Trane IntelliPak 2 Series, Инструкция по установке, эксплуатации и обслуживанию

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20 RT-SVX24Q-EN
Figure 11. Control module locations
BCI
eFlex™ Variable Speed Compressor Staging
N No otte e:: The eFlex™ variable speed compressor can be
manually controlled only in service test mode
through the Intellipak controller human interface.
The TRV200 inverter keypad has been
programmed purposely to provide stop, reset,
and diagnostics functions only. This is to prevent
bypass of compressor protection functions
provided by the Intellipak control logic.
The figure below generally describes how the IntelliPak
controller sequences the eFlex™ variable speed
compressor as building load increases. It is assumed
that the unit is equipped with an economizer.
At low building loads, the economizer will often meet
the building load and compressor cooling will not be
required. Then as the building load increases and the
economizer no longer can maintain setpoint, the
IntelliPak controller sends a signal to the TRV200
inverter to start the variable speed compressor. The
TRV200 inverter ramps the compressor up to 50Hz for
10 seconds to ensure compressor start-up lubrication.
Control is released back to the IntelliPak controller and
the compressor runs at minimum speed command (0
VDC from VSM board).
Until the building load exceeds the variable speed
compressor capacity at minimum speed, the IntelliPak
compressor will cycle the variable speed compressor to
meet setpoint (4 minute minimum on/off time).
However, since variable speed unit minimum capacity
is about 15%, this transition cycling will be less than a
typical fixed speed compressor unit which may have
25% minimum capacity.
As the building load increases and eventually equals
the variable speed compressor capacity at minimum
speed, the compressor will run continuously and no
longer cycle. Then as the building load increases, the
IntelliPak controller will increase compressor speed to
meet the setpoint. When the variable speed
compressor eventually reaches maximum speed and
more capacity is required, a fixed speed compressor is
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