AB PLC 5 question key switch modes

I have used different PLC's in the past but I am working on a project and editing a small project using an AB PLC5. This is an easy question but I am unfamiliar with PLC5. Could someone explain the Key switch modes: Program, Remote Run, and Run. When to use what mode and when to not and the rules on switching when an opertion is ongoing. I currently have a PLC5 running an operation and the Key switch is in Run and I want to do editing on several rungs but cannot due to it because it is in Run. Can I switch the Key from Run to Remote Run without disturbing the operation? I read not do switch to Program because it will disable the operation the PLC5 is controlling. Help me in this uncertain area on the do's and don'ts

Switching to remote run will not disturb the operation of the processor. It will give you the option to change the operating modes remorely via the programming terminal/software.

I'd leave it in remote so you don't have to worry about it next time. But I suppose thats up to the place you work. Big companys like to keep maintenance guys locked out to take away the extended break time option.

Thanks. I can switch from Run to Remote Run and back without disturbing the operation. I think I understand it now the Run mode disables programming and the Remote Run allows online programming. ScotttheEngineer added leave it in Remote Run if the Company allows. I think that is a good idea.

In my opinion they should have called the switch positions program, run and remote.

Program, is hard program mode
Run, is hard run mode.
Remotote is either, controlled by the programming terminal.

Most un-networked PLCs I have run into, are set to hard run via the keyswitch, whereas most networked PLCS I come accross are left in remote so you don't have to go to the control panel to chage the mode.

Marc