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Network Adapter

The Niobrara BB85 is a small DIN rail mounted breakout box intended to simplify connection between a Modicon® style RS-485 port with an RJ45 connector and a 2-wire or 4-wire RS-485 network.

The BB85 makes linking a CNOE, CNOS, CUCM, QUCM-O, QUCM-OE or a Momentum™ RS-485 Serial Option Adapter to a network of POWERLOGIC® devices easy; there is no need to install a modular plug. The RS-485 terminal block uses the pinout familiar to POWERLOGIC users (see diagram below).

A Niobrara MM0 RJ45 straight-through cable is supplied with the unit to connect the QUCM, CUCM, CNOE-800, CNOS-001 or other device to the BB85. The POWERLOGIC or other RS-485 network is then connected to screw terminals having the pinout familiar to POWERLOGIC users.

Niobrara can provide cables for other RS-485 pinouts and connectors to utilize the BB85; contact the factory for details.


  1. Confirm that the Modicon style RJ45 serial port to be connected is set to RS-485 mode.
  2. Use the supplied MM0 cable to connect the RS-485 port to the BB85.
  3. Connect the POWERLOGIC or other RS-485 device to the terminal block connector according to the pinout diagram below.
  4. For 2-wire operation: jumper the IN- to OUT- to form the (-) connection; jumper the IN+ to the OUT+ to form the (+) connection..
  5. Refer to instructions for the connected devices.


Below is a pinout diagram of the BB85 showing standard POWERLOGIC cabling on the terminal block:


BB85 is available as:
BB85 RS-485 Network Adapter with an MM0 cable..

BB85 Accessories:
NC5-T Replacement Green 5-position RS-485 connector.

Effective 19 March 2008 - Specifications subject to change without notice.