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Hi all,

While I am creating a program to scan data every 2 seconds and save data per 10 seconds, it does not allow me to make this program. I am using 2 multiplexers and wanna save different voltage sensors to save the illuminance. But I get the error scan interval too short to measure 1 Sec. Also, this picture shows another error that I got on my last try.

https://drive.google.com/file/d/1BfdYhIhztgAxU7jputV5IE8ngAylhuxn/view?usp=sharing

Thanks for your help.

ShortCut has safeguards in it to help you have a successful program.

Mechanical relays in multiplexers have a usable life. In the AM16/32B, relays are rated for 5 * 10^7 operations. With a 2 second scan, you would do 43200 operations per day on the relays. That would wear out the multiplexer in about 1157 days.

The immediate problem you are running into is that multiplexers take time to switch channels. The 20 milliseconds channel switch time is not much when you are only doing a few measurements. In 4x16 mode, it takes 320 milliseconds to switch through one multiplexer.The measurements themselves require additional time. With all the noise filtering on for the measurements, it can take longer than 2 seconds read all the sensors on your two multiplexers.

Now that you know what the root issue is, you can create the program with slower timing in ShortCut then modify in CRBasic. Don't change the multiplexer channel switching timing. You can adjust the parameters of the measurement instructions to sacrifice noise filtering for faster measurements.

Thanks Davis,

I am not an expert to work withCRBasic but I changed the scan time to 10s and it worked. I believe that in the past we did not encounter such a problem but with Short Cut even if I put the scan time for 5s and the saving time for 30s it still does not create the program while it was fine before. Now, when the two numbers are the same, scan time and save time, it works well.

The other issue is that when I want to send the built program to the data logger, this window error pops up, and not able to run the program.

https://drive.google.com/file/d/1BfdYhIhztgAxU7jputV5IE8ngAylhuxn/view?usp=sharing

Any idea what is causing this issue?

Thanks

Make sure the datalogger is using the current operating system version. If the problem continues, contact technical support and send them the .scw that ShortCut created.