Micromod MOD: 1750N Output holder for MOD 30ML - Manual (Page 26)

Output Holder Instructions
CONFIGURATION
3. The compound uses a VCIM (RETURN) and a VCI conditioning (RETURNF1) blocks for
reading the feedback from the output holder. This is the feedback of the output value
from the output holder sent to the field. This value is tied to the output track input (OPTI)
of the PID block so that the PID block tracks this value upon start up. This is how a bump
less transfer of output value is achieved. If you do not need bumpless transfer of output,
you can optionally remove these two blocks.
4. The AOM block is configured as shown below for Restart/Failsafe conditions:
Figure 4 .11. PID_OH1 Compound
The Restart output is configured as Preset with a value of –25. The reason for this is
when a faulty controller is replaced with a new or a repaired one, a momentary zero
output from the controller at startup will be seen as a valid input by the output holder and
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