Rockwell Automation 1771-QB Linear Pos. - Manual (Page 126)

Initializing and Tuning the Axes
Chapter 8
8Ć8
Table 8.B
Transducer Calibration
Number of Transducer Calibration Constant
Circulations Microsec/Inch Microsec/mm
1 9.0500 0.35600
2 18.1000 0.71200
3 27.1500 1.06800
4 36.2000 1.42400
5 45.2500 1.78000
6 54.3000 2.13600
7 63.3500 2.49200
8 72.4000 2.84800
2. Enter the transducer calibration constant from the table into the parameter
block for the axis. Send the new parameter block to the module.
3. With the hydraulic pump off, mark the position of the axis relative to a
stationary structure. You will need to measure the change in the axis
position to within 0.001 inches.
4. Record the initial axis position value from the module. This value is in the
status block words 12 and 13 at N44:12 and N44:13 for axis 1.
5. Turn the hydraulic pump on and move the axis approximately six inches,
using one of the following three techniques:
if you have previously tuned your axis use the command block (at
N45:131) to either jog the axis or perform a setpoint 13 move
if you have not previously tuned your axis, with axis power off,
disconnect the servo valve from the module and use the servo valve
nulling screw to move the axis
if you cannot easily access the valve null screw, with axis power off,
disconnect the transducer gate leads from the wiring arm. Restore
power and then jog the axis at one inch per second using the jog bits.
(This is called the open-loop jog.) With axis power off, reconnect the
trandsucer gate leads. restore power and continue.
6. Turn the hydraulic pump off.
7. Using your caliper, measure the distance travelled by the workpiece, and
record this value as the actual distance.