🔍 Key Concepts

• Carefully trace the control (ladder) circuit at the bottom of EL-0170, not the power circuit at the top. • Identify which normally-closed contacts open whenever M6 is energized, and which normally-closed contacts must be closed for M6’s coil to energize. • Remember that an electrical interlock between contactors means their auxiliary contacts are wired so that energizing one prevents the other from picking up.

💭 Think About

• On the high‑speed rung, which contactor coil is at the far right, and which labeled contacts are in series with its coil? • For each of those series contacts, ask: when that other contactor energizes, does it open this path and prevent M6 from energizing (or vice versa)? • Compare the labels on those interlock contacts with the answer choices and eliminate any option that lists a contactor that does NOT appear as a series interlock with M6 in the ladder diagram.

✅ Before You Answer

• Verify exactly which rung contains the M6 coil and read the labels on the contacts in that rung. • Confirm which of those contacts are normally-closed interlocks (not the start/stop pushbuttons or holding contacts). • Make sure every contactor you choose for your answer actually appears as an electrical interlock with M6 on the ladder diagram—if a contactor label never appears on M6’s rung, it should NOT be in your final choice.