Dunham-Bush ACXi 165-5SP-LN, Инструкция по установке, эксплуатации и обслуживанию

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4.0 ELECTRICAL
4.1 ELECTRICAL DATA
ACXI Unit Data Compressor Fan Motors
Model
ACXi
Electrical
Spec.
V- PH- Hz
Min Circuit
Ampacity
(A)
Max
Branch
Fuse Size
(A)
Qty. Model RLA
Each
(A)
LRA
Each
(A)
Qty. Hp
Each
(A)
FLA
Each
(A)
165-5SP-
LN
400 - 3- 50 440A 600A 1
1 MSC 1210
MSC 1212 163
202 995
1050
12 0.5 2.0
4.2 WIRING DIAGRAM
Figure 4.2 are typical wiring diagrams for a 2
compressor unit. This may not be an accurate
representation of your unit. It is best to use the
wiring diagram mounted in the package control
panel. A copy of that diagram is furnished with
the unit owner’s manual.
4.3 TYPICAL OPERATION
In order to start a compressor, the following
conditions must be met:
- Phase Control Relay (PCR) setting
- Chilled water pump running
- Chilled water flow switch made
- Compressor circuit breakers on
- Customer unit control contact closed
- Control switch and compressor switches on
- Reset pressed on microcomputer keypad
- Power has been on the microcomputer for 15
minutes
- All safety conditions satisfied
- Leaving chilled water temperature 2°F or more
above setpoint
A compressor is started by first energizing 1M1
followed by 1M2. Anti-recycle time of 15
minutes is initiated within the computer at start.
When the compressor starts, the microcomputer
monitors amperage by means of 1CT, voltage
using 3T, leaving water temperature using TS,
and condensing pressure. These inputs are used
to control the loading and staging of the
compressor. The compressor's loading is
controlled by pulsing signals to the load and
unload solenoids.
If the safety conditions are satisfied for the #2
compressor, at least 1 minute has elapsed since
starting #1 compressor, and leaving water
temperature remains above the deadband; 2M1
and 2M2 will be activated by the micro-
computer, #2 compressor also has a 15 minute
antirecycle timer built into the microcomputer.
Loading of the #2 compressor is controlled the
same as compressor #1.
To shut down the unit automatically, the
customer control contacts must be opened. To
shut down the unit manually, simply shut off the
compressor switches. This will cause a no-run
alarm that must be reset to restart the
compressor.
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