Other Control Functions
2/03 10260A Series Actuators – Installation, Operations, and Maintenance 51
6.2.3 Split Valve Configuration
A common heat or cool type process requires two valves. In this case the controller has only one output.
The two motor positioners are calibrated differently, one responds to 4 mA to 12 mA and the other
responds to 12 mA to 20 mA. At 12 mA both valves are closed, one opening below 12 mA and the other
above 12 mA. It is also easy to have deadband in the center where both valves are closed, or overlap where
both are open. Deadband is obtained with the zero and span adjustments on the motor positioner PCA.
Figure 6-5 Interconnection Diagram
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