power Interface 3-end isolated RS232/RS485/422 converters Manual

                                    FS-485GT is a RS232 to RS485 and RS422 isolated converters particularly suitable for industrial applications, there are two DC / DC isolated power modules and high-speed isolated in the product and realize isolation between the power and RS232, RS485/422, RS232 and RS485/422, use the 9 ~ 40 VDC wide voltage to supply power, regardless of voltage jitter’s impact of communication. Use the unique zero-delay automatic sending and receiving conversion technique and baud rate adaptive technique. Plug-and-play, suit for all software, and in the high resistance state when not sending data.  Support multi-point communication, which is different from other similar cheap products in market. There is a built-in anti-static anti-lightning circuit in the product. Uniquely with power and sending/receiving indicator lights, the shape is the industrial structure of standard rail installation.

                                    Because the power, RS232 and RS485/422 of FS-485GT are all isolated, regardless the working power of FS-485GT is taken from the RS232’s equipment or the RS485/422’s equipment, or external connected alone, it can guarantee the isolation between RS232 and RS485/422.

                              Technical details:

                              1, interface standard: TIA/EIA-RS232C、TIA/EIA-RS485/422,  RS232 only use TXD, RXD, GND three wire

                              2, output is the four-wire full-duplex RS422 interfaces and second-line half-duplex RS485 interfaces

                              3, 9 ~ 40 VDC external power supply, power consumption is <1 W

                              4, photoelectric isolated voltage: power to RS232 and RS485/422:1000VDC

                              RS232 to RS485/422: 1000VDC(up to 3000VDC,statement is needed when ordering)

                              5, transmission medium: ordinary twisted pair: sectional area is 0.5 mm2, distributed capacitance <60 pf / m, impedance is 120 Ohm

                              6, work methods: RS485 half-duplex transparent transmission or RS422 full-duplex transparent transmission.

                              7, the largest communication distance is 3km (4800 bps), 2km (9600 bps), 1.2km (115.2 Kbps)

                              8, 32 nodes can be linked to RS485/422 

                              9, baud rate is 0 ~ 230 Kbps Adaptive

                              10, interface protection:

                              RS485/422: ± 15KV anti-static protection, 600 W anti-lightning (anti-surge) protection and the prevention of 60 V sustained over-voltage’s restoration protection.

                              RS232 interface: ± 15KV anti-static protection

                              Power interface: Overcurrent protection

                              11, temperature: -20 ~ 70 ℃

                              12, installation: installation of 35 mm standard rail and the bolt hole

                              13, Dimensions: 85 × 55 × 25


                              Products’ shape and definition of terminal signals:


                              Signal definition of connection terminal 

                              RS485/422 terminal(left)

                              Power terminal(right)






                              RS485 signal is positive


                              Not be used


                              RS485 signal is negative


                              Not be used


                              RS422 signal sending positive


                              Not be used


                              RS422 signal sending negative


                              Not be used


                              RS422 signal receiving positive


                              Not be used


                              RS422 signal receiving negative


                              Not be used


                              RS485/422 signal ground


                              External connect the anode of power supply


                              Shield ground(chassis ground)


                              connect the cathode of power supply



                              Pin number




                              Not be used

                              Not be used



                              RS232 signal receive



                              RS232 signal send


                              Not be used

                              Not be used , short with 6 already



                              RS232 signal ground


                              Not be used

                              Not be used ,short with 4 already


                              Not be used

                              Not be used ,short with 8 already


                              Not be used

                              Not be used ,short with 7 already


                              Not be used

                              Not be used












                              link of FS-485GT and the RS232 interface of equipment:

                                    FS-485GT can connect any RS232 serial interface, the RS232 socket of this product is defined by standard DTE interface. cable can be used to connect standard DCE interface. A crossover cable is needed for the DTE interface such as computer, as shown below , and this cable is incidental with the product. For other RS232 mouth witch didn’t array as standard signals, users should link sending to receiving, receiving to sending.

                              The application of products:

                                    FS-485GT can be used for point-to-point communications and multi-point communications. Except for linking several other RS485/422 interfaces, it can also make as many as 32 RS232 interfaces compose of RS485 or RS422 communication network, its communication range is up to 3km(4800bps)、2km(9600bps),1.2km(115.2Kbps). The addresses of each nodes are determined by the internal procedures of the equipment. Please connect the shield to the "FG" terminal of products when using shielded twisted pair,.

                              1, second-line half-duplex RS485 communication network:

                                    Turn the RS485 and RS422 selection switch K1 of FS-485GT converters to "485", the terminal resistance setting switch K2 on FS-485GT of  network’s terminal and start to "R", the terminal resistance setting switch K2 on other FS-485GT of the network to "OFF".

                              2, 4-wire full-duplex RS422 communication network

                                    Turn the RS485 and RS422 selection switch K1 of FS-485GT converters to "422", the terminal resistance setting switch K2 on FS-485GT of  network’s terminal and start to "R", the terminal resistance setting switch K2 on other FS-485GT of the network to "OFF".


                              With RS232 Cable