Hitachi MICRO-EHV+ - 2.20 Option board

Chapter 2 Specifications
2 – 37
2.20 Option board
2.20.1 OBV-NES
Name and function of each part
Type
OBV-NES
Weight
15g (0.03 lb.)
(3) Basic unit connector
(bottom)
(1) Communication port
(2) Communication LED
(4) Terminating resistance switch
(bottom)
No.
Item
Description
(1)
Communication port
Communication port supports IEC programming function supporting Modbus-RTU master/slave
and general purpose communication.
*: IEC programming function is fixed to RS-485.
(2)
Communication LED
Flashes data transmission / reception.
(3)
Basic unit connector
This is a connector to basic unit.
(4)
Terminating resistance
switch
This is a switch to select to enable / disable the 120Ω built-in termination resistor.
ON: Enabled
OFF: Disabled
Terminal layout
Pin No.
Signal
Meaning
Internal circuit
[8]
[1]
....
Socket connector
(Top view)
[1]
N.C
Not used
Micro Processor
[4] SG
[5] SP
[6] SN
[7] N.C.
[8] N.C.
+
-
+
-
[1] N.C.
[3] N.C.
120
Terminating resistance switch
[2] N.C.
[2]
N.C
Not used
[3]
N.C
Not used
[4]
SG
Signal ground
[5]
SP
Send / Receive data +
[6]
SN
Send / Receive data -
[7]
N.C
Not used
[8]
N.C
Not used