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Hjelmslund Electronics   Frederiksborgvej 135 - 2400 Copenhagen NV - Denmark        Phone : +45 5150 4986        Mail :

flag  Delivery to United Kingdom: 2 days. Cost: UKĀ£ 9.60
RS485 converter for industrial use

Our USB to RS485 converters

  Hjelmslund Electronics are specialized in making rs485, rs422 and rs232 converters, targeting customers who needs converters that have better quality than the cheap un-isolated, but smaller and less expensive than the industrial types of converters.
All our converters are isolated, powered from the usb side, and works with virtual comport drivers.
flag Dublin, IrelandJul. 2013
Very satisfied with the service and product supplied by Hjelmslund. Very fast response time, even when we required a special assembly. High quality product, worked excellently first time.

John Clarke - Nines Engineering
Website :

USB RS485 converter

2 wire half duplex rs485 converter: USB485-STIXL

USB485-STIXL : USB to RS485 converter with 2500 volt isolation

Connect your control network to the PC with an isolated RS485 converter, using it as a virtual com port.
Its isolation barrier and readiness for Modbus gives it the quality needed for use in industrial automation.
2 wire half duplex w. Automatic Rx/Tx switching and Rx/Tx FIFO for smooth operation - no programming of RTS to set the direction, and no dip-switches.

USB485-STISO   - as STIXL, but smaller terminals.

PDF Icon  USB485-STISO/STIXL product sheet

Shopping Buy USB485-STISO Online

Shopping Buy USB485-STIXL Online

USB isolator and repeater

USB isolator and protection device: USBISO-AA

USBISO-AA : Driverless USB isolator and protection for USB 2.0 full speed systems.
The USBISO-AA isolator is intended to be used in industrial environments where the host computer needs to be isolated and protected from external surges and electrical interference.

Brief specs.
- 1.000 Volt DC isolation
- IEC 61000-4-2 Level 4 ESD Protection
- USB 2.0 Full Speed
- Can deliver 200mA to the external USB device
- No drivers needed, can function on all systems

PDF Icon  USBISO-AA product sheet

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USB to RS422converter - isolated

4 wire full duplex rs485 / rs422 converter: USB485-STI4W

USB485-STI4W : Isolated USB RS485/422 converter

Our 4 wire full duplex model of USB to RS485 converters.
The receiver is always enabled, but the transmitter is only enabled during data transmission, thus making it possible to use it even as a slave device.
Drives up to 256 nodes, 1Mbps, 2.5kV isolation voltage.

* RS422 users : You can use the STI4W converter without any problems. The STI4W fullfill both RS422 and RS485 specifications.

PDF Icon  USB485-STI4W product sheet

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RS485 cable modbus

RS485 with cable and RJ45 - for Modbus: USB485-MB45

USB485-MB45 : Isolated RS485 converter with cable and RJ45 for Modbus
The RJ45 is wired according to the Modbus specifications Ver 1.02   Section 3.5.1

Pin 4 : Data -
Pin 5 : Data +
Pin 8 : Common

Extremely flexible shielded cable where the shield is connected to Modbus 'common' internally in the converter.
Standard cable length is 3 meter, but 1.5 / 5 / 10 meter versions will be available as well.

PDF Icon  USB485-MB45 product sheet

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USB virtual com port

Isolated RS485 panel mount converter: USB485-ILP

USB485-ILP : Panel mount RS485 converter

Low profile version of our GISO model.

Mount it as any other port in your enclosure, with the USB connection outside and the RS485 cable inside. By placing your isolation barrier in the cabinet side, you avoid getting USB cables into your industrial installation, as well as avoiding having industrial communication near your pc, hence maintaining the best possible system separation.

PDF Icon  USB485-ILP product sheet

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USB RS232 converter

Isolated RS232 converter: USB232-STISO

USB232-STISO : Isolated USB to RS232 converter

Our RS232 USB converter supports up to 1Mbps speed and includes 256 bytes Tx FIFO and 128 bytes Rx FIFO for smoother data transmission.
The USB side is electrically isolated from the RS232 interface, hence protecting the PC against electrical fails from your RS232 system.
The isolation protects for fails up to 2500Volt.

Compact - USB powered - Virtual comport drivers.

PDF Icon  USB232 product sheet

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Hjelmslund Electronics   Frederiksborgvej 135 - 2400 Copenhagen NV - Denmark        Phone : +45 5150 4986        Mail :
Updated 16. August 2015