CVGF-SVU02B-E4
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If the chiller approaches full
current, the evaporator
temperature drops too low, or
the condenser pressure rises too
high, Tracer CH530 Adaptive.
Control logic limits the loading
of the chiller to prevent the
chiller from shutting down on a
safety limit. These limits may
prevent the chiller from reaching
the load requested by the Base
Loading signal.
Base Loading Control is basically
a variation of the current limit
algorithm. During base loading,
the leaving water control
algorithm provides a load
command every 5 seconds. The
current limit routine may limit
the loading when the current is
below setpoint. When the
current is within the deadband of
the setpoint the current limit
algorithm holds against this
loading command.
If the current exceeds the
setpoint, the current limit
algorithm unloads.
The “Capacity Limited By High
Current” message normally
displayed while the current limit
routine is active is suppressed
while base loading.
Base loading can occur using
Tracer or an external signal.
Tracer or an external signal Base
Loading: Current Setpoint
Range: (20 - 100) percent RLA.
Base Loading requires Tracer
Summit and an optional Tracer
Communications Module (LLID)
Base Loading Control
Algorithm
This feature allows an external
controller to directly modulate
the capacity of the chiller. It is
typically used in applications
where virtually infinite sources
of evaporator load and
condenser capacity are available
and it is desirable to control the
loading of the chiller. Two
examples are industrial process
applications and cogeneration
plants.
Industrial process
applications
might use this feature to impose
a specific load on the facility’s
electrical system.
Cogeneration plants
might use
this feature to balance the
system’s heating, cooling and
electrical generation. All chiller
safeties and adaptive control
functions are in full effect when
Base Loading control is enabled.
Base Loading
Control Algorithm
Summary of Contents for CVGF 1000
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