Delta RMC101 - Manual (Page 866)

RMC100 and RMCWin User Manual
D-4
your Scale and Offset settings. For pressure axes, this field is renamed COUNTS A. For force
axes, there are two counts fields, COUNTS A and COUNTS B, corresponding to the first and
second input channels. Refer to the appropriate section below for the type of feedback
transducer(s) you are using:
Magnetostrictive Displacement Transducers (MDT)
The counts represent the number of 120MHz time periods that have passed either between the Start
and Stop return pulses for a Start/Stop MDT or from the rising to falling edges of a PWM MDT.
Counts will read 0 when the MDT does not return counts. The actual distance from the end of the rod
to the magnet is found by multiplying the counts by the gradient value of the MDT. Therefore, to
translate from counts to distance, use the following formulas:
Gradient in msec/in:
Example: An MDT has a gradient of 9.153 msec/in. The counts read 6000. The following equation
finds the position:
Gradient in m/sec:
Example: An MDT has a gradient of 2845.06 m/sec. The counts read 6000. The following
equation finds the position:
Synchronous Serial Interface (SSI)
The counts are equal to the counts returned from the SSI interface. That is, SSI transducers return a
digital count value. The resolution of the counts is defined for the particular SSI device. Therefore, to
translate from counts to distance, use the following formula:
For linear devices, the resolution will be a unit of linear measure, such as 5um. For rotational devices,
the resolution will be in degrees or fractions of a revolution.
Example 1: An SSI has a resolution of 5 um per count. The counts read 6000. The following equation
finds the position: