When a motor is started by the controller shown in figure "C" of the illustration, what circuit components are in the holding current flow path through the control circuit while the motor is in operation? See illustration EL-0010.
• Trace the control circuit in Figure C from L1 to L2 with the motor already running and the Start button released. • Identify which contacts are normally closed (NC) (such as the stop and overload contacts) and which are auxiliary contacts operated by the M coil used for the holding circuit. • Distinguish between the Run path and the Jog path in the jog‑run push button selector, and note which contacts are used only while a button is depressed versus which stay closed after the coil energizes.
• Start at L1 and follow the path through the stop button and jog‑run selector: when the selector is in Run, which set of contacts carries current to the holding circuit? • Once the M coil is energized and the Start button is released, which contact must stay closed to keep current flowing to the M coil without needing to hold any push button in? • For each answer choice, ask: does this combination of contacts represent a path that remains closed continuously during normal run, or only while a button is held down (jogging)?
• Make sure the path you choose includes the stop button contacts and the overload (OL) contacts, since these must always be in series with the M coil in run. • Verify which specific labeled contacts in Figure C are the holding (seal‑in) contacts of the M coil (look at terminals 2 and 3 around the Start button). • Confirm that any contacts labeled "jog" are only involved when jogging and are not in the normal holding path for continuous run.
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