🔍 Key Concepts

• Low voltage protection: what happens to the motor if supply voltage is lost and then comes back? • Low voltage release: what happens to the motor if supply voltage is lost and then comes back? • Difference between momentary (spring-return) and maintained (stays where you leave it) start switches in motor control circuits

💭 Think About

• When power fails while the motor is running, what do you want a protection circuit to do when power returns, in terms of automatically restarting or not? • When power fails while the motor is running, what does a release circuit allow you to do with just the switch position when power returns? • Which type of start switch (momentary vs maintained) makes sense if you want the contactor to drop out and STAY out after a power drop, until someone deliberately restarts the motor?

✅ Before You Answer

• Be clear on which design prevents automatic restart after a power failure for safety (think machinery suddenly starting). • Match momentary vs maintained switch types logically to how the motor should behave when voltage returns. • Ignore distractors about thermal-overload and normally open/closed line contacts – focus on how the circuit behaves after a voltage drop.