Installation
20
J
RS-485
Q
Connecting to the RS-485 terminal (pH value input)
The converter is provided with a pH value input function by the HP-200 via the RS-485
communication.
z
The applicable electric wire is of 0.14 mm
2
to 2.5 mm
2
(AWG26 to AWG14).
z
For the communication output cable, use a twisted pair shielded cable.
z
The communication cable length is 500 m at maximum.
z
To terminate the cable, strip sheath by 11 mm from the tip of wire and connect it to the
terminal.
z
Connect a terminating resistor (Rt: 120
Ω
) to the terminal of the RS-485 communication
line.
z
One-on-one communication should take place between the converter (HR-200RT) and
HP-200.
z
Set the HP-200 address to “1”. For the address setting, refer to the instruction manual for
the industrial-use pH converter (HP-200).
Q
Connecting the RS-485 terminal
The converter has an RS-485 communication terminal. To use this terminal, connect wiring.
z
The applicable electric wire is of 0.14 mm
2
to 2.5 mm
2
(AWG26 to AWG14).
z
For the communication output cable, use a twisted pair shielded cable.
z
Up to 32 units can be connected including one host computer. For the address settings,
refer to “ RS-485 address setting ” (page 36).
z
The communication cable length is 500 m at maximum.
z
To terminate the cable, strip sheath by 11 mm from the tip of wire and connect it to the
terminal.
z
Connect a terminating resistor (Rt: 120
Ω
) to the terminal device of the RS-485
communication line.
Q
RS-485 communication conditions
The RS-485 communication conditions are shown below:
RS-485
(communication output)
(
+
)
(
−
)
pH-IN
(RS 485)
Example of external
connection for communication
RS-485
(communication output)
Converter
Rt
Rt
HP-200
RS-485
(communication output)
HR-200RT
RS-485
(communication output)
(
+
)
(
−
)
Terminal treatment for cable
11 mm
converter
Rt
Rt
Host computer
HR-200RT
Example of external connection for communication
RS-485
(communication output)
Item
Condition
Baud rate
19200 bps
Character length
8 bit
Parity
None
Stop bit
1 bit
