4 mA
20 mA
0 %
100 %
50 %
125 %
16.8 mA
For example, design feedrate = 10 lb/min, by setting the Full
value to 125% would set the 0 - 10 lb/min range equal to 4 -
16.8 mA
10 lb/min
Another example is if you want to scale the output from 0 – 7.5 lb/min over the full range
(4 – 20 mA). You would then set the full value to 75%.
4 mA
20 mA
0 %
100 %
50 %
7.5 lb/min
For example, design feedrate = 10 lb/min, by setting the f
value to 75% the 4 - 20 mA range would equal 0 - 7.5 lb/
min.
10 lb/min
Whenever you are using non-standard output scaling, you can see the actual output,
together with the underlying engineering value in Analog Diagnostics. See page 59.
Digital I/O Mapping
There are many logical inputs and outputs available. Normally, you will only use a few of
them for real connections. Furthermore, some logical inputs are set only once, since they
in reality are used for function configuration, and should always stay On or Off. The MC³
allows you to configure the digital inputs and outputs to your system’s requirements.
The MC³ I/O system operates on two layers, a physical and a logical. The physical layer
is connections to the outside world, for example relays or bits in a PLC. The logical layer
is function related. The logical outputs have names like
Rem Start Batch
and
Reset Total
.
The MC³ actually acts upon the logical layer.
The logical input layer is mapped to the physical input layer. It is possible to have one
physical input control one or more logical inputs. For example, one physical input can be
used to reset both Warnings and Faults.
The physical output layer is mapped to the logical output layer. It is possible to have one
or more physical output mapped to one logical output. For example, you may have to
start a vibrator when a Slow Fill condition occurs, and you also would like an indication in
the control room. You can map the
Slow Fill
logical output to two different physical
outputs, and then connect one to the vibrator and the other to the indicator.
The Alarm property allows you to qualify a logical input or output for a Warning or Fault.
When you do, the input or output name will be displayed in the Warnings (page 14) or
Faults (page 15) screen.
The inverting property allows you to invert (reverse the logic) of a physical output or
input, i.e. from “normally open” to “normally closed”.
The Force property allows you to override the status of a physical input or output to an
On or Off state. This is useful for troubleshooting.
35.00.EX O&M Manual
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Summary of Contents for MC3 35.00.EX
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