Future Design MCTB 4.3, User Manual

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MCTB
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The
DC power supply output function must be selected when the output type ordered for the limit control is a
transmitter power supply.
The
Alarm output function activates the alarm configuration settings for assigning the type of alarm logic to
apply to output 2. When the alarm condition is active, the output will turn on.
The
Limit annunciator function uses output 2 as a means for activating an external audible alarm. When the
limit output deactivates due to the process value exceeding the high or low limit set point, output 2 will also
activate. The output will remain activate until the reset button is pressed on the Alarm screen in the runtime
application or the remote reset is activated.
4.3.13 Alarm Function
The Alarm Function is used to select the alarm type for output 2 if the output function is configured as an alarm
output. The alarm selections are mutually exclusive, i.e., selecting one will turn off the other. Once the desired
alarm type has been selected, press the “Done” button to set the alarm function for the limit control output and
return to the main Limit Configuration screen.
NOTE: For the following alarm descriptions, PV = process value, ASP is the alarm set point and AHY is the
alarm hysteresis.
When
Process value high alarm is selected and the process value is higher than the alarm set point (PV >
ASP), a process high alarm occurs. When the process value is lower than the alarm set point minus the alarm
hysteresis (PV < ASP
–AHY), the alarm is off.