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95-8556
2.1
9. Slowly adjust the transmitter module left/right as
required using the horizontal adjustment bolts until
the telescope cross hairs are centered as close as
possible to dead center on the receiver module
window. Tighten the horizontal adjustment bolts and
locking nuts so that no movement will occur.
10. Rotate the telescope alignment tool by 180° and
verify that the cross hairs are in the same position. If
the cross hairs are not in the same position, the
telescope alignment screws must be adjusted as
follows:
A. Adjust the telescope alignment screws until the
cross hairs are midway between the original
position (center of receiver window) and the
current position (after the scope was rotated
180°). See Figure 19.
B. Return the scope to its original position (rotate
180°) and repeat steps 8 through 10 until correct
alignment is achieved.
NOTE
No further adjustments are required when the
cross hairs are centered on the receiver window
with the scope in both 180° positions.
11. Repeat the alignment procedure for the receiver
module (steps 6 to 10).
12. Remove the Telescopic Alignment Tool and re-install
the sun shades.
13. Bypass all external gas alarm devices that are
connected to the receiver outputs, and then apply
24 Vdc power to the modules.
14. Upon completion of warm-up mode (approximately 2
minutes or less), the receiver may display either a
green LED (normal mode) or a red LED (alarm
mode). An alarm condition is not abnormal and will
be cleared by performing a zero calibration.
15. Perform a zero calibration. (Refer to “Zero
Calibration” in the Calibration section of this
manual.) Any faults or alarms that may be present
as a result of the alignment process will be cleared.
16. When Basic Alignment and Zero Calibration have
been successfully completed, a green LED should
be displayed on the Rx module and the analog
signal output level should be 4.0 milliamperes.
17. Confirm proper operation by blocking the light beam
with a solid object such as cardboard until a beam
block fault is generated.
18. Confirm proper operation by installing the optical
test film (p/n 007902-001) into the light beam and
inspecting for corresponding signal output level of
1.2-1.8 LFL-meters on the HART Field
Communicator Process Menu screen (or 7.8 - 9.8
mA output). If an alarm condition is generated, it
should clear when the film is removed from the
beam.
19. Tighten all mounting bolts to 20 lb.-ft. minimum with
care not to disturb the alignment. The telescope is
useful during this process to give a visual indication
to judge the affects of the tightening process on the
alignment.
POSITION A = ORIGINAL ALIGNMENT
POSITION B = CROSS HAIR POSITION AFTER ROTATING SCOPE 180°
POSITION C = MIDWAY BETWEEN POSITION A AND B
STEP 1: CENTER CROSS HAIRS ON TARGET USING
ADJUSTMENT BOLTS ON MOUNTING PLATE
(POSITION A).
STEP 2: ROTATE SCOPE 180°. ALIGNMENT
ERROR CAUSES CROSS HAIRS TO
MOVE TO POSITION B.
STEP 3: ADJUST ALIGNMENT SCREWS ON SCOPE
TO PLACE CROSS HAIRS AT POSITION C.
STEP 4: ROTATE SCOPE 180° TO ORIGINAL POSITION.
STEP 5: REPEAT STEPS 1 TO 4 UNTIL THE UNIT IS
CORRECTLY ALIGNED.
A2314
Figure 19—OPECL Alignment using the Telescope Alignment Tool