There are 3 types of password in using the M-series PLC:
1) Network access password - do you mean when you try "program transfer" and then it asked for the username/password? That username and password is defined in the TLServer for client to gain access to the PLC. There is a demo user called "samples" and has no password which is what we setup for you for a quick test. You can use that unless you have already changed the password. You can also add your own username and new password using the TLServer.
2) Program transfer protection password - This password is to protect against unauthorised attempt to change the PLC program or to upload the ladder logic from the PLC (available only in TL41.exe). The TL41.EXE "Erase password and clear program" command is used for clearing a program that has a password entered by previous user. Please note that this command erases the password and clear the program in the PLC completely.
3) Monitoring password: There is one more password type which is caused by execution of the "SETPASSWORD" in the TBASIC. If you have put this in the 1st. Scan pulse statement then it will not allow you to do any monitoring (and certainly not programming!) without a correct password. The only way you can circumvene this is to halt the PLC with DIP switch #4. This password is designed for use when the PLC is connected to a modem and anyone may be able to dial in (since in this case there is no TLServer to act as the guard). The dial-in user needs to supply a password before he/she can proceed further to take control of the PLC.
