STC SmartScanIS, User Manual

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EUD-2016026-00 Rev.2, SmartScanIS User’s Guide for Union Pacific, 14 January 2021
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A.16 No Basetime Reader 2 Alarm
There isn't a No Basetime Reader 2 alarm when a 2200-750 Reader is attached to the system.
This alarm only appeared under an earlier version of the system, one that used a 2200-504TB
Reader.
A.17 Reverse Direction Detected Alarm
Trains that are being scanned correctly will have axles whose on times (that is, the time during
which an axle passed between the gating transducers) are less than their off times (that is, the
time during which no axle passed between the gating transducers). For each axle of a passing
train (except for the first axle), the system checks for an on time that is greater than the off
time. If the axle's on time is greater than its off time, the system reverses the opening and
closing gate assignment for TO1 and TO2. If this occurs on the second or third axle of the
train, the system reverses the direction locked-in by the first gating pulse.
The Reverse Direction Detected alarm indicates that the system entered a state where it is
scanning for bearing temperatures when the axles are outside the scanning gate. In this state,
the transducer that should be opening the scanning gate is considered by the system to be the
transducer that is closing the gate. Likewise, the transducer that should be closing the
scanning gate is considered the transducer that is opening the gate.
A.18 Short Train Alarm
The Short Train alarm indicates that a train had fewer than 50 axles.
A.19 Sliding Wheel Alarm
The Sliding Wheel alarm indicates that a combination of very low bearing and wheel
temperatures were found on a given axle in conjunction with high wheel temperatures
recorded on the remaining axles of a car. This condition could mean that the wheels on the
affected axle were sliding, rather than rolling, on the rail.
The Sliding Wheel alarm is both an Exception Alarm and a System Alarm.