Oden Control P220L, User Manual

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6 THE CALIBRATION SYSTEM
To calibrate the actuator/valve-system means to identify the closed valve position which corresponds to the closed
position of the control signal, normally 4 mA. There are two types of calibration methods; Power Calibration
(mostly used) and Position Calibration. Which one to use depends on type of application.
6.1. Power Calibration
The Power Calibration is the most common method to make sure the actuator finds the closed position. The
calibration can be performed manually or automatically.
Manual Power Calibration using OVP software
To manually perform the calibration press the Power Calibration-button in the main menu. When ready, the
actuator will move to the control signal position.
Manual Power Calibration without using OVP software
To manually perform a Power Calibration without using the OVP software:
1. Disconnect the power, 24 V DC.
2. Short-circuit the pins TD and RD at the RS 232-connector.
3. Connect the power, 24 VDC. The actuator will perform a calibration. When ready, the actuator will
move to the control signal position.
4. Remove the short-circuit of TD and RD.
Automatic Power Calibration
By enable the Automatic Calibration-function in OVP, an automatic Power Calibration will be performed every
time the valve reaches its closed position. If the valve remains in closed position, this sequence will be repeated
every 20 minutes. This function can be adjusted and disabled in OVP software. The main reason for this routine is
to reduce the risk of valve jamming.
The actuator position is automatically saved to a permanent memory during a power failure. If the valve position
has been changed during lack of power, the motion will be detected. This detection occurs during maximum 8
hours after a power failure.
When the power returns, an automatic calibration will be performed. After the calibration the actuator will respond
to a control signal if present. The maximum opening angle, starting from this closed position, is either set by
default or by the customer in the OVP software.
Please not that the maximum range for the automatic permanent saving of the position value at a power break is
12,000 degrees (33 turns) for turning actuators and 330 mm (with a screw pitch of 10 mm) for linear actuators. If
any of these ranges have been extended no saving occurs. It is possible to maintain the calibration point by
continuously power the actuator for example by an UPS (Uninterrupted Power Supply).
6.2. Position Calibration
The Position Calibration method is recommended if the valve has no mechanical stop or is too sensitive to stand
the torque/force of the Power Calibration. When performing a Position Calibration you are manually setting the
calibration position and the maximum opened position.
To perform a Position Calibration:
1. Disconnect the power, 24 V DC
2. Check that there is no computer connection to the RS232 connector.
3. Move the valve manually to closed position.