Terminal Resistor Setting - Fujitsu AJ 126LELDH Series Design & Technical Manual

1-6. Terminal resistor setting

CAUTION
• Be sure to set the terminal resistor according to specifications.
• Set the terminal resistor for every network segment (NS).
– If terminal resistor is set in multiple devices, the overall communication system may be dam-
aged.
– If terminal resistor is not set in a device, abnormal communication may occur.
The layout of the switches differs by the type of the indoor unit. For the details, refer to
indoor unit PCB" on page 07-74.
NOTES:
• Be sure to set one terminal resistor in a network segment. You can set the terminal resistor at
the outdoor unit or signal amplifier.
• When setting the terminal resistor of a signal amplifier, refer to the installation manual of the sig-
nal amplifier.
• When setting multiple terminal resistors, take note of the following conditions:
– How many network segments are there in a VRF system?
– Where will you set the terminal resistors in a network segment?
(Condition for 1 segment: Total number of outdoor units, indoor units, and signal amplifiers is
less than 64, or the total length of the transmission line is less than 500 m)
– How many outdoor units are connected in 1 refrigerant system?
Based on the conditions mentioned above, set the outdoor unit DIP switch SET5-4 in accor-
dance with the table below.
DIP switch SET5-4
Off
On
¢ Setting example
NS (Network segment ) 1
Terminal resistor: On
Terminal resistor: Off
Terminal resistor: On
NS2
1-6. Terminal resistor setting
Refrigerant system 1
Master
Refrigerant system 2
Master
Refrigerant system 3
Master
NS3
Terminal resistor
Disabled
Enabled
- (07-63) -
"Setting on
Factory setting
Terminal resistor
settings:
Outdoor unit
(Master unit)
: On
: Off
Signal amplifier
Install
Do not install
NS4
1. System settings