Installation Of Option Board - Hitachi MICRO-EHV+ Applications Manual

Use the built-in termination resistors (120Ω) depending on the usage environment and the cable type. If the
communication is unstable, perform the followings.
(1) Instead of the built-in termination resistor, attach termination resistors that match the characteristic impedance
of the cable at both ends of the communication cable.
(2) Make wiring unconnected the SG (signal ground) of each device.
(3) Lower the transfer rate.
(4) Attach the ferrite core to the communication cable in a noisy environment.

2.20.6 Installation of option board

Remove the two covers (A and B) from the basic unit.
A B
(1) Plug the connector of option board to the connector of the basic unit.
C
A
(2) After connecting, attach the cover A.
A
B
A
For the prevention of the connector contact failure,
insert while holding the connector part of the option board.
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Chapter 2 Specifications