Future Design MCTB 4.3, Руководство пользователя

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MCTB
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To utilize this mode of operation, typically both the control outputs of the outer loop and
inner loop are wired to the final control elements. The outer loop would control the valve
for water flow, while the inner loop would control the valve for additive flow. This allows
the operator to adjust the water flow as required for downstream processes and the inner
loop will automatically adjust the required additive flow based on the actual water flow
rate.
If in this example the water flow rate is controlled by another process, the outer loop
would not be wired and its set point value would not be utilized. The inner loop set point
is determined solely by the actual process value of the outer loop.
The
Cascade Control Inner Loop and Cascade Control Outer Loop drop down menus provide a current list
of all configured loops (by tagname). This allows the inner and outer loops to be selected according to the
desired loop order. Note that both inner and outer loop cannot be set to the same loop. If the same loop is
selected, cascade control will not operate. Once loop must be selected as the outer loop to drive the set point
of the inner loop.
4.8 Expansion IO Module Option
The Expansion IO Configuration screen is accessed from the Options menu. The screen allows the option to
be enabled/disabled and also provides access to all input and output function settings for the expansion IO
module.
To view all of the available settings, the Expansion IO must be set to “Enabled”. When enabled, the
configuration items for each input and output will then be provided in the list. Simply swipe up or down on the
screen to scroll through the list items. To edit a value, tap the row for the desired item.
4.8.1
Input (8-23) Function
The input function is used to select the desired mode of operation for each digital input. Each input is provided
with its own function selection. The input numbers correspond to the markings on the expansion IO module.
The input selections are mutually exclusive, i.e., selecting one will turn off the others. Once the desired function
has been selected, press the “Done” button to set the input function for the selected expansion module input
and return to the main Expansion IO Configuration screen.