The Industrial Raspberry Pi Forum

Hi,

I'm having an issue with the MIO outputting only 20-22VDC, which isn't enough to trigger a relay. Shouldn't the output voltage be 24VDC?

Hi,
have you already made a measurement on the output you want to use? Check the Power Supply you use for your Device. Maybe it could be overloaded. As you can see in the datasheet of the device, the output voltage is 24VDC for MIO.



Best Regards

Ulrich Kouatang Biakoup | Technical Support

Thanks Ulrich. I've measured each DO and they are all outputting 20-22VDC when activated. The power supply is supplying a consistent 24VDC to both the RevPi and the MIO.

Hello,
How have you configured the outputs in Pictory, how many ohms does the connected device have?

Otherwise: Could you exactly draw of how you connected the relay. Are all voltages and corresponding masses used correctly?

Best Regards

Ulrich Kouatang Biakoup | Technical Support

Hi Ulrich,

I configured the outputs to be Digital Outs in pictory.

I swapped the MIO out with a DIO and it works, the digital outs are producing 24VDC. I'm unsure if the MIO is defective or if the tech had it wired incorrectly. Once I receive it back from the field I'll put it on the bench.

Ulrich,

I can confirm this behavior. I am using a Connect+ with the MIO module. When the X2 pin 1 is open-circuit and logic 1, I am measuring ~20VDC from the pin to ground. When connected to a stack light (24VDC typical operating voltage, 29mA max. current draw) the LED is barely visible. Measuring across the pin to ground I'm measuring 6.0VDC, and 15uA (yes, micro amps) in-circuit current.

On a different Connect+ with a DIO module and the same stacklight operating properly, I am seeing 24VDC across the pin to ground and 15mA in-circuit current (as expected).

In the MIO settings in PiCtory (2.0.6), "IO_Mode_1" is set to to "digitalOut". I am using "piTest -w DigitalOutput_1,1" to set the output value.

"piTest -d" for the MIO gives:

Address: 31 module type: 118 (0x76) RevPi MIO V1.0
Module is present
input offset: 0 length : 34
output offset: 34 length: 27

The MIO schematic is not available online so I am unable to research this problem further.

-Tim