Delta RMC101 - Manual (Page 654)

RMC100 and RMCWin User Manual
A-2
described below.
Use the following tips when tuning I-PD motion:
• The Proportional Gain works the same as in the PID.
• The ratio of the Integral Gain to Proportional Gain determines the response. For a faster
response (to get into position quicker), increase the Integral Gain/Proportional Gain ratio.
• The Differential Gain works the same as in the PID.
• Feed Forwards and Accel Feed Forwards are ignored.
Why Bother?
• The I-PD is simpler than the PID for basic moves where the goal is simply to get to position.
• Some gearing applications may benefit from the I-PD, as explained above.
A.1.2 Set Count Offset Command
Character: #
Decimal: 35
Hexadecimal: 0x23
Command Value: Count Offset
Note: This command is supported in RMC100 CPU firmware dated 20030403 or later.
This command is used to offset the Transducer Counts on SSI and Analog Velocity axes, as
explained below. This Count Offset value can be saved to Flash with the Update Flash (U)
command and will then be valid on the axis until changed by another Set Count Offset (35)
command.
SSI Axes:
This command offsets the Transducer Counts (before it is converted to position units) by the
amount specified in the Command Value ( 32767 to +32768). This is useful on SSI rotary
absolute axes for setting the zero point of the axis.
Analog Velocity Axes (control and reference):
This command offsets the Transducer Counts (before it is converted to velocity units) by the
amount specified in the Command Value ( 32767 to +32768). This is useful for setting the zero
velocity point of an axis with tachometer feedback.
Example:
A tachometer is wired to an RMC100 analog input. The Transducer Counts field (the Counts field
in the Status area of RMCWin) shows -150 when the tachometer is not rotating. This incorrect
feedback will cause the axis to rotate after issuing a command for 0 velocity.
Issuing a Set Count Offset (#) command with a command value of 150 results in the Counts field