Hi,

I am new to PLC's. I have read many of the online PDF, websites, and found this site via Utube.

I want to setup a SLC 500 5/03 to do some logic for outputing to a device ( relay 1746-OW16 ) maybe?

What the input device will be is a Proface 577R panel LCD box. There will be 64 buttons assigned to on when pushed, off when released. One shot push is fine.

The output of this to the SLC 500 will become my matrix logic.

I have 8 inputs X0-X7, and 8 inputs Y0-Y7 ... any combination of these at reference closed switch creates an output to the respective pins on a motherboard.

X0 Y0

X1 Y1

X2 Y2

---

X7 Y7

X0 Y0 = Start

X0 Y1 = Coolant

X0 Y2 = Tool in



Like that... Now, my thought was 64 relays. Each relay creates a complete circuit and I get signal at the motherbroad. Then I thought, well I should only need 16 relays and get the logic worked out in the PLC for 64 inputs, and output to 16 relays that sets up the logic.

X0 Y1 X1 Y1 X2 Y1 X3 Y1

X0 Y2 X1 Y2 X2 Y2 X3 Y2

and on down the line using all combinations of X0-X7 Y0-Y7 ( 8 squared I believe ) 64

There is NO voltage or current involved with the complete of the circuit. It is just a reference to ground. Close the switch, get a complete circuit. The completed circuit sets up a 1 or 0 ( hi or low ) on the motherboard. Not referring to the logic inside the PLC.

So, do I use a relay setup and can I use 16, or do I need 64 ?

Can I only use outputs on module 1746-OBP16 ?

booleen math maybe?

Thanks for any direction you can give me.

Hi, sorry I didnt notice your post until today. I actually did a quick search and found your thread at plctalk and followed it through. My understanding is that you want to replace an old proface unit with the PLC. The proface works as a matrix type of input to your CNC machine control. I also see that you are planning on using 4 ow16's to try to perform this. Can you post a sketch of your wiring plans because I really dont see it. I cant see how you would duplicate the matrix since the relays share commons; however the fact that you plan on having 64 contacts at your disposal may mean that I am just not following you. Also, what are you planning to use to input your requests into the PLC? That is not clear to me either.

Russell

Hi,

Thanks for finding my postings. Yes, I am a newbie to PLC logic, but not wiring and electronics. I can program in basic and read VB also.

The HMI interface I plan to use is the Proface 577R.

The PLC is the SLC 500 5/03

The inputs to my machine are nothing but completing continiuty in a circuit with a relay.

I have the Proface programmed with the buttons now. I have my RSLogix 500 talking to the SLC500, but they are getting along at all. I am getting a invalid node address and I can not go online with the SLC500.

No matter if I can go online with it anyway, I do not have the ladder logic figured out. So many examples of running conveyer belts, and fluid flows on the internet, but not any simple logic on talking to modules inside the PLC. I guess they figure you should already have studied this.

Best I can tell, I have the switches made in the Proface and will output as an address to the PLC. Each one is B3:0/0 and so on. I have them set as momentary. I was thinking maybe a OSR on the ladder logic. I cannot figure out how to address the output to the relay module in the SLC500 however. I have seen alot of examples, but I dont know what I am looking for in figuring out the relay opening and closing.

I am very sure the relay setup of 8 common and then 1 indivdual output will make up the X0-X7 as common, and then Y0-Y7 making up the indivdual outputs. With 4 OW16's I will have 64 total possible combinations. I need 60 of those 64.

Can you give me a ladder logic example and I can figure it out for the whole 60 inputs. One guy tried on PLCnet but then Bernie said it was wrong and he deleted it.

Ok, yeah I guess I have been missing parts and pieces of what you are trying to do. Let me see if I understand correctly what you are trying to do.

-you mention not having a comm path with the SLC. All PLC projects are best taken in small bites. I would tackle this first. After all, nothing else will happen without it. If you are trying to connect throught the 9-pin rs232 port on the front of the SLC then no node is necessary. If you are trying to connect through the modular plug for RS485 then you will need a PIC module or compatible alternative. I would get this working first - then move on. If you are going to use an operator interface via the RS232 then you need to get the 485 comms working. The 232 comms are easier and may be a good exercise to get familiarl with rslinx and logix communications.

-I understand your OW contacts to be going to 60 different connections on your machine. Each contact closure will perform some type of function on your machine. You are basically using the contacts to short to ground. Keep in mind that your common should be run back to the machine common so there are no mixed current sources. I would wire one or two up as a test and make sure this works as my second task. you can force I/O in the SLC once you are online.

-I/O addressing in the SLC correlates with the slot number that the card is in. the processor takes up slot 0 and then each slot after that is 1,2,3,4 for each of your OW cards. Each slot will have a corresponding 16 bit output word. Each bit in that word correlates to one of your 16 contacts. Addressing for the bits starts at 0 and the SLC counts up in decimal to 15. Addressing is as follows: O:[slot]/[bit]

-the proface is your operator interface and it connects via a communication port (rs232 or 485?)

-It acts on bits within the PLC. Have you configured this? do you have the software necessary to configure this? As someone on PLCnet mentioned, I would look at some other operator interface. Cheap in hardware can be very expensive in time. I would recommend looking for a used RedLion O/I on Ebay. Easier to program and easier to use in the long run.

-Do some tests on your operator interface to understand what happens when a button is pressed and we can go on from there.

-You may want to sign up for our stage 3 for a month - should start up next week - that would allow us to talk in a webinar environment and allow you to look at the videos that cover much of this.