/DS241 Installation Instructions
7.3 Fine Tune Alignment
• Connect the supplied TC2000 Test Cable to Pins 1, 2 and 3 of
P6, the group of pins located just to the right of the receiver’s
terminal strip (see
Figure 14).
Figure 14 - TC2000 Connection
- Temporarily disconnect the Remote Indicator Plate connector, if
installed.
• Connect a 20,000 Ohm/volt (or greater) DC VOM to the black
(–) and red (+) leads of the TC2000.
- Set meter scale so that readings of 0.0 to 5.0 VDC can be
read.
• Check the three LEDs on the receiver.
- If the beam is being received by the receiver, the green LED
should be flashing, and the red and yellow LEDs should be on
steady.
- If the green LED is on steady, the beam is not reaching the
receiver. If this is the case, the preliminary alignment proce-
dure should be attempted again.
• Observe the meter readings and adjust the receiver’s optical
module using the Horizontal and Vertical Fine Tuning adjustment
screws for a maximum reading on the meter. This is the most
critical process of alignment. For the most effective operation
of this system, the peak voltage during fine tune alignment
must be obtained.
NOTE: When performing fine tune alignment, keep arms and hands
away from the front of the receiver and out of the beam path.
• The maximum voltage peaked reading will vary depending on the
distance between the transmitter and receiver. The acceptable
peaked voltage range is 0.50 to 5.00 V. The voltage at the
receiver is greater at shorter distances. It is very important to
peak the voltage to insure a stable trouble free detector.
Hint:
Make a note of the alignment voltage. It may be helpful if
future troubleshooting is necessary.
• After completing the fine tune alignment, remove the test cable,
then replace and secure the receiver's cover.
• Check the status of the receiver’s green LED. It should still be
flashing.
• With the meter still connected to the test cable, re-install the test
cable to P6 through the opening in the cover (red lead towards
center of unit).
• An alarm test may be performed here if desired by connecting
the white and black wires of the TC2000. To reset the unit,
temporarily remove power.
• Press the receiver’s Set-up button located just below the P6/test
cable connection (see
Figure 15). Press only if the covers are
on both transmitter and receiver.
- This starts a one to two minute automatic internal setup
process that results in a reference voltage for measuring
beam blockages.
Setup
Button
LEDs
Figure 15 - The Receiver's Set-up Button
- The red and yellow LEDs should turn off, and the green LED
will turn on steady. After some voltage fluctuations, the meter
should settle at 5.0 VDC.
NOTE: Be careful not to block the beam or move the units during
this time.
- At the end of the setup period, the receiver’s green LED will
flash, and the voltage will drop to between 3.8 and 4.2 VDC.
This is a reference voltage that later readings can be com-
pared to when determining the need for cleaning.
• If the voltage is not between 3.8 VDC and 4.2 VDC, push the Set-
up button again.
• After set-up is complete, remove the test cable (and reconnect
the Remote Indicator Plate connector if used).
• Replace and secure the access door.
8.0
Other Information
8.1 Fire Alarm Reset
To reset the receiver after a fire alarm has occurred, remove power
from the receiver for at least one second, then re-apply (see also,
Section 8.4 Power Outage on page 7).
8.2 Cleaning
At least once a year, the outside of the covers should be cleaned with
a common window cleaner and a soft, clean cloth. Under normal
conditions, this should not result in a trouble alarm as long as the
beam is not continuously blocked for more than 18 sec. After cleaning,
recheck the reference voltage. If the voltage is less than 3.8 VDC, or
greater than 4.2 VDC, calibrate the units (see
Section 8.3 Reference
Voltage Calibration).
8.3 Reference Voltage Calibration
The reference voltage of the detectors should be checked at least
once a year (or more often if required by local regulations or authorities
having jurisdiction). Clean covers are necessary for proper
reference voltage readings.
