Carrier 50JC04-06, Инструкции по обслуживанию и техническому обслуживанию

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COMPRESSOR VFD
The 48/50JC units are equipped with a variable speed compressor.
To control this compressor a Variable Frequency Drive (VFD) is
required. This VFD does not look like the typical VFD the indus -
try might be used to. This VFD is not packaged into its own hous -
ing to appear as a single component, it is comprised of five elec -
tronic components mounted in the unit’s control box. See Fig. 49.
for the Control box layout. The five components are: The main
drive board, filter board, capacitor board, choke, and converter
board. On 575 volt units the filter board and capacitor board are
replaced with three-phase line reactor.
Drive Board
The drive board is the heart of the VFD. It contains the safety logic
and the power conversations needed for the variable speed
operation. This drive board will take in the 60 Hz supply voltage
and modify it to drive the speed of the compressor, this is done
with voltage and frequency. The drive board is responsible for
monitoring the safety high pressure switch (HPS) and ensure the
compressor is immediately turned off upon HPS trip. There is a
discharge line thermistor (DLT) also provided that the drive board
monitors. This is for situations where there are high line tempera -
tures without the pressure being high enough to indicate a
problem. The drive board has built in logic independent of the
SystemVu logic to fold back the speed of the compressor in the
event of a high current or high temperature situation. This high
current is determine based on the speed ranges, so not just one
current limit. The drive board has its own built in startup and
speed ramp protections, however these are smaller than what the
SystemVu controller uses. Review the Compressor Control sec -
tion for SystemVu controller start and ramp functions found in the
48/50JC 04-06 Ultra High Efficiency Single Package Rooftop
Units with SystemVu™ Controls Version X.X Controls, Start-
up, Operation and Troubleshooting Instructions manual. There
is a heat sink mounted on the back of this drive board to help cool
the electronics. The drive board only communicates via Modbus
and has local LEDs to show status and errors. The converter board
will be used as the primary interface to this drive board, so refer to
that section for more details. See Fig. 50 and Table 5 on page 28
for more details on the drive board.
Fig. 49 — Control Box Layout
CAUTION
UNIT DAMAGE HAZARD
Do not bypass the Drive board and pass the standard power
supply to the compressor, damage may occur.
CAUTION
UNIT DAMAGE HAZARD
If replacing the Drive board remove the whole assembly (heat
sink and electronic board together). Never separate this
assembly on the replacement part.
RS485
SENSOR
HPS
W
V
U
L1
L2
L3
GRN
DC- OUT
DC + OUT
BD 470 C JG
BD 470 C JG
BD 100 V J
G
BD 100 V J
G
BD 100 V J
G
BD 100 V J
G
BD 100 V J
G
BD 100 V J
G
BD 100 V J
G
HP 220 EJG HP 220 EJG
DC- IN DC + IN
W
arning Label
Model Label
SN Label
9D VZH 22 100V
Converter
Board
SystemVu Controller
TB4
PMR
Power
Supply
CCHR
IDMR
Capacitor
Board
Filter Board
Drive Board
Choke