Delta RMC151 - Manual (Page 1008)

RMC70/150 and RMCTools User Manual
Type: Axis Parameter Register
RMC70 Address: %MDn.38, where n = 12 + the axis number
RMC150 Address: %MDn.38, where n = 24 + the axis number
System Tag: _Axis[n].OutputScale, where n is the axis number
How to Find: Axes Parameters Pane, All tab: Output
Data Type: REAL
Units: V/100%
Range: non-zero
Default Value: 10
Description
The Output Scale scales the Control Output to the actual Control Output voltage. This
scale is defined as volts per 100% of Control Output. For most systems, this value should
be left at its default of 10.
There are three main reasons for setting this parameter to a value other than 10:
1. Output Range Less Than ±10V
For systems that require a Control Output range of less than ± 10 V, Output Scale
should be set to the maximum required Control Output voltage. The Output Limit
parameter should also be set to the same value.
For example:
For a system requiring a Control Output range of only ±5V, set this parameter to 5.
The Output Limit parameter should also be set to 5V so that the Control Output will
never exceed ±5V. Thus, you can work with the full scale output range and won't have
to worry about the Control Output exceeding ±5V.
2. Convert ±10V to 4-20 mA
The Output Scale and Output Bias parameters can be used on conjunction with the
VC2124 voltage-to-current converter to convert the Control Output from ±10V to 4-20
mA. Delta does not recommend using valves or drives that require a 4-20mA input.
Delta recommends using a valve or drive that requires a ±10V input voltage or, for
servo valves, a current centered around 0, such as ±90mA. However, for the cases
where 4-20mA cannot be avoided, the Using the VC2124 topic explains how to set up
the RMC parameters to work together with the VC2124 to produce a 4-20mA output.
3. Compensate for Oil Temperature Changes
The system gain may change with temperature for hydraulic system, requiring
different values of gains and feed forwards. Changing the Output Scale parameter will
in effect scale the gains. The Output Scale parameter provides a simple method to
scale the gains and feed forwards to compensate for oil temperature changes.
9.2.2.6.9. Fault Input Polarity
988 Delta Computer Systems, Inc.