RS-232 to RS-485 Converters - ULI-226 Series


ULI-226 series converts RS-232 to RS-485 signals and extends RS-232 signals up to 1.2 km. This series are port powered.

  • BB-485CON


    Model 485CON, RS-232 to RS-485 converter, converts unbalanced, full-duplex RS-232 signals to balanced, full-duplex or half-duplex RS-485 signals. RS-485 is an enhanced version of the RS-422 balanced line standard. It allows multiple drivers and receivers on a two-wire system. The RS-232 port uses a male DB-25P type of connector with pins 2 (TD input) and 3 (RD output) supported. Protective Ground (pin 1) and Signal Ground (pin 7) are also connected. The RS-485 port uses a female DB-25S type of connector with Send Data outputs on pins 2 and 14, and Receive Data inputs on pins 5 and 17. Protective Ground (pin 1) and Signal Ground (pin 7) are connected through to the RS-232 connector. The polarity of the two RS-485 lines must be correct. With no data being sent, the RS-232 line should be negative and the RS-485 "A" terminal should be negative with respect to the "B" terminal. If your equipment uses a " " and "-" naming scheme, in most cases the "A" line will be connected to the "-" and ...


  • BB-485COSR


    Model 485COSR, RS-232 to RS-485 converter, converts unbalanced, full-duplex RS-232 signals to balanced full-duplex (4-wire) or half-duplex (2-wire) RS-485 signals. The RS-232 port has a female DB25S connector with pins 2 (TD input) and 3 (RD output) supported. Protective Ground (pin 1) and Signal Ground (pin 7) are also passed through. Pins 4 (RTS) and 5 (CTS) are tied together. Pins 6 (DSR), 8 (CD), and 20 (DTR) are tied together, but not passed through the converter. The RS-485 port has a male DB25P connector with Send Data outputs on pins 2 and 14, and Receive Data inputs on pins 3 and 16, or 5 and 17. No special software requirements are needed since the RS-485 driver is enabled by the first transition on the RS-232 side of the Transmit Data line (Pin 2). Any transmission on the TD line keeps the RS-485 driver enabled by preventing the mono-stable multi-vibrator from timing out. The transmitter is disabled approximately 1 ms after the last transmitted character. This 1 ms timeo...


  • BB-485PTBR


    Model BB-485PTBR converts unbalanced RS-232 signals to balanced, full or half-duplex RS-485 signals. RS-485 is an enhanced version of the RS-422 Standard allowing multiple drivers and receivers on a two-wire system. The RS-232 port has a female DB9 connector with pins 2(RD), 3(TD), and 5(SG) supported. Pins 7(RTS) and 8(CTS) are tied together. Also pins 6(DSR), 1(CD), and 4(DTR) are tied together, but not passed through the converter. The RS-485 port has an 8-position pluggable terminal block connector. Model BB-485PTBR supports baud rates from 300 to 115.2K. 12VDC power supply required (not included, sold separately).


  • BB-485SD9R


    Port-powered, 2-channel converter changes RS232 TD and RD to RS485 for longer distance and multidrop function. Automatic Send Data Control enables driver when data is present on RS232 side. Powered from RS232 data and handshake lines (high or low).


  • BB-485SD9RJ


    The BB-485SD9RJ (ULI-226J) features Automatic Send Data Control, enabling the driver when data is present on the RS-232 side. The converter is powered from the RS-232 data and handshake lines, requiring no handshake line change to control the data lines.


  • BB-485SD9TB


    Port-powered, 2-channel converter changes RS232 TD and RD to RS485 for longer distance and multidrop function. Automatic Send Data Control enables driver when data is present on RS232 side. Powered from RS232 data and handshake lines (high or low). External power optional - PS sold separately.


  • BB-485TBLED


    Model BB-485TBLED converts unbalanced, full-duplex RS-232 signals to balanced, full or half-duplex RS-422 or RS-485 signals. RS-485 is an enhanced version of the RS-422 Standard allowing multiple drivers and receivers on a two-wire or four-wire system. The RS-232 port, configured as a DCE port, has a female DB25 connector with pins 2 (TD input), 3 (RD output), and 7 (Signal Ground) supported. Pins 4 (RTS) and 5 (CTS) are tied together, and pins 6 (DSR), 8 (CD), and 20 (DTR) are also tied together. Pins 1 (Frame Ground) and 7 (Signal Ground) are connected straight through to the RS-485 terminal blocks. The RS-485 terminal blocks support Transmit Data (A-) and (B ), Receive Data (A-) and (B ), Frame Ground, Signal Ground, and 12 VDC input. Model BB-485TBLED required a 12 VDC external power source (power supply not included, sold separately).


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