IC1474A-F 703 p. 1 / 2 5853 Port Powered RS-232 to RS-422 Converter, DB9F to DB9F Product Code IC1474A-F This is a port-powered, two-channel RS-232 to RS-422 converter. It converts TD and RD RS-232 lines to balanced RS-422 signals. The unit is powered from the RS-232 handshake lines DTR and RTS. Only one of these lines must be present, and the unit will work regardless of whether the lines are high or low. Both the RS-422 driver and receiver are enabled at all times. To satisfy the requirements of some software, the RS-232 handshake lines are looped back (tied together). RTS is connected to CTS, and DTR is connected to DCD and DSR. Connections This converter is configured to transmit both directions between an RS-232 and RS-422 system. The RS-232 side is pinned out to connect directly into the COM port on your computer or any other DTE device (Table 1). The RS-422 side of the converter is pinned out as described in Table 2. When connecting to a RS-422 system, the converter must be connected with the proper polarity as shown in Figure 1. When no data is being sent the RS-232 line is negative and the RS-422 line TD(A) is negative with respect to TD(B). Table 1 - RS-232 Pin Out Signal DB9 Signal Pin # TD RD RTS CTS DTR DSR DCD GND 3 2 7 8 4 6 1 5 Table 2 - RS-422 Pin Out Signal DB9 Female Pin # TD A (-) TD B (+) RD A (-) RD B (+) GND 8 3 2 7 4, 6 Figure 1 - Connection to an RS-422 System Converter 422PP9R DB9 female 8 TD(A)3 TD(B)+ 2 RD(A)7 RD(B)+ 4 GND RS-422 RD(A)RD(B)+ TD(A)TD(B)+ GND Black Box Corporation - 1000 Park Drive - Lawrence, PA 15055-1018 Tech Support and Ordering: 724-746-5500 - Fax: 724-746-0746 To contact us about Black Box products or services: info@blackbox.com IC1474A-F 703 p. 2 / 2 5853 Biasing Resistors The biasing resistors for the RS-422/RS-485 receiver are 4.7k Ohm resistors. These resistors are labeled R1 and R2 (See Figure 2). Figure 2 RS-422 DB9 female RS-232 DB9 female RTS 7 Power Conversion Circuit CTS 8 DTR4 DSR6 +5V R1 4.7k DCD1 TD RD TD(B)+ 8 TD(A)- 7 RD(B)+ 2 RD(A)- 4 GND 2 R2 4.7k GND5 Specifications Communication: Data Rate: Power: Dimensions: Temperature Rating: 3 3 RS-422 115.2 kbps max. Port-Powered from handshake lines on the RS-232 side. 6.1 x 3.3 x 1.7 cm (2.4 x 1.3 x 0.66 in) 0 to 70C NOTE: When using an external supply, the supply should be connected only to specifically labeled power inputs (power jack, terminal block, etc.). Connecting an external power supply to the handshake lines may damage the unit. Contact technical support for more information on connecting an external power supply to the handshake lines. Model Number: Description: Type: IC1474A-F 9-Pin Port-Powered RS-422 Converter Light industrial ITE equipment Standards: EN 50082-1 (IEC 801-2, IEC 801-3, IEC 801-4) EN 50081-1 (EN 55022, IEC 1000-4-2) EN 61000 (-4-2, -4-3, -4-4, -4-5, -4-6, -4-8, -4-11) ENV 50204 EN 55024 Black Box Corporation - 1000 Park Drive - Lawrence, PA 15055-1018 Tech Support and Ordering: 724-746-5500 - Fax: 724-746-0746 To contact us about Black Box products or services: info@blackbox.com