Delta RMC101 - Manual (Page 835)

Appendix C: Parameter Field Reference
C-65
1. Transducer Compensation: The Scale parameter compensates for differences in analog
transducers. Each transducer will indicate a different current or voltage level for the same
pressure. Usually, only a small change from the default value is necessary to compensate the
transducer.
2. Pressure Translation: A second and more useful feature of Scale is its ability to translate a fixed
physical reading to usable pressure units (pressure units from thousandths to hundredths or vice
versa).
Click here for Pressure/Force Scale and Offset examples
C.5.5 Offset A, Offset B (Pressure)
Default: 0
Range: -32768 to 32767
TIP: On the Tools menu, click Scale/Offset Calibration to help calculate Scales and Offsets.
The Offset fields have different uses depending on whether the axis will be used for differential
force or single-ended pressure.
For single-ended pressure, Offset A is used with Scale A to convert Counts A to Actual Pressure;
it shifts the Actual Pressure with respect to the analog input zero. Offset B is unused.
For differential force, Offset A is used with Scale A to convert Counts A to Actual Force A while
Offset B is used with Scale B to convert Counts B to Actual Force B. Both offset the force units by
their amount.
These offsets can be defined in either of the following ways:
In the above equation, P0 and P1 are two pressure or force values in the desired pressure or
force units, and C0 and C1 are the corresponding counts given in the Counts A or B field.
Click here for Pressure/Force Scale and Offset examples
Why Bother?
These offsets can be used to set your 0 point at any pressure reading. They are often left at 0 for
voltage feedback gauges (e.g. 0 to 10V or 0 to 5V), but will likely need to be non-zero for current
(4 to 20mA) gauges. This is because zero pressure or force units will have zero counts on a
voltage gauge, but will have 6500 counts (4mA) on a current gauge.