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Newbie Help Please - S7-400 DI & DO module ?s

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Hi folks.  This forum reminds me of the way folks who move to Texas talk about their new state... "I ain't from here, but I got here as soon as I could."  Look forward to being an active participant on both the giving and receiving side of the equation. 

I recently pieced together an S7-400 PLC for learning and testing purposes (I'm a security research type).  It's the fist PLC I"ve worked with, and while I probably didn't pick the easiest PLC to start with, I've made some good progress considering how little I know about it.  I've got a UR1 (18-slot) rack, a DC power supply (416) fed off an AC/DC converter I bought on ebay, the 443 CP module and then 2 Digital Input modules (421) and 2 Digital Output modules (422).

I've configured the hardware within Siemens Hardware Manager to reflect all the correct model numbers and downloaded the configuration to the PLC.  Nothing but green lights, and I have successfully been able to send a SZL request via ethernet with proper response.  So all appears well up to that point.

I've not yet configured anything regarding the individual input or output connections - perhaps that's why, but I don't see any lights - green, red or otherwise - on any of the DI or DO modules.  Is that my next step to get those working, or is this an indication that I may have a problem with them or the rack already?

Also, I was wondering if anyone knows of a good source with reasonable pricing for some simple input and output gadgets that I could use to play around with... like lights or buzzers or such on the output side and switches, buttons, etc on the input side... or if anyone knows of anyone who's documented working with an S7-400 to set up a basic lab (trials and tribulations, dumb mistakes, things you wouldn't know if this were your first PLC, etc)?

Greatly appreciate any time and thought you have to set me in the right direction.  I've had quite a bit of fun getting to this point, though admittedly it's not very far.

Thanks so much!

PR

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i have no access to siemens software any more (its been a while since i worked on it) but here it goes anyway:

1. your i/o need to be wired (at least must be powered)

2. if your i/o are not in the rack, with the CPU, you must setup network to access them

3. in the hardware configuration you must map all i/o points to addresses that CPU can address

4. when using low i/o count modules (ET200S for example) you can pack addresses tighter to avoid gaps56c89aa46e462_s7iomap.jpg.9a52de5f0f79d9

5. if using bus some planing is required. for example, this is how profibus is normally used. note details such as

         a. the green/red colors of wires and terminals (don't mix them!), shield must be connected on both ends to connector clamshell

         b. termination switch position 

         c. correct order of cable connections (A1/B1 port always goes to cable that leads to master, A2/B2 is either unused or goes to node away from master)

56c89d573ca97_ProfiBusconnections.jpg.17

 

56c89d742e821_profibuslayout.jpg.d8e9c82

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Hi Panic,

Thanks for the reply.  So is it to be expected that if I have the I/O modules installed in the rack (which has a powered UR-1 backplane), that I won't see any lights go on on those modules until I wire them to some input or output device with a 24vDC charge?

Thanks,

PR

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Have you taken the time to locate the Siemens manual for the I/O cards and look at the diagrams?

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