Hitachi RAS-(4-12)HNP(1)(E) - Description of Optional Signals; Input Signals

6 Optional functions
168
SMGB0087 rev.0 - 12/2013
6.1.4 Description of optional signals

Input signals
N O T E
Inbracketscontrolfunctionnumbers.
a. Fixingoperationmode(heating/cooling)(1/2)
This input function is xed in terminals CN1 or CN2 of the PCB of the outdoor unit, to use it as a cooling and heating mode.
CN1 must be set up as follows.
Short circuit between the terminals 1 and 2 of CN1: set heating mode.
Short circuit between the terminals 2 and 3 of CN1: set cooling mode.
After having pre-xed the established mode, the remote control can only be used to adjust the temperatures. Stoppage
code “d1” “20” will be displayed if an attempt is made to change the operation mode of any of the indoor units with the
remote control.
Example of wiring diagram of xing the operation mode.
A
Outdoor unit PCB
• A: 3P connector cable.
• X1: Cooling.
• X2: Heating.
• SS1: Fixing operation mode switch.
• SS2: Change over switch
b. DemandthermoOFF(3)
This is an input function to control the maximum power that the compressor can consume. When this option is turned on,
the outdoor units are stopped completely, and the indoor units go into thermo-OFF. Alarm “10” is displayed on the remote
control. If the switch of this function is disconnected it becomes available again.
Connect the cabling and use the materials as shown in”6.1.1Availableports”.
N O T E
Forsingleconnection(onlyforcoolingorheatinginputsignal),thissettingisnotrequired.
c. IntermittentOperationofoutdoorfan(4)for(RAS-(4-6)H(V)C1Eonly
This is an auxiliary function to protect the outdoor unit from snow. When the input terminals for “Intermittent Operation of
Outdoor Fan Motor” on the outdoor unit PCB are short-circuited during the compressor stoppage, all the outdoor fan motors
start operating. If the compressor restarts operating, the outdoor fan motors will be restored to normal operation. If the input
terminals of “Intermittent Operation of Outdoor Fan Motor” are opened during the outdoor fan motor operation following
the short circuit of these terminals, the outdoor fan motor will stop.This function is available only during the compressor
stoppage (during the compressor power-ON or thermo-OFF). Therefore, this function will not be available even if the input
signal is sent during the normal cooling or heating operation.