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R410a tropical air-cooled scroll chiller unit 60Hz MCAC-ATSM-2014-09
84 Control system
7
Spot check. The operating status of outdoor system can be observed through spot check, and specific display
contents are as shown in the following figure:
Normal display
Operating mode
Operating capability of the compressor B
Number of online units
Outdoor ambient temp. Temp. of the condenser A
T61 frost-proof temp
Unit outlet water temp
Unit outlet-water tempe
Temp. of the condenser B
EXV opening A
EXV opening B
Operating current of system A
Operating current of system B
The last failure
● Display contents of “operating mode”: 1. cooling; 2. heating; 4. pump; 8. Stand-by
● Display contents of “number of online units”: the main unit can display the number of online units, and the
subordinate unit displays 0.
8 Selection code of the compressor
9
10 COM (O) 485 communication port (fault code E2)
11
COM (I) 485 communication port (fault code E2)
COM (O) is interconnected with P, Q and E of COM (I), used for RS-485 communication.
1) If faults occur between the wired controller and the main unit module, all modules will be shut down.
2) If faults occur between the main unit and subordinate units, the subordinate unit module suffering communication
fault will be shut down. Less units will be detected by the wired controller, which may display EA, and in the
meanwhile, the indicator lamp of the wired controller will flash. Restart 3 minutes later after malfunction be removed.
12
high-pressure protection of the system A and discharge temperature switch protection (protection code P0);
high-pressure protection of the system B and discharge temperature switch protection (protection code P2);
low-pressure protection of the system A (protection code P1);
low-pressure protection of the system B (protection code P3);
Constant speed compressor: connection of discharge temperature switch and high-pressure switch of the system in
series.
13 Inlet water temperature sensor T62 (TBH2) (fault code EF)
14 Shell and tube low-temperature ant-freeze sensor T61 (TBH1) (fault code Eb)
15
Water flow detection (fault code of the main unit E0) is only valid for the main unit but invalid for subordinate units.
1) Main unit: if abnormal water flow occurs for the first and second time, the main unit board will display fault code E9.
If abnormal water flow occurs the third time, the main unit board will display fault code E0 (off-power recovery is
needed), and the wired controller will display fault code E0 (fault is displayed only after 3 detection).
2) Subordinate unit: (water flow detection will not be done).
16 Control port (reserved)
17 Electronic expansion valve of the system B
18
Electronic expansion valve of the system A
Electronic expansion valve is used to control refrigerant flow under different operating modes and different loads.
19
Auxiliary electric heater
Attention: the control port value of auxiliary electric heater actually detected is ON/OFF but not 220-230V control
power supply, so special attention should be paid when installing the auxiliary electric heater.
Attention!
Under heating mode, when the main unit board detects total water outlet temperature to be lower than 45
℃
, the switch
will be closed, and the auxiliary electric heater will begin to work; when the total water outlet temperature is higher than
50
℃
, the switch will be opened, and the auxiliary electric heater will stop working.
Each modular part of modular unit has the same electric
control function, and the main unit and subordinate units
can be set through address code on the electric control
board. The address code 0 # is provided as the main unit.
The priority of being the main unit is given to the unit with
digital compressor, and other addresses are subordinate
units. Only the unit is chosen as the main unit, its electric
control
can
activate
such
functions
as
direct
communication with the wired controller, refrigerating and
heating capability adjustment, pump control, auxiliary
electric heater control, total effluent temperature detection
and water flow switch detection.
When the address is 0,
it serves as the main
unit.
When the address is
1,2,3……F, it serves as
the subordinate unit
1,2,3……15.
8
9
A
B
C
D
E
F
8
7
6
5
4
3
2
1
0
0 1
2
3
4
5
6
7
8
F
E
D
C
B
A
9
8
ADDRRSS
Summary of Contents for MGBT-D25W/DN1
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