Unipulse F331, Operation Manual

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32
7 OPTION
32
OP
TION
Chapter
7
■
RS-485 connection
Two-wire type (point to point)
- For connection, use twisted pair cables. (The noise margin will rise.)
However, a parallel two-core cable is good enough for short-distance connection.
- Install terminating resistance each on the
host side and F331 side.
On the F331 side, connect Rt. and B+ with
a short bar.
- The terminal SG is a grand terminal used
on the circuit for protecting the circuit.
When the main body of F331 and the
device connected to F331 are grounded by
D type ground, there is usually no need to
use the terminal SG.
However, confirm the specifications of the devise connected before connecting the terminal SG,
when it is necessary to connect it according to the situation of the site.
Two-wire type (multi point)
A-
B+
A
B
A
B
A-
B+
F331
PLC/programmable
display, etc.
Terminating
(Master) (Slave)
* Logic
- Mark state (OFF)
V
A
-V
B
<-0.2V
- Space state (ON)
V
A
-V
B
>0.2V
V
A
: Voltage of terminal A-
V
B
: Voltage of terminal B+
Terminating
resistance
* The F331 side terminating resistance (110 Ω )
can be short bar-installable/uninstallable.
resistance
( * )
Rt. B+
Terminating resistance
Short bar
(110 Ω ) self-contained
A-
On some master devices, A and B may be indicated reversely.
If communications are unsuccessful, interchange A and B.
Attention
A
B
A- B+ A- B+ A- B+ A- B+
Twisted pair cables
F331 F331 F331 F331
Terminating
Terminating
resistance (110 Ω )
can be
short bar-installable/
resistance
uninstallable.