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Hjelmslund Electronics   Tinghøjvej 15 - 2860 Søborg - Denmark        Phone : +45 5150 4986        Mail :

2 Jan 2023 : Good news - we are back in business again, currently building up a stock of the devices we haven't been able to deliver for such long time.
More details here.
RS485 converter for industrial use

About us

Hjelmslund Electronics is a little private owned company located in Copenhagen, Denmark.
We have been in business since 1990, specialized in making projects for industrial automation according to customers specifications, involving interfacing PC to external instruments over RS422 and RS485 networks, mainly to the Chemical and Physics industry and research labs.

Our present  - Time changes, and so do we. In 2012 we decided to expand, from only making custom projects, to launching our own products and sell them from our website. We dare to say that our USB to RS485 converters are among the best on the market, combining high quality isolation barrier while still keeping it small.

Our future  -  is dedicated to expand our product line with more intelligent types of converters, positioning in the gap between our simple converters and more advanced debuggers.
Oh yeah, and we have to make a more modern version of our website!

Hjelmslund Electronics
Tinghøjvej 15    -    2860 Søborg    -    Denmark
Phone : (+45)   5150 4986

Our google+ page

What our customers say.

flag Basel, Switzerland 
I was looking for a solution other than adding up an RS485 to RS232 and an RS232 to USB converter. Hjelmslund Electronics has a solution that does it all. I had some issues getting the converter work together with a humidity transmitter and Hjelmslund did not give up until it was solved. This is the kind of companies I like to work with.

Roland Schaffner - Bakrona AG
Website :
flag Künzelsau, Germany 
We use a special version of the converters in our development department. Best quality, service and delivery with fair prices. Very fast sales support and Services. Best recommendation.

Karl-Heinz Schultz - ZIEHL-ABEGG SE
Website :
flag Dresden, Germany 
Through the great support and uncomplicated customization of the converters, Hjelmslund is a business partner you dont want to miss. Thank you!

Daniel Knobloch - KLIPPEL GmbH
Website :
flag Lausanne, Switzerland 
We are using the USB485 converter to update our product's firmware via a special connector. The Hjelmslund device works well for us as it is both compact and easy to connect to our system.

Patrick Balmer - BlueBotics SA
Website :
flag Duisburg, Germany 
We use the converters in our measuring system. The converters work very good on all speeds. The service is always great. Can´t say anything about the support, because everything work well so I don´t need it so far :-)

Jens Neumann - Gassen Instruments GmbH
Website :
flag Schliengen, Germany 
Works fine without any installation problems, different devices on different USB ports will not cause a lot of new COM ports if not necessary. Good product from hardware development up to software implementation. Friendly and fast service.

Hubert Gerspacher - SWR engineering Messtechnik GmbH
Website :
flag Valladolid, Spain 
We are using the converter USB STISO to connect monitoring systems such as temperature and hummidity transducers and to configure some other devices, and we have had yet no problems with this device. Really happy with it. Perfect support, always with the right answer to different issues and in a really short time.

José Hervás - TECOPY, S.A.
Website :
flag Zele, Belgium 
I use USB485-STISO for read-out Registers of PowerLogic PM710 from Schneider-Electric. Very fast delivery (even new screwdriver delivered with to ensure direct usability; for the small connecting screws wire-connection). Very good service and support. Thanks

Piet Selhorst - PUBLILUX NV
Website :
flag Mannheim, Germany 
The most handy RS485 converter I've seen so far. No more bulky boxes dangling around when testing RS485 equipment. And almost faster than light delivery.

Christoph Baumann - Power Plus Communications AG
Website :
flag Cusago (MI), Italy 
We use both USB232-STISO and USB485-STISO converters. They work very well with WinXP and Win7, where a most of other commercial converters fail to work because of driver incompatibility. From the day we discovered Hjelmslund, when we need a serial interface, we don't think about a converter, but about a STISO.

Luigi Sforzini - Wide Range s.r.l.
Website :
flag Zaragoza, Spain 
We use the USB485-ILP isolator and it works fine in our products. Very compact and easy to place. Good service.

Victor Cardaba - Ebers Medical Technology SL
Website :
flag Älvkarleby, Sweden 
I'm very satisfied with your service, always quick deliveries and good customer service :) We use the converters mainly to control electric vehicle charging equipment via Raspberry PI.

Kristinn Sigmundsson - Vattenfall Research and Developement AB
Website :
flag Herning, Danmark 
Vi Bruger RS485 STIXL til fejlsøgning på større Modbus netværk, hvor der er flere leverandører som kobles op. Hurtig og enkelt opsætning = hurtig fejlsøgning. Godt produkt.

Henrik Bærentsen - Lund & Erichsen A/S
Website :
flag Oderzo, Italy 
I've found this very interesting USB to RS485 converter, isolated and compact at the same time. And, most important, it works with my application because it's widely configurable; I promptly received a good support. I will use and suggest it for communication between our software and hardware products.

Francesco Gobbi - LAE Electronic SPA
Website :
flag Kerpen, Germany 
We use the products in our Drives department. The conversation was excellent like the delivery time. Thank you very much.

Stefan Warzeschka - WEG Germany GmbH
Website :
flag Älmhult, Sweden 
We use RS485 interfaces for diagnostics in heating systems. We have had problems witch other suppliers products, probably the generic FT245 driver. The Hjelmlund interfaces have shown no problems at all and the support & delivery is excellent.

Göran Nilsson - Elektronikkonsult AB
Website :
flag Budapest, Hungary 
Well these isolators did a great help in our development process. The linear positioning transducers we used in heavy-noise industrial environment could not work properly due to the electric noise lead to the units via the USB cables involving both power and data wires. Your isolators solved the problem immediately!

Dr. Zoltan Peres - FCI Composite LTD
Website :
flag Musselburgh, United Kingdom 
Received 4 USBISO-AA isolators within a few days. Good build quality. Plugged them in and worked straight away. Will recommend to others for USB isolation requirements.

Bob Christie - Allegro Microsystems LLC
Website :
flag Dublin, Ireland 
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 :
flag Jyskä, Finland 
Have used USB485-STXL a long time. And will do in future too! Simply the best isolated converter.

Markku Pöyhönen - Itumic Oy
Website :
flag Hisings Backa, Sweden 
This stable and high performance RS485-converter should be in every technicians laptop case. We are very satisfied with the converters stability and performance and the whole company uses it in our daily work.

Erik Johansson - ppm Industrial AB
Website :
flag Västerås, Sweden 
We are using the isolated USB-RS-485 products for our time and safety critical applications. We are very satisfied with the ease of use, quality and the functionality of the products.

Tomas Lindqvist - Q-TAGG R&D
Website :
flag Laer, Germany 
We received the stick in time. Easy installation of drivers. Good support - was needed to solve a hardware issue on our side.

Markus John - Welotec GmbH
Website :
Hjelmslund Electronics   Tinghøjvej 15 - 2860 Søborg - Denmark        Phone : +45 5150 4986        Mail :
Updated 3. June 2023