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W&T
Subject to error and alteration
USB Interfaces
Interface USB <> RS232/RS422/RS485, #38211
The W&T USB-Interface Model 38211 enables bi-directional
connection of computers having a USB port with RS232 and
RS422 devices as well as with RS485 bus systems. In RS232
mode the device supports all signals present on the 9-pin
RS232 interface, in RS422 mode one data and one handshake
signal respectively, and in RS485 mode one data signal in each
direction. The converter is integrated in a plastic housing for
mounting on EN 50022-35 standard rails.
Supply voltage
The Interface requires no additional external power supply,
since it is powered through the USB. The current draw of the
device is max. 200mA.
To reduce the load of the supplying USB host or hub, the
Interface can however be powered by an external 5V power
supply. Suitable power supplies can be obtained from W&T
under article number 11053.
Galvanic isolation and ESD protection
The Interface has galvanic isolation with an isolation voltage of
1kV DC between the USB and the serial side. All signal lines for
the Interface are protected against static discharge for a
voltage of up to 15kV per IEC 801-2, Level 4..
