13
thus the results are likely to differ when compared with other measurement methods such as
measurement trains.
Top faults of less than 2 mm in depth are not displayed to the user. Top faults have to exceed 5 mm
in order for the software to treat them as cycles (count them and report them). The reported cycles,
depending on their position along the track, may or may not form a cyclic top fault. The software
does not tell the user whether or not the cycles form a cyclic top fault, but the stars displayed on the
graph can be used as a guide to see if there are three or more cycles in a regular interval.
The software will show any cycles present on the track, even if just one is present (which is not
enough to form a cyclic top fault). Results are likely to differ when compared to other means of
measurement such as the measurement train which reports the cycles only if they form a cyclic top
fault and exceed other types of thresholds.
6.2
Gauge
Note: This measurement is taken from the internal running edges of the tracks at P-point (usually -
14mm) distance from the top of the rail.
Range
-25/+65mm (on nominal)
Accuracy
±1mm
Resolution
0.1mm
6.3
Super-Elevation
Range
±250mm
Accuracy
±1mm
Resolution
0.1mm
Super Elevation (SE) is measured across the running rails and is displayed as height differential
between the high and low rail in millimetres
The default sign convention is: Left rail up is positive Cant/SE
During Cyclic Top measurements the software records the trolley half labelled “L” as being
the left rail. During geometry measurements the left and right side is determined by the
direction of travel.
6.4
Twist
Range
±250mm
Accuracy
±1mm
Resolution
0.1mm
