Need some AD-06 ladder logic for figuring the RPM based on a proximity sensor signal?

The example for the DL105 should work for the DL06 with minimal changes.

There are two ways to calculate RPM from a pulse train.

1. You can count the number of pulses over a predetermined time. That gives you pulses per time unit. Multiply that by time units per minute and divide the result by pulses per revolution to get RPM. A longer time unit gives you better accuracy at the cost of less frequent updates.

2. Measure the time between successive pulse (or the time to accumulate a fixed number of pulses). That gives time per pulse which is the reciprocal of the value you got in method 1. Divide the time per pulse into 1 and do the same arithmetic as in method 1 to get RPM.

Be sure to make the target that the proximity switch senses big enough so the signal is on long enough to be detected by the PLC's input scan. 600 RPM is 10 RPS which is 100 milliseconds per revolution. That ought to be plenty of time to do it without the need for a high speed counter.

This may not apply to what Piscis needs but it's something to consider...

Just to note; If your calculating RPM for realtime motion control feedback, a prox switch counting from the shaft key (or something like that), might not provide satisfactory results.

600 rpm / 60 sec = 10 pps. at full speed. Ok for a readout display, but not very much to work with for real time control.....

The DL06 X0 & X1 HS counter can handle 7khz. Using a 360 ppr encoder x 600 rpm = 3600 pps. Using SP5 (100ms,)or SP6 (50ms) as your clock, you'd get a more reliable/accurate result, expecally at lower speeds.

In short, one second is a looongg time. For exampe a conveyer running at 100 fpm = 1.6 fps. If your using a 1 second clock, that's a lot of latency.

"Example of how to calculate RPM for a device connected to the High Speed Counter inputs on the 105 CPU"

I don't have a CTRIO or a any other counter, just a prox. Can anyone please provide some sample logic here? I'm curios to know and learn this ladder!!

What model DL06 do you have? If you have DC inputs, X0 & X1 are high speed counter inputs. Refer to Chaper 3 in the DL06 manual.

The code you downloaded, (or should have), can be used with a few minor alterations for the DL06.

I have the:

D0-06DR DL06 20 DC IN / 16 RELAY MICRO PLC W/AC P/S

The DL06-DR counter inputs are X0 & X1. When you setup the counter (CT174) in your program you wont notice the X-inputs, because they are read from the setup. You need to review Chapter 3 & decide which mode suits your application best. I cant tell you exactly what to do, due to lack of info...

First time I use the 06!! Did not know about these two high speed inputs!!!

Thanks for the info!!!