23. Vibrating/Jog circuit -When, PB is pressed, output IR is activated. -But after several microsecond, the normally closed IR is open then will stop the output IR. -This applicable to move an object which need to locate at precise location.
26. Control circuit in ladder diagram. -When PB is pushed(forward/reverse),motor will move according to the command. -But, when there is an overcurrent,CB will stop the current flow by blow the fuse. -Means, NC of CB will open and stop the current flow to the circuit. -The circuit can be recovered by change the fuse. -If there is thermal overload, TOR will cut the current flow. -Lamp,L3 will turn on and TOR need to be reset.
27. Two wire control -only has one contact for switching device either ON or OFF state. -When ON state, M will energize and activate three phase motor. -Heater will heat if there is over current and open the circuit.
28. Three wire control -the connection almost the same as two wire circuit except has an extra set of contact connected in parallel as the pilot switch. -this extra contact provide extra third wire. -this auxiliary contact keep coil M energize even after start push button release.