PLC coupling

Need to know what to use (relay,coupler?) to an output of 1 plc to the input of another Semiens S5. 1 in and 1 out. 700 cycles a min. what about a Crouzet 84 145 041?

That's too fast for a relay. At nearly 12 cycles per second it will be more like a buzzer...

Look at the specifications for the input and output points you intend to use; perhaps there is a safe way to directly connect them...

What do you mean by "1 in and 1 out"?

Paul

Sounds like a bad design, or trying to correct a mechanical problem with logic.

Plc coupling

we are adding sensors to a press and need a "slave" plc/smart relay to process those signals and then send a go/no go signal to the S5. I will probably use a transistor source plc or what ever to drive this "coupler" that will inturn send a pulse to an input to the S5. I haven't been able to find a Plc that will talk directly without electrical problems

Automation Direct has a new line of signal conditioners that will do the job for you. The DC model is relatively inexpensive. Or, you can build one with an opto-isolator IC (way cheaper) if you have the facilities for it.

Crouzet 84 145 041 has a relay output. No good for that application.
Crouzet 84 145 001 has a transistor output. OK if the S5 has 24VDC inputs.
Crouzet 84 145 021 has TRIAC output. OK if the S5 has 230VAC inputs.

PLC coupler

Thanks very much for the suggestions. I tried to get help from a couple suppliers. Customer service as usual in the USA, it sucks!!!

I'm still not sure what you are trying to accomplish.
In general, if you are talking the same signal levels (24VDC, 120VAC, etc) you can directly connect a PLC output to an Input.

The problem is if you are trying to do that at 700Hz from what I read. Are you using counter/encoder input modules?

The S5 is full and we want to add some error signals and to do this we need to add a plc to process some more go/no go signals and send that (1 out put) to an input to the S5. Everything is 24VDC. This will be done on a high speed Germany press ,700 spm. so can't use mechanical relays. the circuit is basically an and/or , if the sensors see a part, it will allow the press to cycle, no part ,the signal is to stop.The sensors are muted for about 350 degrees in the press cycle and looks for the part b/4 it starts another stroke ( 10 degrees).Hope this clears up guestions All the slave plc will do is precess each sensor data and send it to the S5 to determine go/no go for each cycle.

Why not just have an interlock from the add on module?

Normally Energized.

When the pass fail test fails, open a circuit to the high speed German press that will stop it...

Why the need for 12 pulses per second?

OkiePC---- the S5 has to process all the press dwell info. the press state ( position in cycle,etc.) is processed by the S5. So difficult to use your suggestion as would have to have 2 way communications.

In our business, we have an OEM from Germany that requires processing speeds similar to what you are requesting for fill volume calculations.
Our particular application uses a Siemens S5 Processor, communicating via PROFIBUS to a Siemens Proprietary high-speed i/o module, that have both Inputs and Outputs that suit your needs.

I cannot give specifics....but can point you in the correct direction if Profibus is an option.
It would save doing additional PLC work.

jerrys said:

we are adding sensors to a press and need a "slave" plc/smart relay to process those signals and then send a go/no go signal to the S5. I will probably use a transistor source plc or what ever to drive this "coupler" that will inturn send a pulse to an input to the S5. I haven't been able to find a Plc that will talk directly without electrical problems

Click to expand...

You haven't explained why there are "electrical problems" connecting the output of your slave PLC to an input on the S5. There shouldn't be, especially with 24vdc. It's done all the time.

If you have to match up two different kinds of I/O, then a solid state relay makes sense. Once again, easy to do for the 24vdc side. If you have to do 120vac, you need a load resistor to deal with leakage current, but it's still pretty easy.

From what I can tell, your cycle is as follows:

700 cycles per minute
each cycle is 1/700*60 = 0.0857 seconds per cycle

Not sure what "sensors are muted" means but I'll assume that the sensors are always "off" for 350 degrees and can only be active for 10 degrees of rotation.

0.0857/360*10 = 0.0277 second window

A small PLC can respond in this time frame, but can you tolerate the delay? How much time do you have to get the "go" signal at the start of this window?

I'm going to make a suggestion... Read the document referenced in Rdrast's signature. How to ask questions the SMART Way! I think you might find it beneficial, I know I did.

Good luck, and let us know how it works out.