VVP10 HART
HART
®
VALVE POSITIONER
INSTALLATION, OPERATION, CONFIGURATION AND MAINTENANCE MANUAL
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Figure 3.17 – Assembly for position return current trim.
Figure 3.18 – Assembly for loop current trim.
PRESSURE
Pressure calibration is available for Input, Output 1 and Output 2 pressure sensors. Individually, user must apply the
lower and upper pressure references for each of the sensors. The following procedure exemplifies these calibrations
found under
Trim/Pressure
directory.
First, user must remove all the supply pressure (which will also cause zero pressure at the outputs) and perform the
lower pressure calibration on the three sensors, informing the value (in this case, zero).
Subsequently, he must apply the working feed pressure (eg. 30 psi) and calibrate the input sensor with this value.
With the position at 0%, all air from air supply will be sent to output 2. User will then be able to calibrate this sensor
with the same input value. By changing the control position to 100%, all of the air from the air supply is being sent to
output 1. User can then calibrate this sensor to the same input value.
This process can be repeated as many times as the user finds necessary, until the sensor pressures are perfectly
calibrated at the lower and upper points.
TEMPERATURE
The temperature calibration is the simplest one offered by the positioner, where user only sends the value of the
ambient temperature measured by some external thermometer. The equipment automatically adjusts the internal
temperature measurement based on the value sent by the user.
This process can be repeated as many times as the user deems necessary, until the temperature is perfectly calibrated.
Temperature calibration can be found under
Trim/Temperature
directory.
WARNING
Pressure calibration will be available only for positioner models with installed pressure sensors. Verify the
Ordering Code for this characteristc (section 6.2).
