Omega Vehicle Security OMP-MODL manual Appendix F Filtering Options, ADC Input Filtering, 11-123

11.. . APPENDIX F: FILTERING OPTIONS

APPENDIX F: FILTERING OPTIONS

Many of the Interface Modules can be configured with filtering options for reducing the noise picked up on sensor or input signal wiring. A short discussion of two of the filtering methods that are available to the User through icon configuration dialog boxes follow:

ADC Input Filtering

In the OMP-MODL, a first order noise filter can be enabled within many of the analog input icon configuration dialog boxes. First order filtering reduces High frequency noise that may be picked up by sensor wiring. However, filtering slows down the rate at which a channel can be sampled as it adds additional settling time to the total time required for a reading.

Additional settling time required for each of the three levels is specified in the table below.

If speed of execution of the Program Net is not of concern, utilize the High level of filtering for best noise rejection.

Filter Level	Additional Settling Time
None	0
High	15 mS

50Hz / 60Hz Sofware Filtering

Noise radiated from utility power lines (including house and building wiring, appliances and extension cords) and picked up by sensors and associated wiring is one of the most common sources of data acquisition error.

The OMP-MODL has additional software based filtering capability designed to remove 50 Hz or 60Hz power line sourced noise from incoming signals. This filtering capability is especially helpful in applications with sensors and/or wiring which is in close proximity to utility wiring.

USING THE OMP-MODL 11-123