Future Design MCT-CM, Руководство пользователя

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MCT-CM
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For example, if digital output 2 is used as the control output for the system fans when a system event is turned
on, then select digital output 2 from the list. This will turn off the fans during defrost and precool whenever the
defrost cycle is active. Additional outputs can be selected if necessary. Once all selections have been made,
press the ‘Done’ button to accept the defeat selections and return to the Defrost Setup screen.
4.6 Redundancy Setup
The Redundancy Setup screen is accessed from the
“Options” menu and allows the OEM to configure the type
of redundancy mode to use (if any) and what alarm and outputs are to be associated with redundancy operation.
Redundancy provides the OEM with a means for configuring the MCT to control two separate systems, usually
identical, where one is a primary system and the other is a back-up system in case of primary system failure.
The redundancy settings provide selections for the type of back-up system operation as well as selections for
alarm inputs and redundancy enable settings.
NOTE: See section 9.2 Redundancy for a more detailed explanation of redundancy operation.
The
Redundant Mode selection is used to choose how redundancy operates. Available selections are
Disabled, Concurrent and Alternating. The concurrent and alternating redundancy modes select the back-up
system mode of operation. When concurrent is selected, both system 1 and system 2 will operate at the same
time when the selected alarm source in is alarm. When alternating is selected, the MCT will switch to the back-
up system on alarm.
The
Defrost Switching action is used to select how the redundant systems will switch if defrost is also enabled.
Available selections are Before Defrost, After Defrost and Low Rise Backup. When before defrost is selected,
the systems will alternate based on the defrost interval setting without actually running a defrost cycle. When
after defrost is selected, the currently running system will perform a defrost cycle prior to switching to the other
system. When low rise backup is selected, the backup system will turn on and operate while the primary system
is in defrost.