STC Smartscan NG2, Руководство пользователя

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EUD-2018086-00 Rev.3, SmartScanNG² User's Guide for Wayside Enclosure Components, 14 May 2021
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IMPORTANT: To ensure an accurate activation point, always place the shunt BEFORE
pressing the Calibration Switch.
If the PD8-Plus cannot achieve calibration, it will blink the relay drive LED three (3) times in
rapid succession, indicating a calibration error. The unit will continuously repeat the calibration
procedure (there is no need to press the Calibration Switch), allowing you to troubleshoot the
track circuit, wiring, and battery. Once the issue has been corrected, repeat the calibration
procedure.
Both the ZEPIC III and Zepic PD8-Plus have a two-wire track circuit and will activate an equal
distance on both sides of the track feed point.
PD8-Plus Short-Track Circuit Calibration
1. The system may fail the 10 ft calibration verification step noted above if the installation
is using 26KHz and the desired CAL point is ~30ft from the feed points (Short track
circuit), and the bungalow is near the track (short track wires).
2. If this is the case, reconfigure the PD8-Plus to a lower frequency that is compatible with
other equipment that may be on the track. In general, changing from 26KHz to 20KHz
or 17.5KHz should solve the short-track circuit calibration issue.
3. Once the module has been reconfigured for the new operating frequency, repeat the
normal calibration procedure detailed above.
PD8-Plus Troubleshooting and Application Notes
1. If the unit will not calibrate, watch the relay drive LED for approx 45 seconds. If it
blinks, this means the PD8-Plus has turned its receiver gain to the maximum setting
and cannot see the track shunt. Look for open circuits between the PD8-Plus and the
shunt on the track. I.e., track wires, bond wires, etc.
2. The PD8-Plus will look equally in both directions. If one side of the circuit has insulated
joints, the PD8-Plus will operate. However, the activation distance will not be the same.
In general, track circuit equipment cannot see past insulated joints.
3. Audio overlay systems like the PD8-Plus will not work with wideband shunts in their
track circuit range.
4. If the relay drive is stuck ON, look for short circuits between the PD8-Plus and the
desired pick point.
5. The greater the distance between the PD8-Plus and track connections, the greater the
effects ballast will have on the PD8-Plus performance.
6. Presence output is a dry contact configuration Form –C dry contact, 225mA max
current. (N.O. contact with no train presence)
7. In good track ballast conditions, a PD8-Plus circuit can travel up to 500 ft in each
direction. Rotating operating frequencies to avoid interference with other equipment is
recommended.
8. The higher the operating frequency, the shorter the track circuit.