Question

Good Day to everyone,

I'm exploring the I/O features of the RUT955 router. I hooked up my 4-20 mA injector to pin 9 (+) and pin 6 (-). I also added a 1.2k resistor between them. The WebUI reads correctly the input current value in I/O Status section until it reaches 12 mA. In other words: good reading between 4 to 12 mA. But it cannot read above 12 mA, even if my injector outputs 18,19,20 mA and my multimeter confirms this current value...

Any idea what could be the problem?  

Firmware used: 7.01.4

Thank you!

Answer 1

Hello,

I have tested the device with the same firmware and several resistor values, but your issue did not replicate. The values do go above 12mA.

Your results would indicate a hardware failure. Maybe you have an opportunity to test another RUT955 with the same setup?

Best regards,

Žygimantas 

Comments

Hello,

I just received my second RUT955 unit and tried the same test, and I still have the same result (max 12 mA).
I'm not sure it is a hardware failure... Apparently, there's a software limitation to 13 mA (top). I put in series my multimeter and my reading is also limited to 12 mA. I guess if it was a failure, there would be no correct reading (?)...
As an FYI: both are brand new units bought at Mouser USA, this month.
Please advise.

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Hello,

Are you following the measuring setup provided in this page: https://wiki.teltonika-networks.com/view/RUT955_Current_Measurement_with_Analog_Input?