The Manual Mode Framework
The PLC Pro establishes Manual Mode whenever the control program is not in E-Stop Mode and not in Auto Mode. Manual Mode is derived from those mode conditions rather than separately latched or commanded. To implement this operating mode, the PLC Pro will:
Define When the Control Program Is in Manual Mode
The control program cancels Auto Mode when it enters E-Stop Mode. Manual Mode becomes active only after the control program detects that the safety system has been reset and exits E-Stop Mode.
Entry into Manual Mode does not authorize motion or resume an interrupted action.
Provide Deliberate Operator Control of Each Machine Element
Any machine action requires a deliberate operator command.
In Manual Mode, the operator may command an individual device, jog a mechanism, or initiate a limited sequence. The control program manages how each requested action is carried out.
In a PLC Pro installation, every actuator and every device capable of performing work is provided with the controls required to operate it in Manual Mode. The operator must be able to request the individual actions needed for setup, recovery, adjustment, maintenance support, and troubleshooting.
Apply Permissives, Interlocks, and Conflict Checks
Manual Mode does not bypass the installation’s safety systems or equipment protections.
A manual command requests an equipment action. The control program determines what outputs and supporting functions are required to carry out the request and evaluates the permissives, interlocks, and conflicts affecting them before executing the action.
Provide Current-State Feedback and Diagnostics
Under PLC Pro Methods, every actuator and every device capable of performing work has a Current-State indication representing the position or operating condition sensed by the control program.
The PLC Pro ensures that HMI diagnostics identify any detected condition preventing an action from being performed or completed. This information supports setup, recovery, and troubleshooting.
Establish the Control Foundation for Auto Mode
In the installation programming process, Manual Mode is developed and tested before Auto Mode. In developing and proving how each controlled machine element operates, the PLC Pro establishes the equipment-level commands, required supporting functions, permissives, interlocks, conflict checks, and Current-State feedback that automatic logic will later use.
Each machine element must operate correctly and predictably in Manual Mode before it is incorporated into an automatic sequence. Its commands must produce the intended action, its protections must prevent unacceptable actions, and its Current-State feedback must accurately represent the resulting equipment condition.
Developing these equipment-level controls also establishes the outputs and supporting functions required to perform each action and how their operation is conditioned in Manual Mode and Auto Mode. The control program accounts for E-Stop Mode, applicable permissives, interlocks, conflict checks, and other governing conditions when determining whether and how those outputs may operate.
Automatic logic will use the same proven equipment-level commands established in Manual Mode rather than duplicate the underlying output logic. Once those equipment-level controls have been verified, automatic sequences can be built on a tested and predictable control foundation.