Hitachi FSG Series, Technical Catalogue

Page: 19 / 424

SYSTEM DESCRIPTION
1
/5
Setting of End Terminal Resistance
Before shipment, No.1 pin of DSW10 is set at the “ON” side.
In the case that the outdoor units quantity in the same H-link
is 2 or more, set No.1 pin of DSW10 at the “OFF” side from
the 2
nd
unit. If only one outdoor unit is used, no setting is
required.
Setting of End terminal Resistance DSW10
Before Shipment Cancellation
ON
1 2
ON
1 2
Wide Operation Range
This unit has been designed for cooling operation under low
ambient temperatures down to -5 ºC.
This feature enables cooling to be obtained even in winter
on buildings with high internal heat gains due to lighting,
people and machines, particularly in areas such as shops,
lecture rooms, data processing areas etc.
And the heating operation under low ambient temperature
down to -15 ºC can be also performed.
n
Electronical capacity control
Precise Control with the wide Range Inverter
The compressor speed for Set-Free series outdoor unit is
controlled within a wide range of from 30Hz to 115Hz.
Therefore, smooth operation is available without frequently
using the ON/OFF control. This new wide range capacity
control can meet not only the needs of a wide space but
also a small space such as guest rooms and management
rooms. Defrosting operation can be quickly performed
because of a high compressor speed of 70~75Hz.
Electronic Control
The capacity of the Outdoor unit is continuously controlled
by the inverter from 3.3% to 130%. This wide working range
has been obtained by the improvement of shaft strength and
high pressure oil circulation in the scroll compressor.
Therefore, an air conditioning system where heat load is
greatly changed through the day is easily catered for.
Also, the capacity of indoor unit is controlled by detecting
the inlet and set room temperatures using an inverter driven
compressor. Therefore even a small room can be air
conditioned without unwanted ON/OFF operation, resulting
in comfortable air conditioning.
Standard Unit
Inverter Driver Unit
RPI-0.8
(Director Room)
Less ON/OFF
Ensuring Comfort
Operation
RCI-2.5
(Office)
STOP
RCI-2.5
(Office)
STOP
RCI-2.5
(Office)
STOP
RCI-1.5
(Reception
Office)
STOP
Capacity Control
(8%:10HP of
outdoor unit
capacity) of Director
Room is still
possible.
Only for pull-down Operation
Outdoor Air
Wet Bulb
Temperature
(°C WB)
Outdoor Air
Dry Bulb
Temperature
(°C DB)
Indoor suction air Wet Bulb
Temperature (°C WB)
Indoor suction air Dry Bulb
Temperature (°C DB)
: Operation Control Range
Inlet Air Temperature
Outlet Air Temperature
Time
10 min.
Cooling Operation
(Setting Temperature
of Thermostat: 23 ºC
Cooling Operation
(Setting Temperature
of Thermostat: 23 ºC)
Inverter Frequency
Inlet Air Temperature
Outlet Air Temperature
Time
10 min.
Inverter Control of Set-Free System
(Example 10 HP)
115Hz
➠
30Hz (26%)
Œ
Improvement of
Shaft Strength
Wide
Operating
Range

High Pressure
Oil Circulation
8%