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Tigamaroo1999

Encoder with Compobus/S

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Hi all. I am trying to hook up two (2) four-wire encoders to a remote terminal block and realized that I have no idea how to do that. I know that for the CJ1M-CPU22 that I am using, the high speed counter(s) have to go on specific I/O points in order to use them, but I'm not sure what to do for these. There doesn't seem to be any information in the CompoBus/S manual, so I'm a little stuck. If I can't use the 4 wires (I think they're Hi, Lo, Rising, Falling), I would be able to use just two wires as I don't need the resolution that's provided. The encoder pulses 26.6 times per 1 mm of travel, and the travel rate is 8mm/sec. That means that I am receiving 212.8 pulses per second. Thank you for all your help (in advance of course)!!! Tom

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Based on the lack of response, can I safely assume that there isn't a way to do this?

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That's roughly one pulse per 5ms. Using a 50% duty cycle for pulse width, that's 2.5ms pulse width. Pretty fast for a regular PLC input. You do the math.

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Ok, so if I slow down my pulse train to 20ms per pulse, and using a 50% duty cycle, that puts me at 10ms per pulse....no problem, I can do that. The second part of this is, what command do I use? I think that I may be able to use a Reversible Counter (CNTR), but am not quite sure. Thanks, Jay, for responding. I realize some questions may be really basic (or even stupid) in your opinion. Please consider that I don't have a lot of experience in programming PLC's. Thanks! Tig

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What encoder model? Who makes it? If it is a line-driver or differential output, this won't work. Give me some specs or a link.

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Jay, The encoder is built into a Nook Industries linear screw-jack. The encoder circuit board has the name "ITALSEA", and a model "E2CS.2". From the Nook Industries manual (which I finally got in the mail just about 10 minutes ago), I see that the four wires for the encoder are as follows: Channel A, Channel B, Encoder -, Encoder + 5-25VDC. Also, the manual states that it is a "Quadrature output" and in an "Open collector configuration." The website for the screw jack (M20 Minilift Actuator) is: www.nookindustries.com I hope some of this helps you, as it seems greek to me. Thanks again! Tig P.S. I did a google search with little help. Also, I called Nook to ask them about it. Apparently, their tech help only deals with the mechanical part of their product.

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I would guess that the 'Encoder -' and 'Encoder +' wires are for its power supply - 5 to 24VDC. Quadrature output means that the signals from Channel A and B are separated by 90 degrees of phase shift with A leading B or B leading A depending on the direction of rotation. An Open Collector output is an NPN transistor that does not have its collector pin tied to any voltage source. This means that a source is required for the output to work. In other words, connect a +ve supply to an input card common, and the encoder channel to an input. This will allow the encoder output to sink current through the input to activate it. I will have to defer to Jay when it comes to relating this info to Compobus as I have no experience with this. Hope some of this helps! Andy.

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OK...Now before everybody jumps down my throat because you recognize this as a quadrature encoder....I've got an ace up my sleeve. First here's your wiring: Second, I've got to go hunt up some code.

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OK..If it was a snake, it woulda' bit me...found it in the Omron Download section...I put it there two years ago...I converted it from CPM1A to CJ1M. You will need to substitute your Compobus/S slave input addresses for the addresses for Phase A and Phase B in the enclosed code. Quadrature_Input_CJ1M.zip

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How do I open an .opt file? I tried using CX Programmer, but it wouldn't open. Am I just having a day (or week, year, or lifetime)? Thanks again! Tig

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Try again. I zipped the wrong file.

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Hey i have been lurking around here for a while now..... But here are two more ways do do this counting with an encoder/prox switches. One way is with a function block! ~Andrew Quadrature_Input_CJ1M_V2.zip

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Unfortunately, unless you have CX Programmer V5.0, you are not going to be able to open this file. For those of you who would like to see an example of what Andrew's function block looks like:

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ok, lets try a cxt file ~Andrew Quadrature_Input_CJ1M_V2.cxt

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Hi all! I just wanted to thank you both for providing such useful information! I am up and running and can consider this part of my programming complete! Thanks again! Tig

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