Future Design MCT-CM, User Manual

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MCT-CM
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NOTE: If defrost is disabled in the MCT
configuration and redundancy is enabled, you must select ‘After
Defrost’ in order to activate equal run time switching. Alternating time settings will not be activated in
the MCT runtime application unless it is selected.
If equa
l run time switching is not required or desired, setting the defrost switching action to ‘before
defrost’ will prevent equal run time operation and the systems will only switch upon failure or when
the primary system is manually changed by the user in the MCT runtime application.
The
Alarm Source # field is used to enter the system alarm number that is to be used to activate the redundancy
back-up system. This allows the OEM to select any of the 30 process alarms available in the MCT (each alarm
is configurable in the MCT runtime application). This allows any loop or monitor point to activate the back-up
system on a high, low, high/low, deviation or rate of change condition.
4.6.1 Setting the System 1/2 Alarm Inputs
The system 1 and system 2 alarm input selections allow the OEM to select which inputs should be used (if any)
for the system 1 and system 2 failure inputs. When the digital input is activated, the respective system would
be disabled and the other system would remain operating indefinitely until the alarm condition was corrected
on the other system.
Alarm inputs do not have to be configured; however, when configured, the selected input(s) must be configured
as an alarm input under the Digital Input Setup of the MCT runtime application. To select alarm inputs for
system 1 and/or system 2, press the
“System 1 Alarm Inputs” or “System 2 Alarm Inputs” button.
For example, if digital input 1 will be used for the system 1 failure input, then select digital input 1 from the list.
If digital input 2 will be used for the system 2 failure input, select it as the alarm input for system 2. Additional
inputs can be selected if necessary.
Once all selections have been made, press the ‘Done’ button to accept
the input selections and return to the Redundancy Setup screen.
4.6.2 Setting the Redundancy Enable Outputs
In order for redundancy to operate, concurrent or alternating, an output must be selected as an enable for the
redundancy logic. When the output is on, the redundancy logic is activated and any digital outputs configured
in the MCT runtime application under Digital Output Setup as
“Redundant System 1” or “Redundant System 2”
will activate based on the redundancy mode of operation.
This allows the system 1 and 2 outputs to be turned on and off in conjunction with a common system that they
are associated with. There must be at least one output selected in order for redundancy to operate regardless
of the selected type. To select which output(s) is to be used, press the
“Enable Outputs” button.