Trane CVGF1000, Инструкция по установке, эксплуатации и обслуживанию

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Tracer Base Loading
The Tracer commands the chiller to enter the base load mode by setting the base load
mode request bit ON. If the chiller is not running, it will start regardless of the differen-
tial to start. While the unit is running in base loading, it will report that status back to
the Tracer. When the Tracer removes the base load mode request, the unit will continue
to run, using the normal chilled water control algorithm, and will turn off, only when
the differential to stop has been satisfied.
External Base Base Loading
The AdaptiView accepts 2 inputs to work with external base loading.
The binary input is at 1A18 Terminals J2-1 and J2-2 (Ground) which acts as a switch
closure input to enter the base loading mode. The second input, an analog input, is at
1A17 terminals J2-2 and J2-3 (Ground) which sets the external base loading setpoint,
and can be controlled by either a 2-10Vdc or 4-20mA Signal. At startup the input type
is configured.
The graphs in Figure 32 show the relationship between input and percent RLA. While
in base loading the active current limit setpoint is set to the Tracer or external base
load setpoint, providing that the base load setpoint is not equal to 0 (or out of range).
If it is out of range, the front panel current limit setpoint is used. During base loading,
all limits are enforced with the exception of current limit. AdaptiView™ displays the
message “Unit is Running Base Loaded.”
An alternative and less radical approach to Base Loading indirectly controls chiller ca-
pacity. Artificially load the chiller by setting the chilled water setpoint lower than it is
capable of achieving. Then, modify the chiller’s load by adjusting the current limit set-
point. This method provides greater safety and control stability in the operation of the
chiller because it has the advantage of leaving the chilled water temperature control
logic in effect.
The chilled water temperature control logic responds quicker to dramatic system
changes, and can limit the chiller loading prior to reaching an Adaptive Control limit
point.
CVGF-SVX03B-EN
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Base Loading Control Algorithm