🔍 Key Concepts
• Identify how a split-phase (resistive start, induction run) motor is shown in a schematic (look for separate start (S) and run (R) windings connected to common (C) without a capacitor).
• Distinguish current (amperage) relays from potential (voltage) relays and hot-wire relays by how they are connected in the circuit and what they monitor.
• Note what extra component appears in figure B compared with figure A, and where it is placed in relation to the run winding (R) and the line.
💭 Think About
• In figure B, what additional symbol has been added compared with figure A, and is it in series with the run winding, across the line, or in some other position?
• Does that added device sense current through the run winding or voltage across the start winding? How does its location tell you this?
• Looking only at the windings, do you see any capacitor symbol anywhere in series with the start winding? If not, what type of motor does that suggest?
✅ Before You Answer
• Verify whether there is a capacitor symbol anywhere in the start circuit; its absence or presence will immediately eliminate some choices.
• Check if the relay coil (the added device) is connected in series with the run winding or in parallel across the start winding; this is critical for identifying current vs. potential relay.
• Confirm that the labels S, C, R correspond to start, common, run terminals of a split-phase motor, and use that to trace the exact current path during starting.