Are the 4-channel SNAP digital input cards interchangeable?

Good morning,
We’ve been using the standard SNAP-IDC5 input card to “count” pulse signals from a water flow paddlewheel sensor to calculate the flow (at fairly high speed, e.g. 93 pulses = 1 Liter). I just noticed there is a similar SNAP-IDC5-FAST-A card that seems might be more suited for the application. Without changing our PAC strategy (would require version update), would the strategy still correctly detect and calculate the water flow? (I’m hoping our same software version would still work for customers that might have either one of the cards, the strategy still configured to use the standard IDC5 card).

We’ve had no major issues with the IDC5 card from the many systems out there, with the exception of one recently. This one isolated problem the customer has had to change the wiring from Channel#1 to Channel#2 about 6 months ago, and again last weekend – now he’s using his last Channel#4 input (no more lives left). Was wondering if it makes sense to replace the card with a “Fast” version of the card.

In summary, 2 questions:

  1. Can the 2 cards be used interchangeably (using only one strategy)
  2. If above is true, is it recommended to use the “FAST” card for this application?

Thanks for any info/advice on this…

From a strategy point of view I believe they are the same.
The key is here.
The IDC5 turn on/off times:

The IDC5-FAST-A turn on/off times:

The modules plug into the same rack and look the same to the controller.
Of course I would want to test that in a controlled setup as I cant speak for how your charts are accessing the I/O, delays, features etc.

Have they figured out why this is happening?

Wow, “Fast” is an understatement… Awesome, thank you!
Just wanted to make sure the strategy Opto script syntax was still the same, using the GetClearCounter(diSensor) command:
nFlowPulseCount = GetClearCounter(WaterSensor);
fFlowRate = (((nFlowPulseCount / uiOptions[cOptKFactorIndex]) / utFlowCheck) * 60);

So assuming a 50% duty cycle, I should expect the maximum pulse rate with the standard IDC5 to be 1000 msec / 30 msec = 33.33 pulses/second (compared to the “fast” 20,000 pulses/second!).

Philip, no we have not figured out root cause yet. Customer is not local and we have only been in contact remotely with their local electrician. It is a good question though, as we have these systems all over and I have not seen a similar issue before. I was planning on replacing it with a “Fast” card, and have the damaged card sent to Opto22 for assessment and/or warranty replacement if it qualifies… not sure if the assessment could determine root cause? Possible external wiring issue of sensor and/or card input?