SMC Networks HRSH090 Series, Operation Manual

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HRX-OM-R026
Chapter 3 Transport and Setting Up
3.3 Installation HRSH Series
3-24
3.3.8 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

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.

Configuration of connection
One host computer : One thermo-chiller, or one host computer : N thermo-chillers.
(Max. 31 thermo-chillers can be connected.)
Fig. 3-16 Connection of RS-485
【
Tips
】
Both ends of the communication connection (the end nodes) need to be
connected to the host computer.
With or without the termination resistor (120
Ω) of this product can be set by
the operation display panel.
Refer to “5.21 Communication function”.
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
Be sure to lock out and tag out the breaker of the facility power supply
(customer power supply facility) before wiring.
Do not connect any wire to other PIN numbers.