4Tech Support: 1-800-260-1312 International: 00-1-952-941-7600 (24 hours)
SRS4Fxxxx-100
Installation -- Continued
Set the 6-Position Switch -- continued
Switch 2 - 130 ohm resistor on “transmit”
up = Disable.
down = Enable. (Switch 5 must also be set to “2-wire” (up).)
When enabled, switch 2 inserts a 130 ohm resistor on the wire pair:
• Transmit/Receive (-) (B) RS-485 2-wire, transmit (-) RS-422 and
• Transmit/Receive (+) (A) RS-485 2-wire, transmit (+) RS-422.
Switch 3 - 1K ohm “pull-down”
up = Disable.
down = Enable. (Switch 5 must also be set to “2-wire” (up).)
When enabled, switch 3 enables a 1K ohm pull-down on the wire:
• Transmit/Receive (-) (B) RS-485 2-wire, transmit (+) RS-422.
Switch 4 - 1K ohm “pull-up”
up = Disable.
down = Enable. (Switch 5 must also be set to “2-wire” (up).)
When enabled, switch 4 enables a 1K ohm pull-up on the wire:
• Transmit/Receive (+) (A) RS-485 2-wire, transmit (+) RS-422.
Switch 5 - 2-wire / 4-wire
up = 2-wire.
down = 4-wire.
Set switch 5 to 2-wire (up) to enable the wire pair:
• Transmit/Receive (-) (B) RS-485 2-wire, transmit (-) RS-422 and
• Transmit/Receive (+) (A) RS-485 2-wire, transmit (+) RS-422.
for RS-422 2-wire, half-duplex operation.
Set switch 5 to 4-wire (down) to enable the wire pair:
• Receive (-) (B) RS-485 4-wire, transmit (-) RS-422 and
• Receive (+) (A) RS-485 4-wire, transmit (+) RS-422.
for RS-422 4-wire, full-duplex operation.
Switch 6 - RS-485 / RS-422
up = RS-485.
down = RS-422.
Set switch 6 to RS-485 (up) to prevent echo in the 2-wire mode.
Set switch 6 to RS-422 (down) to allow “transmit only” for the wire pair:
• Transmit/Receive (-) (B) RS-485 2-wire, transmit (-) RS-422 and
• Transmit/Receive (+) (A) RS-485 2-wire, transmit (+) RS-422.
Installation -- Continued
Install the Copper Cable (DB-9 port)
Install the copper cable as instructed if the media
converter has a DB-9 copper port (SRS4F31xx-100
models).
Note: Shielded RS-485/422 cables are required for EMC
compliance.
1. Locate or build RS-485/422 cables with a female DB-
9 connector on one end and a DB-9 connector that
is compatible with the other device on the other end
of the cable.
2. Connect the female DB-9 connector at one end of
cable to the male DB-9 port on the SRS4F31xx-100 media converter.
3. Connect the DB-9 connector at the other end of the cable to the DB-9 port
on the other device.
Install the Copper Cable (6-position terminal block)
Install the copper cable as instructed if the media converter has a 6-position
terminal block (SRS4F32xx-100 models).
Note: Shielded RS-485/422 cables are required for EMC
compliance.
1. Locate or build RS-485/422 cables with the six
individual wires stripped at both ends.
2. Insert the individual wires at one end of cable into the
six terminal block ports on the SRS4F32xx-100
media converter.
3. Insert the individual wires at the other end of the
cable into the six terminal block ports on the other
device, matching the same color of cable with the
number of the port.
DB-9
1
2
3
4
5
6
