The features and specifications of equipment given on the below are illustrative only. They are not a guarantee of performance in a particular case. For more information, please contact us.

Feature	CAT	RCA	HSRCA
Weight & portability	Portable, 7kg instrument, 11kg when in case. Operated by one person	Not portable: train mounted	Not portable: train mounted
Measuring speed	Walking speed: 2-5km/h	Up to 20km/h demonstrated	Typically 60-100km/h; lower speed possible with reduced accuracy, particularly at long wavelengths
Measuring principle	Contacting transducer	Contacting transducer	Axlebox accelerometers
Measurement of	Single rail	Both rails simultaneously	Both rails simultaneously
Requirements regarding train or vehicle	None: portable system	Minimal wheel irregularities	Minimal wheel irregularities Electronic tachometer Good primary suspension: minimal friction elements
Typical accuracy in 30-100mm wavelength range	Better than 0.001mm RMS	Better than 0.010mm RMS	Better than 0.015mm RMS
Computing requirements	Laptop, 75MHz Pentium or better	Laptop or desktop, 75MHz Pentium or better	Desktop, 500MHz or better
Software	Proprietary, Windows based	Proprietary, Windows based	Proprietary, Windows based
Data collection, signal processing & display [1]	- Profile of one rail at 1mm or 2mm interval and 0.01 micron resolution - Filtered profiles [2] - RMS amplitudes in “block” or moving window [2] - Peak-to-peak amplitudes in block or moving window [2] - Percentage exceedence [4] - One-third octave band spectra	- Profile of both rails at 2mm interval and 1 micron resolution - Filtered profiles [2] - RMS amplitudes in “block” or moving window [2] - Peak-to-peak amplitudes in block or moving window [2] - Percentage exceedence [4]	- RMS amplitudes in “block” [3] - Percentage exceedence [4,5]
Automatic detection discrete irregularities (e.g. welds)	No	No	Yes, ranked into up to 7 ranges of severity
Annotation of records with features of line (bridges, etc.)	No	Yes	Yes
Annotation of records with features of line (bridges, etc.)	- Corrugation surveys and troubleshooting - Quality Assurance for grinding - Accurate measurement of short lengths of track (2- 5km/h) - Measurements for acoustics work - Verification and calibration of other equipment, e.g. RCA and HSRCA	- Corrugation surveys for metros or other relatively small railway systems - Quality assurance for grinding - Accurate measurement of moderate lengths of track	- Measurement of complete rail systems to assess grinding requirements

Notes:

1. All software can export ASCII files of calculated data e.g. for post-processing with other software.
2. For wavelength ranges 10-30mm, 30-100mm, 100-300mm, 300-1000mm, 1000-3000mm, 30- 300mm, 300-3000mm and 150-1500mm.
3. For up to 7 non-overlapping, user-specified wavelength ranges
4. The “percentage exceedence” is the percentage of the measured length over which a measurement of the profile exceeds a specified limit. The measurement can in principle be of any quantity e.g. raw or filtered profile, RMS or peak-to-peak average displacement in a moving window.
5. For the HSRCA, percentage exceedences can be calculated for up to seven specified amplitude limits.