Appendix E: Discrete Input (Di) Block - Emerson DXP-FF Installation, Operation & Maintenance Manual

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Appendix E: Discrete Input (DI) Block

Discrete INPUT Blocks (DI Block)
There are 5 Discrete Input Blocks available on the
SCM-FF. The DI block takes the manufacturer's discrete
input data, selected by channel number, and makes it
available to other function blocks at its output. These DI
blocks become available to the user when linked to one
of the Transducer Channels available for inputs.
A host may retrieve internal information at any time and
alarms are reported as they occur. To make a light come
on or another valve close requires a DI to publish the
information on the bus.
Channels
The 5 DI Function Blocks in the device are associated to
the real world by setting the CHANNEL parameter to the
desired Transducer Channel. Illustration 11 shows the
relationship between Transducer channels and the DI
assigned channels. The output of the DI block (viewed in
the OUT_D parameter) is defined by the DI block's
CHANNEL assignment. The valid settings for the CHAN-
NEL parameters are listed in Table 7.
By resetting a DI CHANNEL parameter to a different
transducer channel number (0, 6-13, see Table 1) an
end user may customize the functionality of the SCM-FF
to fit a particular application requiring DI's on temperature
limits and cycle counts instead of the defaults.
Illustration 11.
Channel Assignment for DI Function Blocks
Transducer Transducer Transducer
Channels Channels Channels
Valve is Opened/ Valve is Closed Valve is Opened/ Valve is Closed Valve is Opened/ Valve is Closed
Valve is Opened Valve is Opened Valve is Opened
Valve is Closed Valve is Closed Valve is Closed
Auxillary Limit Switch.input Auxillary Limit Switch.input Auxillary Limit Switch.input
Cycle Time Open Alarm (CTOA ) Cycle Time Open Alarm (CTOA ) Cycle Time Open Alarm (CTOA )
Cycle Time Closed Alarm (CTCA) Cycle Time Closed Alarm (CTCA) Cycle Time Closed Alarm (CTCA)
Cycle Count Alarm (CCA ) Cycle Count Alarm (CCA ) Cycle Count Alarm (CCA )
CTOA | CTCA | CCA| TMPH|TMPL CTOA | CTCA | CCA| TMPH|TMPL CTOA | CTCA | CCA| TMPH|TMPL
Table 1:
DI Channel Parameter Settings List
DI Function Block DI Function Block DI Function Block
Channel = 6 Channel = 6 Channel = 6
6 6 6
7 7 7
PV_D PV_D PV_D
8 8 8
9 9 9 Is Closed Is Closed Is Closed
10 10 10 Is Opened Is Opened Is Opened
11 11 11 Is Stopped Is Stopped Is Stopped
12 12 12 Is Opening Is Opening Is Opening
13 13 13 Is Closing Is Closing Is Closing
1 1
2 2
OUT_D OUT_D OUT_D
3 3
4 4
5 5
TM
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