Honeywell UDC 3300 사용자 설명서

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UDC 3300 Controller Product Manual

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Figure 5-3 is a block diagram of internal Cascade for a 2-loop controller.

PRIMARY LOOP

SECONDARY LOOP

 

•  Loop #2 must be the primary loop. 
•  Loop #1 must be the secondary (internal or slave) loop 

because all output forms exist on Loop 1. 

•  Loop #1 Remote Setpoint is fixed as loop #2 output.

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The UDC 3300 allows you to select high or low output override. Refer to
Section 3 - Configuration to select High or Low.

The following rules apply for high/low override:
• Only one physical output is required when override is enabled. It is the

output from Loop 1 because Loop 2’s internal output is routed through
the selector.

• Loop 2 output can also be available at all times if desired.
• In Manual mode, the Output may be overridden.

• Does not apply for Three Position Step Control.
• OTI on bottom display shows value of the internal Loop 1 output

before any override.

 The output of the unselected loop tracks the selected loop

to within 5 % when in Auto mode to eliminate windup. This tracking is
done in the direction opposite to the Override Select configuration; i.e., for
High Select, the unselected output tracks within 5 % of lower, and vice
versa.