🔍 Key Concepts

• Look closely at the text printed near the feeder disconnect contactor in the one‑line portion of the diagram (upper right). It describes how the contactor is closed and how it is held/tripped. • Compare an electrically latched contactor (coil must be energized and holding contacts maintain the circuit) versus a mechanically latched device (it stays shut by a mechanical latch after a brief electrical pulse). • Trace the control circuit for coil M and relay 1CR to see whether the main coil must stay energized for the contactor to remain closed, and what happens when control power is lost.

💭 Think About

• Ask yourself: after the contactor is closed, does the diagram show a continuous holding circuit that must stay energized, or does it look like a momentary close coil with some kind of latch? • If all 120‑V control power from the transformer were lost, what would this particular contactor do according to the diagram labeling—would it pop open, or would it stay in its last position? • Which option in the answers best matches the combination of being closed by an electrical signal but held in place (and released) in another way shown on the print?

✅ Before You Answer

• Verify the small label near the contactor that uses the words electronically, mechanically latched, and mechanically tripped—match those words to the choices. • Confirm whether there is a separate trip path (for example, through device R or another coil) that acts on a mechanical latch rather than simply de‑energizing the close coil. • Check that no normally open auxiliary contact is used as a holding contact in series with the close pushbutton that would be required for an electrically latched contactor.