High speed motion detection?

I bought some PID motion detectors for arduino but they just fire once for 2 seconds then have another 2 seconds before they can fire again. This sort of behavior was not in the description and I would like to know if that is normal for PId motion detection.

I would like to buy a sensor that is HIGH when there is motion, and LOW when there is none. No delays or fixed time periods. The goal is to detect and count my cats when moving very quickly through a space. Any suggestions?

I think you wanted to write PIR(passive infrared) instead of PID. I don’t have much experience with PIR sensors i only bought a couple of HC-SR501 to play with them using arduino, and these also have a 3 second phase where they don’t detect motion and this cannot be overwritten, so I suspect this is a common thing.
But even if it would be possible to disable this delay, PIR sensors just detect motion, they can’t count the number of moving objects, so if your cats are moving together through the space you will get just one signal. Try to set up an infrared light gate somewhere in the room or at the door, an alternative to the light gate can be an infrared thermometer to detect body heat.