80-4280-10, Rev. 4
29
0% and 100% POSITION
CALIBRATION PROCEDURE
PUSHBUTTONS
method
1. Position the actuator to the desired 0%
position.
2. Press and hold the “CALIBRATE” and “POS
0%” pushbuttons on the DCM’s local interface
panel until the “ACKNOWLEDGE” LED lights.
3. Position the actuator to the desired 100%
position.
4. Press and hold the “CALIBRATE” and “POS
100%” pushbuttons on the DCM’s local
interface panel until the “ACKNOWLEDGE”
LED lights.
5. Adjust over-travel limit switches as necessary
to accommodate the new rotation (page 24).
HART
method
HART DD Menu Location: MENU 5B
Functions> Configuration> Position Sensor Setup
Command: Set Pos 0%
Position the actuator to the desired 0% position
and run the “Set Pos 0%” function.
HART DD Menu Location: MENU 5B
Functions> Configuration> Position Sensor Setup
Command: Set Pos 100%
Position the actuator to the desired 100% position
and run the “Set Pos 100%” function.
CHANGING TRAVEL IN
DEGREES PROCEDURE
HART
method
HART DD Menu Location: MENU 5A
Functions> Configuration> General Setup
Command: Travel
Enter the full stroke rotation in degrees and press
the ENTER key. Remember to press the SEND
key to execute the change.
SERIAL
command method
Command: travel
Arguments:
###
: Enter the full stroke rotation in
degrees. (e.g.: “travel 90” for 90 degree rotation)
Note for HART & Serial:
The 0% position will
remain the same and the 100% position will
change to accommodate your calibration.
It is important to note, however, that when the
actuator full travel is short-stroked to something
less than 100°, the 2-wire Position feedback span
is reduced proportionately. For example, the 2-wire
Position signal is normally calibrated to provide
a 4–20 mA signal (16 mA span) proportional to
0–100% travel of 100°. If the travel is short-stroked
to a value less than 100° full travel, such as 60°,
then the feedback signal representing the new,
shorter full travel is reduced proportionally. In this
case, the span would be 60% of 16 mA, or 9.6 mA.
Assuming the zero position point was not changed,
the resulting 2-wire position signal is 4–13.6 mA
representing 0–100% travel. Depending on the
short-stroke procedure utilized, the zero position
point could be changed, if desired.
Note that the standard 4-wire actuator-powered
position signal is also available at terminals 17 (+)
and 16 (–). Because this signal is sourced by the
DCM, it maintains the full 16 mA span of the 4–20
mA signal to represent full travel, regardless of how
much the travel is short-stroked.
