I am not so sure what are you referring to when you say PIN. I think that you probably mean that when you use the web interface it ask you for a username and a password. The default configuration or this device is Username= admin, Password= no password is required. To get the device to its original default configuration you need to just press the Reset Button for five seconds or more. You can refer o the user manual of the device, specifically page 28
http://www.ni.com/pdf/manuals/372780c.pdf
