How many NI USB 232/4 modules can be connected to the PC?

[PaulBarr]

I have multiple sensors that communicate via RS232. I found a 4 port to USB.

Since I have more sensors. Can I connect a few more NI USB-232-4 to other USB ports?

[crossrulz]

They just show up as COM ports.  As long as they show up in the Windows Device Manager, I would say you were good to go.

[CFiset]

If I remember correctely, max 255 RS232 com port.

[CFiset]

http://stackoverflow.com/questions/16574040/how-to-determine-a-windows-systems-maximum-com-port-numb...

[nyc_(is_out_of_here)]

255 may be the theoretical limit but the practical limit will be less.

USB ports have a current limit.

[CFiset]

Yes, the USB port has a current limit, but if you use a usb powered hub, you can increased the number of device connect to the pc.

[Henrik_Volkers]

As far as I remember from my old days, you can hook up to 32 USB devices ..

And I had an application running with 4x 4RS232-USB ...   the biggest problem was a robust system for the field (No USB isn't a robust connection, a screwed secured RS232 is 😉 )and to reliable identify the sensor to port configuration after reconnect/ USB port swap .....  

[nyc_(is_out_of_here)]

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@Henrik_Volkers wrote:

As far as I remember from my old days, you can hook up to 32 USB devices ..

And I had an application running with 4x 4RS232-USB ...   the biggest problem was a robust system for the field (No USB isn't a robust connection, a screwed secured RS232 is 😉 )and to reliable identify the sensor to port configuration after reconnect/ USB port swap .....  

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Even when turnning off power saving on USB, I have seen instances where a USB connection will "disappear" in Windows.

A reboot of the PC would be required.

USB is to be avoided if possible.