B&B Electronics 485OP - Quick Start Guide User Manual
Product overview, Wire the 485op, Set the jumpers

2
Label
Side
Signal
A(-) Data In
Left
TDA(-) / Data A(-)
B(+) Data In
Left
TDB(+) / Data B(+)
A(-) Data Out
Left
RDA(-) / Data A(-)
B(+) Data Out
Left
RDB(+) / Data B(+)
Signal GND 1
Left
Signal Ground
Prot. GND 1
Left
Protected Ground
GND
Left
Power Ground
A(-) Data Out
Right
RDA(-) / Data A(-)
B(+) Data Out
Right
RDB(+) / Data B(+)
A(-) Data In
Right
RDA(-) / Data A(-)
B(+) Data In
Right
RDB(+) / Data B(+)
Signal GND 2
Right
Signal Ground
Prot. GND 2
Right
Protected Ground
Product Overview
Wire the 485OP
3
Set the Jumpers
Set the Jumpers for 2 or 4-wire and for baud rate. Default
on both sides is 2-Wire, 9600. If you want to set the unit
for 4-Wire or change the baud rate, you will need a screw-
driver. Remove the 4 screws and open the unit. Set jumpers
as shown below.
1
Loopback Test
Data
LED
Connections
Data
LED
10 to 14 VDC
500 mA, 1 W
Baud
Rate
Time
(ms)
R26 & R27
(KΩ)
C15 & C16
(mfd)
JP2 & Jp4
300
33.3
330
0.1
E*1
600
16.6
160
0.1
E*1
1200
8.33
820
STD (0.01)
E*1
2400
4.16
STD (430)
STD (0.01)
A
4800
2.08
STD (200)
STD (0.01)
B
9600
1.04
STD (100)
STD (0.01)
C
19.2 K
0.52
STD (56)
STD (0.01)
D
38.4 K
0.26
STD (27)
STD (0.01)
E
57.6 K
0.17
39
STD (0.01)
E*2
115.2 K
0.087
11
STD (0.01)
E*2
230.4 K
0.044
4.7
STD (0.01)
E*2
460.8 K
0.022
2.2
STD (0.01)
E*2
RS-485 2-Wire
RS-422/485 4-Wire
RS-485 Master 4-Wire
If you set the unit for 38.4 it will usually work at higher
baud rates. If you need a specific turnaround time go to:
http://www.bb-elec.com/Products/Serial-Connectivity/
Isolators-Repeaters/Optically-Isolated-Repeaters.aspx and
go to the tech notes.
3
Power the Unit
You can perform a loopback test by connecting the 485OP
to an RS-422 to an RS-422/485 converter, or by connect-
ing it to a USB to RS-422/485 converter.
Set the 485OP for Full duplex on both sides with the
jumpers (See step 2). Attach the 232 to 422/485 or USB
converter to 1 side of the 485OP. Jump Data In A to Data
Out A and Data in B to Data Out B on the other side
Using HyperTerminal or similar program, connect to the
appropriate COM port. Turn off Hyper Terminal local echo.
Set baud rate to 9600. Transmit data. If you can see the
data you are typing the test is successful.
DATA OUT A
DATA OUT B
DATA IN A
DATA IN B
SIGNAL GND
PROT. GND