Omega Four Port RS-232/422/485 to USB Adaptor, OMG-USB-SER-4 Electrical Interface Configuration

Configuration

Switch Examples Continued

Port 4 Port 3 Port 2 Port 1

RS 232 RS 422/485

Port 4

L

L

T

PU PD

SW2

OFF ON

1 2 3 4 5 6 7 8 9 10

RS 422/485 RS 232	RS 232 RS 422/485
Port 3
L
L
T
PU	Port 2
PD
	L
	L
	T
	PU
	PD

SW4

OFF	ON
1 2
3
4 5
6
7 8
9 10

RS 422/485 RS 232 Port 1

L L

T PU PD

E1	E2	E3	E4	E5	E6	E7	E8
		Figure 3: Electrical Interface Configuration
	Port 1 :	RS-232

The corresponding shunt is in the 232 position. The switches will have no effect.

Port 2 : RS-485 two wire communication with no echo.

The corresponding shunt is in the 422/485 position. Switches 485 2, NE 2, and Port 2 L, L, T, PU, and PD are all in the ON position.

Port 3 : RS-422 with 120 ohmtermination.

The corresponding shunt is in the 422/485 position. Switches 485 3,

NE 3, and Port 2 L, L, PU, and PD are all in the OFF position, T is in the ON position.

Port 4 : RS-485 two wire communication with echo.

The corresponding shunt is in the 422/485 position. Switches 485 4, and Port 2 L, L, T, PU, and PD are all in the ON position, NE 4 is in the OFF position.

OMG-USB-SER-4 Page 7