MECH 4 Exam 3 QUESTIONS AND CORRECT
ANSWERS
T/F: A limit switch cannot be used as a safety interlock. - CORRECT ANSWERS False
The preset level where a pressure switch is activated is called the __________. - CORRECT
ANSWERS set point
not an automatic input device? - CORRECT ANSWERS Pushbutton switch
T/F: A normally closed float switch is needed for a sump pump circuit. - CORRECT
ANSWERS False
T/F: The upward or downward movement of the float device on a float switch controls the
switch. - CORRECT ANSWERS True
T/F: Automatic switches can have the same potential problems as manual switches. - CORRECT
ANSWERS True
T/F: Three-wire control circuits are commonly used for start/stop pushbutton stations. -
CORRECT ANSWERS True
When a relay is connected so that it continues to energize itself after a momentary input is
removed, the circuit is called a __________. - CORRECT ANSWERS Seal in circuit
T/F: Two-wire control circuits provide low-voltage protection. - CORRECT ANSWERS False
ANSWERS
T/F: A limit switch cannot be used as a safety interlock. - CORRECT ANSWERS False
The preset level where a pressure switch is activated is called the __________. - CORRECT
ANSWERS set point
not an automatic input device? - CORRECT ANSWERS Pushbutton switch
T/F: A normally closed float switch is needed for a sump pump circuit. - CORRECT
ANSWERS False
T/F: The upward or downward movement of the float device on a float switch controls the
switch. - CORRECT ANSWERS True
T/F: Automatic switches can have the same potential problems as manual switches. - CORRECT
ANSWERS True
T/F: Three-wire control circuits are commonly used for start/stop pushbutton stations. -
CORRECT ANSWERS True
When a relay is connected so that it continues to energize itself after a momentary input is
removed, the circuit is called a __________. - CORRECT ANSWERS Seal in circuit
T/F: Two-wire control circuits provide low-voltage protection. - CORRECT ANSWERS False
