barcode scanner splitter

This question is not exactly about PLC but somebody, probably, can help. We have an assembly line. At the final station there is barcode printer and barcode scanner, which are connected to the PLC. After assembled product have passed quality tests, barcode label is printed, applied to this product and scanned by barcode scanner. Signal from the barcode scanner tells PLC that part is good and off the line. Assembled product goes to the packing, where it placed on the skids. There is a PC with barcode application running, barcode printer and barcode scanner at the packing area. When parts are placed on the skid, they are scanned again. When skid become full new barcode label is generated and applied to the skid.
The packing place is very close to the final station on the assembly line, maybe 3-4 ft. I am trying to avoid double scanning at the assembly line and at the packing place. Is it possible to use some sort of Y splitter and connect one barcode scanner to both PLC on final assembly station and PC at the packing place? Currently both barcode scanners, which we are using, have RS232 interface. Does anybody know if Y splitter for RS232 interface exists? When barcode scanner connected to any recipient, is it any handshaking between devices? If such Y splitter exist, how would barcode scanner separate responses from PLC and PC?
Thanks in advance.
PaulB.

I'm no expert on this subject. It appears that both applications should be merged. In a general sense, the first part where you get the final assembly should be processed as you are currently doing. From there the info in the database should be used to derive the information for the second barcode.This could be routed to a second printer for the skid label when the skid is completed. It might be simpler to go the way you are now using the splitter arrangement on the scanner. There are many ways to set up a barcode scanner. I have used a Y type connection, (hard wired DB9 connectors), with only the RX(pin 2) and SIGNAL GROUND(pin 5) on the monitoring devices, (PLC and both PC's), tied to the TX(pin 3) and SIGNAL GROUND(pin 5) of the barcode scanner. All other pins were left unconnected other than a common shield to the shells.
What that amounts to is one way communication from the scanner to the other devices. I hope this helps.

Do you have PC there with PLC ? Are they connected together ?
Can you handle codes and printers by PC ?
If yes, do you need PLC anymore for that excluding 'Read-Code' trigger ?
One choice is more RS232C ports to PC. Readers and printers can
connect to PC ?

To clarify: PLC and PC are not connected together. They are completely separated and belong to different departments, so I would like to make as less changes as possible. It seems if I could use Y splitter, everybody would be happy.
Dear jrwb4gbm, could you please to make a sketch of your description and post it or e-mail it to me. Did you make such Y splitter in the house, or is it a product you can purchase? My email: [email protected]
Thanks,
PaulB

Does your barcode support RS485 communications? Sounds like you might be able to us a MUX (mulitplexor) <-sp?... You might have to re-write some code in your PLC to watch for some different characters coming in the channel if you MUX it.



RS485 def..

RS 485 is used for multipoint communications: more devices may be connected to a single signal cable - similar to e.g. ETHERNET networks, which use coaxial cable. Most RS 485 systems use Master/Slave architecture, where each slave unit has its unique address and responds only to packets addressed to this unit. These packets are generated by Master (e.g. PC), which periodically polls all connected slave units.

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