Hitachi RAS-10HRNM, Service Manual, Page: 172 / 482

These signals are set up through the PCB of the outdoor unit.
• Input signals
Ind. Input signal Application Port
0
N° setting application N° setting —
1 Fixing the heating mode
This signal allows to pre-fix the operation mode, in this case the heating mode,
independently of what the indoor unit requests. If the indoor units request the
oposite mode than the outdoor unit, the compressor will not start. This is very
useful to set up a unique operation mode.
CN1 and CN2
2
Fixing the cooling mode
This signal allows to pre-fix the operation mode, in this case the cooling mode,
independently of what the indoor unit requests. If the indoor units request the
oposite mode than the outdoor unit, the compressor will not start. This is very
useful for computer rooms where the cooling mode is fixed throughout the year.
CN1 and CN2
3 Demand thermo OFF
This signal allows to stop the compressor if it reaches a certain power as well
as to put the indoor unit in Thermo-OFF. This is very useful for installations
with high power consumption.
CN1 and CN2
4
Forced stoppage
This signal allows to control the stoppage of the compressor and the fans of
the indoor as well as outdoor units. This is very useful when used with the alarm
signals of the fire prevention systems.
CN1 and CN2
5 Current control demand 50%
This signal allows to regulate current consumption and establish an average
consumption of 50% of the rate point. This is very useful for installations that
run 24 hours a day.
CN1 and CN2
6
Current control demand 75%
This signal allows to regulate current consumption and establish an average
consumption of 75% of the rate point.This is very useful for installations that
run 24 hours a day.
CN1 and CN2
7 Current control demand 100%
This signal allows to regulate current consumption and establish an average
consumption of 100% of the rate point. This is very useful for installations that
run 24 hours a day.
CN1 and CN2
• Output signals
Ind. Output signal Application Port
0
N° setting application N° setting —
01 Operation signal
This signal allows to pick up the machine’s operation signal. This is very useful
to start up additional systems such as humidifiers, fans and other additional
air-conditioning systems.
CN7
02
Alarm signal
This signal picks up the machine’s alarm. This is very useful to warn that an
alarm has been tripped.
CN7
03
Compressor ON signal
This single allows to pick up the compressor’s operation signal. It is very useful
for checking signals during remote-control operation and for the interlock of
the outdoor unit.
CN7
04 Defrost operation signal
This signal allows to pick up the defrosting of the unit. This is very useful to
know how the indoor unit is operating if there is an abnormal situation.
CN7
N O T E
• Do not set same function (01-04) to multiple input port.
Programming
The optional signals are programmed through the PCB of the outdoor unit.
Setting of the optional signals
Setting of the optional signals The optional signals of the outdoor unit are set up from the PCB of the outdoor unit and push
switches PSW1, PSW2 and PSW3
6 Optional functions
164
SMGB0060 rev. 1- 12/2010