from the Testing MODBUS department...
MODBUS RTU help needed
Open interfaces, software and hardware topic
Posted by Chris Ferrell on 3 May, 2012 - 12:00 pm
Guys I need help. I'm a HVAC controls contractor and I have a constant issue with MODBUS RTU and my ability to connect to an MODBUS capable device. I want to be able to walk up to a device, (IE Rooftop HVAC unit, Data Center UPS unit) and connect to it with my laptop and see basic things.....It it addressed it communicating at all....can I poll a register...Can anyone help with this?

Posted by bob peterson on 3 May, 2012 - 12:51 pm
there are a whole bunch of Modbus master software packages out there.


Posted by David on 3 May, 2012 - 7:08 pm
Win-tech Modscan32 (run 5 minutes for free)

Simply Modbus

Chipkin Modbus Scanner

take out any spaces the forum inserts into the URL

Posted by Andrzej on 7 May, 2012 - 6:17 am

You can use the Modbus Tester as the master.

If you want to find the communication setup (slave address, Baud Rate, Registers range, etc.) you can use the Modbus Scanner.
The programs you can download from


Posted by Chris Ferrell on 7 May, 2012 - 11:59 am
Thank you guys!

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