When a contactor is closed using a momentary contact pushbutton switch, a set of __ contacts may be added to the contactor to form an electrical holding circuit and eliminate the need for someone to hold the pushbutton continuously.
Select one:
a. normally closed
b. normally open
c. magnetic
d. initiating
The NEMA or industry standard symbol for a double-break, momentary-contact, single-circuit, normally open pushbutton switch is shown at __ in Figure 320.12.
Select one:
a. I
b. III
c. II
d. IV