STC Smartscan NG2, Manual

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May 2021, SmartScanNG² User's Guide for Wayside Enclosure Components, EUD-2018086-00 Rev.3
10.7 Calibrating the PD8-Plus Presence Detector
1. Obtain track & time authority.
2. From the center of the gating transducers, measure the distance you want the track
circuit to pick up the presence of a train.
3. The recommended distance is at least 50’ (15.24 m) and
no more than 150’ (45.7 m).
4.
At the point just measured, place a 0.06Ω shunt across
both rails. The track must be shunted before the
calibration switch is pressed.
5. Press and HOLD the Calibration Switch until the relay
drive LED starts blinking. Release the switch and the
LED will stop blinking. The ZEPIC III will automatically
begin the calibration process. NOTE: The track shunt
MUST remain in place during the calibration process.
1 20 1 20
1
10
SOTC CALIBRATION
SWITCH
SmartScanNG² CHASSIS
6. The relay drive will pick up (LED on) when the unit has successfully calibrated. This
process can take up to 45 seconds to complete.
Verification
1. After calibration, lift the shunt, and the relay drive should drop (LED off). Replace the
shunt, and the relay drive will pick up (LED on).
2. Move the shunt approximately 10’ farther out from the calibration point. The relay drive
should not pick up (LED stays off). If this test fails, perform Short Track Calibration
(detailed below).
3. The PD8-Plus is now operating properly and will activate at an equal distance on either
side of the track feed point.
4. After trackside calibration procedures have been successfully completed, place a
temporary shunt across the track wires inside the bungalow and verify that the signal
system goes to stop. Once verified, remove the temporary shunt.
NOTE: For older model
SmartScanNG Chassis
you must remove
Controller Module to
access Calibration Switch
on Zepic III board.
NOTE: the relay drive LED is
the same as the SOTC LED
visible on the lower right side of
the NG² Chassis cover.
PD8-Plus