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IO/Inputs/[DIN]/Count/SampleTime Registry Key NAME IO/Inputs/[DIN]/Count/SampleTime DEFAULT 0.0 (seconds) DESCRIPTION This defines a sampling period in seconds. A fractional value may be specified. Normally Counts accumulate until reset separately by the user threw the WebUI, JRMON or other application. This is the case when SampleTime is set to 0.0 (default). When a nonzero time is defined the counter displays the total count accumulated during that period. For instance, with the appropriate combination of Multiplier and SampleTime  the counter can display Revolutions Per Minute (RPM) for a input using a Hall Effect sensor mounted on a wheel hub. NOTES When RPM is measured in this fashion it is perhaps better to allow an application to perform the calculation. With access to the I/O log and the appropriate Java class the application can average pulses over a moving window or sample time for the accurate real-time measurement of high RPMs. When the wheel is rotating extremely slowly the application can then use the pulse-to-pulse timing to derive an estimate of fractional RPMs and even the rate of change. This would be a useful approach for use with a wind turbine as an example. SEE ALSO HELP Topics: JRMON, COUNTING, DIN [/flash/manpages/registry.hlp:3074]