HRX-OM-M090
Chapter 3 Transport and Setting Up
HRS Series
3.3
Installation
3-15
3.3.6
RS-485 Communication wiring
Serial communication RS-485, operation start/stop, setting and reading of
circulating fluid temperature, and reading of alarm condition can be done by
remote control.
Refer to the Communications Operation Manual for more details.
Wiring of interface communication cable
z
Connecting to PC
RS-485 cannot be directly connected to a normal PC. Use a RS-232C/RS485 converter which is
available on the market.
Be sure to follow the wiring procedure below for connecting multiple thermo-chillers.
z
Configuration of connection
One host computer : One thermo-chiller, or one host computer : N thermo-chillers.
(Max. 31 thermo-chillers can be connected.)
1
SD+
5
SG
9
SD-
SD+
SD-
SG
Terminal
resistance
Master
This product
(first slave)
1
SD+
5
SG
9
SD-
This product
（
second slave
）
1
SD+
5
SG
9
SD-
This product
（
31
st
slaves
）
Terminal
resistance120
Ω
Fig. 3-9 Connection of RS-485
【
Tips
】
Both ends of the communication connection (the end nodes) need to be
connected to the host computer.
The terminal resistance of this product can be set by the operation display
panel. Refer to “5.19 Communication function”.
Be sure to shut off the breaker of the facility power supply (the user’s
machine power supply) before wiring.
