Substitute Value Strategy; Approach Substitute Value; Leave Substitute Value Strategy After An Error - WAGO 750-632 Manual

WAGO-I/O-SYSTEM 750
750-632 Proportional Valve Module
5.3.7

Substitute Value Strategy

The substitute value is output if the internal data bus has an error and the
replacement strategy is correspondingly parameterized.
The substitute value strategy can be configured, so that either a substitute value is
output or the last valid value from the process image is retained.
The behavior can be configured as follows:
• Section "Tables 50, 51 (Process Data Handling, Valve 1, Valve 2)"
• Section "Configuration and Parameterization with WAGO-I/O-CHECK
5.3.7.1

Approach Substitute Value

The substitute value can be approached in two ways:
• Approach substitute value "hard": There is no ramp, rather the
parameterized substitute value is output directly.
• Approach substitute value "soft": The stop ramp is used to approach the
substitute value.
The behavior can be configured as follows:
• Section "Table 40 (Additional Module Parameters)"
• Section "Configuration and Parameterization with WAGO-I/O-CHECK"
5.3.7.2

Leave Substitute Value Strategy after an Error

Once the I/O module fault is remedied, the substitute value strategy is exited via a
positive edge for the SPL_EN bit. The channel is now in "Automatic mode".
Avoid unintended jumps in the actual value!
Forsaking the substitute value strategy may lead to unintended jumps in the actual
value. This is due to a difference between the then actual setpoint value and the
substitute value. To avoid the problem, please proceed as follows:
1. Evaluate the error situation, e.g., using the respective diagnostic
information from the fieldbus coupler/controller.
2. Read the actual value.
3. Set the actual value read as the setpoint value.
4. Output the positive edge of the SPL_EN bit.
Manual
Version 1.3.0, valid from FW/HW-Version 01/01
Function Description 49