Nivus OCM F, Инструкция по эксплуатации

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Installation and Connection
OCM F - rev. 05 / 06.04.2018 page 35
14.8.4 Control Algorithm
If the regulator function is selected (see also chapter “23.7 Parameter Menu “Control Unit””),
relay 4 is used for “CLOSE SLIDE VALVE” and relay 5 for “OPEN SLIDE VALVE” function.
This assignment cannot be modified.
The digital inputs are free programmable for position feedback. To ensure correct and failsafe
slide valve drive necessarily use the messages “SWITCH OPEN”, “SWITCH CLOSED” and
“TORQUE CLOSED” of the slide valve drive.
The input current per digital input is 10 mA.
Slide valves driving messages
In case of driving the slide valves via the digital inputs always use all the three messages.
Activating one message only may result in disturbed regulator operation.
The regulator can be operated with external or internal set point.
External setpoints have to be routed to analog input 4 (clamps 41+ and 42 GND).
In case of using a 4…20 mA signal as external setpoint, this signal can be monitored for ca-
ble breaks and short circuits. If errors should occur the OCM F is going to access the internal
setpoint (
→
in case of using external 4…20 mA setpoints and error monitoring always set the
internal setpoint additionally!).
The following equation applies for the internal calculation of the slide valve control time:
Control time = (setpoint – flow
actual value
) • P_factor •
max. slide valve runtime
max. flow