Hitachi EH-150 Series - Page 27

Chapter 4 Installation
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Table 4.8 RS-422/485 Signal (Port2)
Terminal layout
No.
Signal
Signal Name
Diagram of internal circuit
6
1
.
.
.
.
1
SD +
Send data +
Micro Processor
6) SG
1) SD+
2) SD–
3) RD+
4) RD–
5) TERM
+
–
+
–
110
2
SD –
Send data –
3
RD +
Receive data +
4
RD –
Receive data –
5
TERM
Built-in terminator
6
SG
Ground for signal
 Signal name and Connector pin arrangement (Port2)
Table 4.9 Signal name (EH-SIO side) and connector pin arrangement (Port2 / RS-422/485)
Pin
No.
Signal Name
Symbol
Signal Direction
Specifications
EH-SIO
External device
1
Send data +
SD +


Data send from EH-SIO.
2
Send data –
SD –


Data send from EH-SIO.
3
Receive data +
RD +


Data received from external device.
4
Receive data –
RD –


Data received from external device.
5
Built-in
terminator
TERM
( RD –)
--
When you use built-in terminator, please connect
with RD –.
6
Ground for signal
SG
--
--
Ground for signal
« Note »
A communication cable should use the twisted pair wire with a shield.