Future Design MCTB 4.3, Руководство пользователя

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MCTB
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The
Math/logic input only function allows the event input to be used as an input for math/logic equations only.
See section 4.6 Math/Logic Configuration for more information.
NOTE: In order for the alarm and annotation input functions to operate properly, the input must be activated
for at least five seconds. If the input is not activated for the minimum time period, the input status
may not be captured and the alarm or annotation will not be posted. In order for the input to reset
and capture the next input status, the input must also remain off for at least five seconds.
The
Initialize ramp rate setpoint to PV function
(MCTB 4.3” version 4MA V1.3 only)
is utilized in conjunction
with the loop ramp rate option (see section 4.2.36 Ramp Rate Operation ). When ramp rate operation is enabled
for the loop, activating the input (off to on transition) will reset the current loop set point to the PV value. The
loop set point will then continue ramping from the current PV value to the ramp rate target set point according
to the programmed ramp rate.
The
Ramp rate hold function
(MCTB 4.3” version 4MA V1.3 only)
utilized in conjunction with the loop ramp
rate option (see section 4.2.36 Ramp Rate Operation ). When ramp rate operation is enabled for the loop,
activating the input will pause the set point ramp and hold the loop set point at its current value. Deactivating
the input will allow the loop set point to continue ramping from its current value to the ramp rate target set point
according to the programmed ramp rate.
The
Activate SP2 function
(MCTB 4.3” version 4MA V1.3 only)
enables a secondary set point for the loop (see
section 4.2.40 Setpoint 2 ). When activated, the current loop set point is overridden and the configured SP2
value is used as the loop set point. When the input is deactivated, the loop set point returns to the previous
user entered set point
NOTE: When SP2 is activated, it will override the loop set point even if an automatic ramp/soak program I in
operation. When the input is deactivated, the loop set point will return to the set point as determined
by the running program at the time the input is deactivated.
4.2.8 Event Input Alarm Message/Annotation
When the event input function is set to alarm input or data logging annotation, the Event Input Alarm
Message/Annotation entry allows the user or OEM to assign the message that will be shown on the alarm
screen in the runtime application for alarm operation, or the operator event that will be written to the data log
file for annotation operation. The message can be up to 25 characters long.
4.2.9 Low/High Limit Setpoint
The low and high limit set points are used to set the minimum and maximum allowed set points that can be
entered for the loop control. These are typically set by the OEM to limit the control range to within the safe
operating range of the equipment.
NOTE: The runtime application provides additional user low and high set point limits (see section 9.3 Setpoint
Limits ). These can be adjusted to further limit the allowable set point range within the band set by
the OEM low and high limit set points. By default, the user set point limits are zero. The user set
points must also be adjusted in the runtime application in order to allow proper set point entry.
4.2.10 Output 1 Function
The Output 1 Function is used to set the mode of operation for the primary control output of the loop control
board. The output can be set for heating or cooling on/off control, time proportioning or linear control. The
output 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 output function for the loop control board and return to
the main Loop Configuration screen.