The Force Reset commands are used to proof-test a Logic Solver. Forcing a reset causes the Logic Solver to de-energize its outputs, run power-up tests, and then resume running the application. Power-up tests reveal a small number of potential faults that periodic diagnostic tests cannot detect.
For redundant Logic Solvers, the Force Reset on Standby command is recommended over the Force Reset on Active command. Either command works as long as the standby Logic Solver is available. Both the active and standby Logic Solvers are actively reading inputs and writing outputs; however, the active is the primary Logic Solver for communicating with the controller.
Only the Force Reset on Active command is available for simplex Logic Solvers. Forcing a simplex Logic Solver through reset shuts down the process for outputs on that Logic Solver.
When it is time to proof-test a simplex Logic Solver, users will need to bypass or block final elements and briefly provide manual safety unless the proof test is done during a scheduled outage.
To force a Logic Solver reset