digital RS232 switch available?

I am using the serial port on a 5/03 to print labels to two different printers. Right now the user selects the printer they want to use by selecting the printer via a blackbox rs232 selector switch. I'd like to locate a selector switch which can be controlled via digital outputs from my PLC. I want to select the rs232 port by turning on a specific digital output. Does anyone know of an RS232 switch that can do this?

Black Box at one time made a software switch (I believe they called it a code operated switch) that would allow the PLC to send a couple characters to it that would switch between the various devices. I'm not sure if it is still available because the last I seen it used in a system was almost 10 years ago.

A search in google gave me this result:
http://dataprobe.com/redundancy_switch.html?source=googleAB&gclid=CPHDjKuq0pkCFQUVkgodEEwBvA

Archie said:

Black Box at one time made a software switch (I believe they called it a code operated switch) that would allow the PLC to send a couple characters to it that would switch between the various devices. I'm not sure if it is still available because the last I seen it used in a system was almost 10 years ago.

Click to expand...

They still have them.

http://www.blackbox.com/Store/Resul...-Sharing/Electronic-Switches/n-4294962090/p-0

Don't laugh, it works

We had a small assembly machine, where the operator loaded components, use a handheld barcode scanner to read in information, then the machine cycled assembling the component, and we needed to print a new bar-code label.

We scrambled at the 11th hour, and installed a DPDT relay to switch the two key serial lines from the bar code scanner to the bar code printer.

The PLC serial port was connected common terminals of the DPDT realy , the scanner via NC contacts, once the machine cycled, we energized the relay connecting the printer to the plc via the N.O. contacts.

We used an Allen-Bradley relay with GOLD plated contacts. This machine ran production every day with NO issue. (60 cycles per hour)

You only need to manipulate pins 2 and 3 (RXD TXD)

AB 700- HL T 1 2 Z24 X (The "X" gets you the gold plated contacts)

http://literature.rockwellautomation.com/idc/groups/literature/documents/pp/700-pp021_-en-p.pdf

What's wrong with a simple relay?
RS-232 is nothing fancy!

Th later posters are describing the relay method, which in essence a switch would be anyway. They are emphasizing the gold contacts for low noise switching. Standard contacts may generate momentary noise while switching which could be interpreted as serial information by either side of the switch.

bernie_carlton said:

Th later posters are describing the relay method, which in essence a switch would be anyway. They are emphasizing the gold contacts for low noise switching. Standard contacts may generate momentary noise while switching which could be interpreted as serial information by either side of the switch.

Click to expand...

That and eliminating contact oxidation. Standard contacts can oxidize and increase the resistance of the connection. Too much resistance and the serial signal can't get through.

Brian