Industrial RS-232 to RS-485 Converter


The GM-1004E-B converts RS-232 signals into balanced differential RS-485 signals. The converter is designed to protect the RS-485 port; with integrated TVS’s (TRANSIENT VOLTAGE SUPPRESSOR).

  • Transmission media: twisted-pair or shielded cable
  • Baudrate: 300ps-115.2kbps

Product Documents

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Model #: GM-1004E-B Categories: ,

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For communication between PC with different standard serial port and external equipment or intelligent instruments, where standard serial conversion is necessary. The GM-1004E-B converter is compatible with RS-232C, RS-485 standards. It converts RS-232 signals into balanced differential RS-485 signals. This converter is designed to protect an RS-485 port; as it adopts advanced TVS’s (TRANSIENT VOLTAGE SUPPRESSOR). The transmission distance of RS-232 communication can be extended to 1.2km. It adopts unique “RS-232” charge boost technology to drive the system, and gains power without initializing the RS-232 serial port. This converter has built-in zero delay auto receiving, and transmitting conversion, offers unique I/O circuit with auto data flow direction without any handshake signal (RTU, DTR); this guarantees that there is no need to modify programming under RS-232, will run smoothly under current software and hardware. The transmission rate is 300-115.2kbps. It can be used between hosts, host and SCM, which building a point to point, point to multipoint long-distance communication networking. It is widely applied in industrial automation control systems, all-in-one cards, access control systems, parking systems, ATM systems, bus charging systems, canteen ticketing systems, attendance systems, and toll station systems, etc.



  • Standards: RS-232, RS-485 TIA/EIA
  • Connector: RS-232 DB9 female, RS-485 DB9 male, with terminal block
  • Operating mode: asynchronous half-duplex, differential transmission
  • Transmission media: twisted-pair or shielded cable
  • Baudrate: 300ps-115.2kbps
  • Operating temperature: -40℃ to 85℃
  • Relative humidity: 5% to 95%
  • Transmission distance: 1,200m (RS-485); 5m (RS-232)
  • Protection: RS-485 each line 600W surge, lightning protection

Additional information

Weight 0.07275 lbs
Dimensions 7.6585 × 5.7620 in






Item Dimensions

2.48 × 1.30 × 0.67 in.

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