Daikin EUWAC8FZW1, Installation And Operation Manual

EUWAC5~10FZ

Packaged air-cooled water chillers

4PW14037-1D

Installation and operation manual

6

Safety devices

In its standard version, the unit is equipped with the following safety
devices:

■

Overcurrent relay (general safety device)
The overcurrent relay (K4S) is located in the switch box of the
unit and protects the compressor motor in case of overload,
phase failure or too low tension. The relay is factory-set and may
not be adjusted. When activated, it must be reset manually.

■

High-pressure switch (general safety device)
The high-pressure switch (S1HP) is installed on the discharge
pipe of the unit and measures the condenser pressure (pressure
at the outlet of the compressor). When the pressure is too high,
the pressure switch  is activated and the unit stops. 
The switch is factory-set and may not be adjusted. The switch
resets automatically, but the controller needs to be reset
manually.

■

Low pressure switch (general safety device)
The low-pressure switch (S4LP) is installed on the suction pipe
of the unit and measures the suction pressure (pressure at the
inlet of the compressor). When the pressure is too low, the
pressure switch  is activated and the unit stops.
The switch is factory set and may not be adjusted. The switch
resets automatically, but the controller needs to be reset
manually.

■

Reverse phase protector (general safety device)
The reverse phase protector (R1P) is installed in the switch box
of the unit. It prevents the compressor from running in the wrong
direction. If the unit does not start, two phases of the power
supply must be inverted.

■

Discharge thermal protector (general safety device)
The discharge thermal protector (Q*D) is activated when the
temperature of the refrigerant leaving the compressor becomes
too high. When the temperature returns to normal, the protector
resets automatically, but the controller needs to be reset
manually.

■

Fan motor thermal protector (part safety device)
The fan motor is equipped with a thermal protector (Q11F). The
protector is activated when the fan motor temperature becomes
too high.
When the temperature returns to normal, the protector resets
automatically.

■

Outlet water temperature sensor (general safety device)
The outlet water temperature sensor (R4T) measures the
temperature of the water at the water heat exchanger outlet. The
protection device shuts down the circuit when the temperature of
the chilled water becomes too low in order to prevent freezing of
the water during operation. 
When the outlet water temperature returns to normal, the
protector resets automatically, but the controller needs to be
reset manually.

■

Additional interlock contact (general safety device)
To  avoid that the unit could be started or run without water
circulating through the evaporator, an interlock contact (S10L) of
e.g. a flow switch must be switched in the start-up circuit of the unit.

Measuring devices

Checking the high and low pressure of the refrigerant circuit is neces-
sary to ensure the proper operation of the unit and to guarantee that
the rated output will be obtained. The unit has therefore been
equipped with a high and low pressure gauge. Refer to the checklist
in the chapter 

"Switching the EUWAC unit on" on page 8

.

■

High pressure gauge
The high pressure gauge indicates the discharge pressure
(pressure at the outlet of the compressor).

■

Low pressure gauge
The low pressure gauge indicates the suction pressure
(pressure at the inlet of the compressor).

Internal wiring - Parts table 

Refer to the internal wiring diagram sticker on the unit. 
The abbreviations used are listed below:

A1P .................... PCB: Terminal unit

A2P ............ **.... PCB: Adress card (for optional BMS)

A3P .................... PCB: Fanspeed controller (5 Hp only)

C1 ...................... Capacitor for fanmotor

E1H .................... Crankcase heater

F1,2,3U ...... #..... Fuses

F5B .................... Fuse for control circuit

F7B .................... Fuse for fan circuit

F9B .................... Fuse for secondary of TR1

F8U .................... Surge-proof fuse

F9U ............ ##... Surge-proof fuse (for optional BMS)

H1P ............ * ..... Indication lamp alarm 

H3P ............ * ..... Indication lamp operation compressor 

K1M.................... Compressor contactor

K4S .................... Over current relay

K1A .................... Auxiliary relay for high pressure

K1F,K3F ............. Contactor for high speed selection of the fan motor

(8+10 Hp only)

K2F .................... Contactor for low speed selection of the fan motor

(8+10 Hp only)

KP .............. * ..... Pumpcontactor

M11F.................. Fan motor

M1C ................... Compressor motor

PE ...................... Main earth terminal

Q1D.................... Discharge thermal protector

Q11F .................. Fan thermal protector

R1P .................... Reverse phase protector

R3T .................... Inlet water temperature sensor

R4T .................... Outlet water temperature sensor

S1HP.................. High pressure switch

S4LP .................. Low pressure switch

S4PC.................. Head pressure switch for fanspeed control 

(8+10 Hp only)

S9S ............ * ..... Switch for remote start/stop

S10L........... #..... Flowswitch

S11L........... #..... Contact that closes if the pump is working

S12S .......... #..... Main isolator switch

TR1 .................... Transfo 230 V 

➞ 

24 V (30 VA) for power supply of

controllers

X1....................... Connector in terminal unit for digital inputs, analog

inputs, analog outputs and for power supply
controller

X2....................... Connector in terminal unit for digital outputs

Not included with standard unit

Not possible as option

Possible as option

Obligatory

#

##

Not obligatory

*

**