Future Design MCT-CM, Руководство пользователя

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MCT-CM
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10.5.1 Remote Set Point Operation
Once an input is configured for loop set point control, as the analog input signal is varied, it will provide a linear
set point change from the minimum to maximum value over the range of the input (2-10Vdc for voltage input
and 4-20mA for current selection).
Signals below 2Vdc for the voltage input type, and below 4mA for the current input type, will disable remote set
point control so that the loop set point can be changed manually at the MCT. It also prevents the remote set
point control from setting a false input if the signal wires are cut or the signal is lost from the remote set point
source device.
NOTE: When remote set point control is activated, it will override the local set point as well as the ramp/soak
program set point if a program is running. Once deactivated, the loop set point will return to the
previous local set point of the loop, i.e., the value prior to the remote set point being activated and
taking control of the loop
’s set point, or the current program set point if a program is running.
If the minimum or maximum range exceeds the set point limits for the loop as set in the MCT
configuration, the MCT will limit the set point to the minimum or maximum value as defined under the
loop’s configuration.
10.6 Analog Outputs
The MCT can support up to 7 analog outputs which can be used to retransmit set points, process variables or
percentage of output from the installed control loops. Each of the available analog outputs can be configured
from the ‘Analog Output’ screen.
The left and right navigation buttons at the upper right of the screen allow the user to scroll through each
available output. To make changes to the output’s configuration, select the desired output type by pressing the
voltage (Vdc) or current (mA) button to select a 0-10V or a 4-20mA input signal.
NOTE: If the analog output type is changed from voltage to current or vice versa, power must be cycled to the
MCT controller in order for the output to switch types.
Select the desired source loop by pressing the ‘Source’ select button to choose from the list of available control
loops. Select the desired control loop and press the ‘Return’ button to return to the Analog Output screen.