24 VAC Groov Input

Any plans for a Groov module that can handle a 24 VAC digital input? In G4 and PAC hardware, the IDC modules could handle low voltage inputs that are AC or DC. With Groov, that’s not the case. Any info on when I might be able to handle a low voltage AC input?

Bumping this up and hoping somebody has some information. This seems like a massive oversight in the Groov product lineup and is causing me all kinds of headaches as I convert projects from G4 and PAC hardware. I talked to tech support a few months ago and he seemed shocked that there’s not a Groov solution for this, but confirmed that there’s not.


If you don’t need fast response time or signal isolation, you may be able to use a GRV-IV-24 as a cost effective way to check those inputs with a little bit of control logic. Other analog modules would work as well that are faster, but the cost/channel gets steep for a digital input.

@philip: According to the documentation, that module only accepts VDC input. Am I missing something? Even the isolated module, the GRV-IVI-12, says it only accepts VDC input.

I looked into whether or not I could use an analog input module, even knowing the cost would be much higher, but I don’t think it’s a good option. I just don’t understand why the G4IDC5 and the SNAP-IDC5 modules were designed for both VAC/VDC and now the Groov module only handles VDC.

Yes, they are DC modules, so you would want to use the GetClearAnalogMaxValue command to see when the “DC voltage” is above a threshold - You can think of the 24VAC signal as a DC signal that is changing between approximately -34 and +34VDC. So if you see the max or min voltage change to those values, then you know the input is on.

Since the step change on that module is pretty slow, I would expect some seemingly random values when the signal is on - I would recommend testing that to see if it will work in your application - you may need to use a fairly low voltage for the threshold and turn off any signal averaging (SMA) since it would tend to average towards zero volts. The module also has some hardware input filtering that may work against you. A series diode may be needed if the filtering is too much to keep the voltage positive.

This is just an idea, and would need to be tested to see if it would work. I don’t have one of these modules or I would test it for you - maybe @Beno has the equipment available to throw together a quick test.

@philip: Thanks for the suggestion. I may be able to get that to work, and I have a GRV-IV24 module I could test with, but I’m just not sure it’s worth that much trouble.