Telenetics MIU Dial or Leased Line modem with RS-485 - Manual (Page 5)

Install Op and Diags for MIU Modems and RS485 (0049-0002-010A) Page 3 of 16
3.5 MIU/485 B switch (external)
SB-1 Closed (ON) RS485 Received RX & /RX DC terminated with SB-2 Closed
SB-1 Open (OFF) RS485 Received RX & /RX AC terminated with SB-2 Closed
SB- 2 Closed (ON) RS485 Received RX & /RX terminated
SB- 2 Open (OFF) RS485 Received RX & /RX high impedance (Z)
SB-3 & 4 Closed (ON) 2- wire configuration or loopback mode
SB-3 & 4 Open (OFF) 4- wire configuration