Instruction Manual

Configuration
Sealevel Systems SeaPORT+4/485 Page 5
Switch Descriptions
Figure 1: Switches SW2 and SW4
L 485 option, OFF for 422.
OFF: No effect
ON : Connects TX+ to RX+ for two-wire operation
L 485 option, OFF for 422.
OFF: No effect
ON : Connects TX- to RX- for two-wire operation
PU 485 option, OFF for 422.
OFF: No effect
ON : Adds a 1 K ohm pull-up resistor to RX+
PD 485 option, OFF for 422.
OFF: No effect
ON : Adds a 1 K ohm pull-down resistor to RX-
T 422 and 485 option.
OFF: No effect
ON : Adds a 120 ohm termination resistor between RX+ and RX-
ON
12345678
OFF
910
Port 3
L
L
T
PU
PD
Port 4
L
L
T
PU
PD
SW2
Port 1
L
L
T
PU
PD
ON
12345678
OFF
910
Port 2
L
L
T
PU
PD
SW4