GearMo GM-482422
USB TO RS-485/422 Interface Converter User Manual
Introduction
Compatible with the Recommended Standards of USB, RS-422 and RS-485, GM-482422 photoelectric isolation interface
converter can convert the single-ended USB signal into balance differenced RS-422 or RS-485 signal.
The
GM-482422
USB to RS-485 or 422 Converter’s built-in photoelectric isolator can
provide an isolation voltage of as high as 2500Vrms. It is also manufactured with a
rapid transient voltage suppression protector; this is protection for the RS-422 or RS-
485 interface developed with advanced TVS (Transient Voltage Suppressor)
technology adopted.
Under normal o p e r a t i n g conditions, the TVS tube is in the state of high
resistance. However, when both ends of the TVS tube are hit by a transient high
energy, the impedance at both ends can be suppressed by the TVS at a very high
speed. After absorbing a high current, the voltage between the two ends is
suppressed and kept at a pre-set value; therefore no damage is caused to the
electrical components behind by the transient high voltage impact.
The surge protection in the
USB to RS-485 converter
can effectively restrain lightning or ESD (electrostatic discharge)
with a protection voltage of 600W on each line for lightning surge, surge voltage, or transient over-voltage possibly
caused by other electrical sources. In this case, the USB to serial converter will maintain the high-speed transmission of
RS-422 or RS-485 interface ensured by the tiny capacitance between the poles.
RS-422 and RS-485 Interfaces
RS-422 and RS-485 interfaces with a DB9 male connector that is to be used
for connection. The internal zero delay auto transceiver contained in the
unique I/O circuit, controls the RS-422 converter’s data stream direction
automatically. No handshaking signal required (for example RTS, DTR etc).
The GM-482422 USB to serial converter is plug-and-play, no jumper settings
needed for mode shift between full duplex (RS-422) and half duplex (RS-
485). The converter is applicable for the existing communication
software/hardware interface.
A reliable and stable point-to-point and point-to-multipoint communication can be ensured by GM-482422 photoelectric
isolation interface converter. For point-to-multipoint communication, as many as 32 interface facilities of RS-422 or RS-
485 standard can be connected to each converter with a high 300-921.6KBPS data transmission rate. LED indicators for
Power and Data are also available with the converter for malfunction indication. Two conversion communication
modes including USB to RS-422 and USB to RS-485 are supported.
