Instruction Manual
D103785X012
Calibration
June 2017
43
Figure 4‐1. Crossover Point
ACTUATOR
STEM
FEEDBACK
ARM
90
_
A6536-3
7. Place the instrument In Service and verify that the travel properly tracks the current source.
If the unit does not calibrate, refer to table 4‐1 for error messages and possible remedies.
Table 4‐1. Auto Calibrate Travel Error Messages
Error Message
Possible Problem and Remedy
Power failure occurred during Auto Calib
The analog input signal to the instrument must be greater than 3.8 mA. Adjust the current output
from the control system or the current source to provide at least 4.0 mA.
Auto Calib did not complete within the time limit.
The problem may be one or the other of the following:
1. The tuning set selected is too low and the valve does not reach an end point in the allotted time.
Select
Manual Setup
>
Tuning
>
Travel Tuning
>
Stabilize/Optimize
then
Increase Response
(selects next
higher tuning set).
2. The tuning set selected is too high, valve operation is unstable and does not stay at an end point
for the allotted time. Select
Manual Setup
>
Tuning
>
Travel Tuning
>
Stabilize/Optimize
then
Decrease
Response
(selects next lower tuning set).
Insufficient travel
Prior to receiving this message, did the instrument output go from zero to full supply? If not, verify
instrument supply pressure by referring to the specifications in the appropriate actuator instruction
manual. If supply pressure is correct, check instrument pneumatic components (I/P converter and
relay).
If the instrument output did go from zero to full supply prior to receiving this message, then verify
proper mounting by referring to the appropriate mounting procedure in the Installation section.
Verify travel sensor adjustment by performing the appropriate Travel Sensor Adjust procedure in the
Calibration section. Making the crossover adjustment with the valve positioned at either end of its
travel will also cause this message to appear.
Drive signal exceed low limit; check supply
pressure
1. Check supply pressure (reverse‐acting relay)
2. Friction is too high.
Drive signal exceed high limit; check supply
pressure
1. Check supply pressure (direct‐acting relay)
2. Friction is too high
