EWAD120~340MBYNN
Packaged air-cooled water chillers
4PW22683-1
Operation manual
4
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Fan motor thermal protector (part safety devices)
The condenser fan motors are equipped with thermal protectors
(Q*F). The protectors are activated when the temperature
becomes too high. When temperature returns to normal, the
protectors reset automatically.
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Flowswitch (general safety devices)
The unit is protected by a flowswitch (S8L).
When the water flow becomes lower than the minimum allowed
water flow, the flowswitch shuts down the unit. When the water
flow becomes normal, the protection resets automatically but the
controller still needs to be reset manually.
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Discharge thermal protectors (circuit safety devices)
The unit is equipped with discharge thermal protectors (S*T).
The protectors are activated when the temperature of the
refrigerant leaving the compressor becomes too high. When the
temperature returns to normal the protector resets automatically
and the controller needs to be reset manually.
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Freeze-up protection (general safety devices)
The freeze-up protection prevents the water in the evaporator
from freezing during operation. When the outlet water
temperature is too low, the controller shuts down the unit. When
the outlet water temperature returns to normal, the controller
needs to be reset manually.
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Low pressure safety (circuit safety devices)
When the suction pressure of a circuit is too low, the circuit
controller shuts down the circuit. When the pressure returns to
normal, the safety device can be reset on the controller.
■
Pressure relief safety valve (general safety devices)
The safety valve is activated when the pressure in the refrigerant
circuit becomes too high. If this occurs, shut down the unit and
contact your local dealer.
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High pressure switch (circuit safety devices)
Each circuit is protected by two high pressure switches (S*PH)
which measure the condenser pressure (pressure at the outlet
of the compressor). They are installed in the compressor
housing of the circuit. When the pressure becomes too high, the
pressure switches are activated and the circuit stops.
The switches are factory-set and may not be adjusted. When
activated, they must be reset by means of a screwdriver. The
controller still needs to be reset.
■
Reverse phase protector (circuit safety devices)
The reverse phase protectors (R*P) prevent the screw
compressors from running in the wrong direction. If the
compressors do not start, two phases of the power supply must
be inverted.
Internal wiring - Parts table
Refer to the internal wiring diagram supplied with the unit. The
abbreviations used are listed below:
A1,A2..........** ....... Current transfo/A-meter for circuit 1, circuit 2
A1P........................ PCB controller
A11P...................... Expansion board controller
(only for EWAD240~340)
B1P,B4P................. Low pressure transmitter for circuit 1, circuit 2
B2P,B5P................. High pressure transmitter for circuit 1, circuit 2
C1~C3 ................... Capacitor
E1HC,E2HC .......... Crankcase heater compressor circuit 1, circuit 2
E3H,E4H................ Evaporator heater circuit 1, circuit 2
F1U~F3U
.......# ........ Main fuses
F4U,F5U .....# ........ Fuses for evaporator heater
F6B ........................ Fuse for primary of TR1
F7B ........................ Fuse for secondary of TR1
F8U........................ Surge proof fuse of TR1
F9B ........................ Fuse for secondary of TR2
F10S,F11S ............ Circuit breakers with fuses for circuit 1, circuit 2
(only for EWAD240~340)
F12B,F13B ............ Autofuse for fanmotors circuit 1, circuit 2
H1P ............ * ......... Indication lamp general operation
H2P ............ * ......... Indication lamp alarm
H3P,H4P..... * ......... Indication lamp operation compressor 1,
compressor 2
H5P ............ * ......... Changeable output
J1 ........................... Power supply
J2,J3,J6.................. Analog input
J4 ........................... Analog output
J5,J7,J8,J19........... Digital input
J11,J23 .................. RS485 connection
J12~J18,J21,J22.... Digital output
K1A,K4A ................ Auxiliary relay for safeties circuit 1, circuit 2
K2A,K5A ................ Auxiliary relay compressor thermal protector
circuit 1, circuit 2
K3A,K6A ................ Auxiliary relay for discharge thermal protector
circuit 1, circuit 2
K7A,K8A ................ Auxiliary relay for safety high pressure circuit 1,
circuit 2
K1M,K4M ............... Linecontactor for circuit 1, circuit 2
K2M,K5M ............... Deltacontactor for circuit 1, circuit 2
K3M,K6M ............... Starcontactor for circuit 1, circuit 2
K7F,K10F ............... Fancontactor for circuit 1, circuit 2
K8F,K11F ............... Fancontactor for circuit 1, circuit 2
K9F,K12F ............... Fancontactor for circuit 1, circuit 2
K17S,K18S ............ Overcurrent relay for circuit 1, circuit 2
L1,L2,L3 ................. Main supply terminals
M1C,M2C ............... Compressor motors circuit 1, circuit 2
M1S,M2S ............... Stepless capacity control for compressor
circuit 1, circuit 2
M11F-M14F ........... Fan motors circuit 1
M21F-M24F ........... Fan motors circuit 2
PE .......................... Main earth terminal
Q1M,Q2M .............. Thermal protector compressor motor circuit 1,
circuit 2
Q11F-Q14F............ Thermal protectors fan motors circuit 1
Q21F-Q24F............ Thermal protectors fan motors circuit 2
R1,R2..................... Auxiliary resistance for feedback
R1F,R2F ................. Feedback resistance fot circuit 1, circuit 2
R1P,R2P................. Reverse phase protector circuit 1, circuit 2
R3T ........................ Sensor for evaporator inlet water temperature
R4T ........................ Sensor for evaporator outlet water temperature
(only for EWAD120~170)
R5T ........................ Sensor for ambient temperature
R7T ........................ Sensor for mixed outlet water temperature
(only for EWAD240~340)
R8T ........................ Sensor for common leaving water in a DICN
system
S1PH,S2PH ........... High pressure switch circuit 1, circuit 2
S3T,S4T ................. Discharge thermal protector circuit 1, circuit 2
S5E ........................ Emergency stop push button
S6S ............ * ......... Changeable switch for remote function
(e.g. remote start/stop)
S8L......................... Flowswitch
S9L............. #......... Contact that closes if the pump is working
S10S .......... * ......... Changeable switch for remote function
(e.g. dual setpoint)
S11S .......... * ......... Changeable switch for remote function
(e.g. enable/disable capacity limitation 1)
S12S .......... * ......... Changeable switch for remote function
(e.g. enable/disable capacity limitation 2)
S13S .......... ##....... Main isolator switch
