Omega Vehicle Security OMP-MODL manual 11-124

11... APPENDIX F: FILTERING OPTIONS

The above plot demonstrates the performance of the 50Hz software filtering. The plot is from actual data collected by a OMP-MODL (which utilizes the same digital signal processing) during the development and testing of the software filtering feature. A 5Vp-p AC swept frequency was super-imposed on a 2.5VDC and input into a OMP-MODL equpped with an HLIM-1 The input channel was configured with the 50 Hz filtering enabled. As can be seen from the plot, at 50 Hz, the amplitude of the noise is radically reduced.

As with all filtering, a compromise is involved. Line Rejection filtering adds approximately 8.5 mS for 60 Hz rejection (10mS for 50Hz) to the measurement and processing time required for a reading.

If the desired sampling rate allows, enable Line Reject filtering by selecting 50 or 60 Hz depending on the power line frequency used in the installation locale. In the USA, 60 Hz should be selected.

11-124 USING THE OMP-MODL