EWAP110~340MBYNN
Packaged air-cooled water chillers
4PW22677-1
Operation manual
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2
Circuit safety devices
Circuit safety devices shut down the circuit they protect. For this
reason the unit does not need to be manually put on again after
a circuit safety occurred.
3
Part safety devices
Part safety devices shut down the part they protect.
An overview of all safety devices is given below.
■
Overcurrent relay
The overcurrent relays (K*S) are located in the switchbox of the
unit and protect the compressor motors in case of overload,
phase failure or too low voltage. The relays are factory-set and
may not be adjusted. When activated, they must be reset
manually, followed by a reset of the controller.
■
Compressor thermal protectors
The compressor motors are equipped with thermal protectors
(Q*M). The protectors are activated when the compressor motor
temperature becomes too high.
When temperature returns to normal, the protectors reset
automatically, but the controller needs to be reset manually.
■
Fan motor thermal protector
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.
■
Flowswitch
The unit is protected by a flowswitch (S8L).
When the waterflow becomes lower than the minimum allowed
waterflow, the flowswitch shuts down the unit. When the
waterflow becomes normal, the protection resets automatically
but the controller still needs to be reset manually.
■
Discharge thermal protectors
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.
■
Freeze-up protection
The freeze-up protection prevents the water in the evaporator
from freezing during operation. When the outlet water
temperature is too low, the controller disables the unit. When the
outlet water temperature returns to normal, the unit can start up
again.
When freeze-up protection occurs several times in a certain
period, the freeze-up alarm will be activated and the unit will be
shut down. The cause of freezing up should be investigated and
after outlet water temperature has risen enough, the alarm
indicator on the controller needs to be reset manually.
■
Low pressure safety
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
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.
■
High pressure switch
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
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............... **........ Current transfo/A-meter
A1P ........................ PCB controller
B1P ........................ Low pressure transmitter
B2P ........................ High pressure transmitter
C1~C3.................... Capacitor
E1HC ..................... Crankcase heater compressor
E3H ........................ Evaporator heater
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 for A1P
F9B ........................ Fuse for secondary of TR2
F12B,F14B............. Fuse for fanmotors
H1P ............ * ......... Indication lamp general operation
H2P ............ * ......... Indication lamp alarm
H3P ............ * ......... Indication lamp operation compressor
H5P ............ * ......... Changeable output
J1 ........................... Power supply
J2,J3,J6.................. Analog input
J5,J7,J8.................. Digital input
J11 ......................... RS485 connection
J12~J18 ................. Digital output
K1M........................ Linecontactor
K2M........................ Deltacontactor
K3M........................ Starcontactor
K7F~K9F................ Fancontactor
K17S ...................... Overcurrent relay
K1A ........................ Auxiliary relay for safeties
K2A ........................ Auxiliary relay compressor thermal protector
K3A ........................ Auxiliary relay for discharge thermal protector
K7A ........................ Auxiliary relay for safety of high pressure
L1~L3 ..................... Main supply terminals
M11F-M18F ........... Fan motors
M1C ....................... Compressor motor
M1S........................ Stepless capacity control for compressor
PE .......................... Main earth terminal
Q11F-Q18F............ Thermal protectors fan motors
Q1M ....................... Thermal protector compressor motor
R1 .......................... Auxiliary resistence for feedback (R1F)
R1F ........................ Feedback resistance
R1P ........................ Reverse phase protector
R3T ........................ Sensor for evaporator inlet water temperature
R4T ........................ Sensor for outlet water temperature
R5T ........................ Sensor for ambient temperature
R8T ........................ Sensor for evaporator outlet water temperature in
a DICN system
S1PH...................... High pressure switch
S3T ........................ Discharge thermal protector
S5E ........................ Emergency stop push button
S6S ............ * ......... Changeable switch for remote function
(e.g. remote start/stop)
