WorksheetsNCCER Electrical 3 Module 11
Total questions: 32
Worksheet time: 16mins
Which of the following are primarily designed for use with inductive motor loads and to
withstand the interrupt current of a locked rotor?
NEMA-rated contactors/motor starters
Definite-purpose contactors/motor starters
Lighting contactors
IEC-rated contactors/motor starters
A relay designated as a 3PDT-SB relay _____.
has three N.O. (normally open) contacts
has three N.O. (normally open) and three N.C. (normally closed) contacts
is a single-throw type
is a double-break type
The component marked 1 in the figure provided is a(n) _____.
melting-alloy heater assembly
overload contact
load terminal
reset terminal
The components marked 2 in the figure provided are _____.
overload contacts
reset terminals
melting-alloy heater assemblies
load terminals
A NEMA-rated motor starter consists of an enclosure containing _____.
one or more magnetic contactors with associated overload relays
a magnetic contactor and stop and start pushbuttons
a disconnect switch and magnetic contactor
a circuit breaker and magnetic contactor
If the heater in a fixed IEC bimetallic overload relay fails, _____.
the heater must be replaced with a heater of the same size
the entire overload relay must be replaced
it and all the other heaters in the overload relay must be replaced
the heater can be replaced with a heater of the same size or one that is slightly smaller
Inching is also referred to as _____.
throttling
jogging
stepping
plugging
The nameplate on a motor indicates that the motor has an FLC of 10A and a service factor
(SF) of 1.15. How much additional current can this motor safely handle for intermittent
power demands?
1.5A
1.75A
2.25A
3.5A
Most transient suppression modules consist of an RC circuit that is designed to suppress coil
voltage transients to approximately what percentage of the peak coil supply voltage?
75%
100%
150%
200%
If a duty cycle includes only noninductive or slightly inductive loads, select an _____.
AC-1 rated motor control device
AC-2 rated motor control device
AC-3 rated motor control device
AC-4 rated motor control device
A 240V-to-24V transformer is MOST likely to serve a _____.
motor control circuit
line-voltage lighting circuit
motor power circuit
machine tool
Symbol F in the figure provided represents a _____.
float switch
temperature switch
pressure switch
foot switch
A retroreflective scan is the scanning method in which _____.
the light beam transmitted from the transmitter is reflected back to the receiver by the
target to be detected
the target to be detected passes between the transmitter and receiver, interrupting the light
the target is detected as it passes between a photoelectric sensor and a reflector
the receiver responds only to depolarized light reflected from a corner cube reflector or
polarized sensitive tape
Symbol B in the figure provided represents a _____.
float switch
temperature switch
pressure switch
foot switch
A general-purpose NEMA enclosure is Type _____..
1
3
4
12
In the figure provided, the belt runoff switch ZS108A is connected to junction box JB108 by
cable _____.
C108G
C108H
C108J
C108K
The relay logic and truth table shown in the figure provided represents a(n) _____.
NAND function
OR function
NOR function
AND function
On a ladder diagram, pilot devices are located in the _____.
termination section
decision section
signal section
action section
A NEC Article 430, Part IX covers _____.
hazardous locations
overload protection
motor disconnects
enclosures
In the figure provided, the purpose of the M1 normally closed contacts shown in the control
circuit is to _____.
prevent the drain pump from operating when the fill pump is operating
provide memory for the Start switch
prevent the fill pump from operating when the drain pump is operating
provide memory for the float switch
The abbreviation DB stands for a _____.
dual-break relay
double-break relay
delayed-broadcast relay
dual-benefit relay
Equipment marked as UL Recognized has been
examined by Underwriters Laboratories, Inc. and
determined to be _____.
the same as equipment marked UL Listed
suitable for general use
acceptable for incorporation into another
product that can be UL Listed
the same as equipment marked UL Classified
Most IEC motor starters use _____.
melting alloy thermal overload relays with
interchangeable heaters
overload relays with fixed heaters
thermistor overload relays with interchangeable
heaters
electronic overload relays with fixed heaters
The motor starter that must be used with a 460V,
poly-phase, 60Hz, 90hp motor NOT used for
plugging or jogging applications is the _____.
NEMA Size 2
NEMA Size 3
NEMA Size 4
NEMA Size 5
The IEC lighting control used to switch a
transformer load is a category _____.
AC-1
AC-5a
AC-6a
AC-11
Electrical noise from a motor starter that may
interfere with nearby electronic circuits can be
reduced using a(n) _____.
adder kit
transient suppression module
status feedback module
electrical interlock
When selecting a control transformer for a specific
application, you have calculated its application inrush
to be 3,500VA. If the primary input voltage is steady
and not expected to vary more than 5% from nominal,
the transformer VA rating should be _____.
150VA
250VA
300VA
350VA
The contacts of a switch are rated as A300. In a
240VAC application, the maximum break current for
these contacts is _____.
1A
1.5A
3A
6A
The IEC code for an enclosure that is dust-tight and
provides protection against splashing water is
_____.
IP36
IP44
IP54
IP64
The three basic logic functions are _____.
YES, NO, and GO
AND, OR, and NOT
STOP, START, and HOLD
FORWARD, BACK, and STOP
A circuit breaker can be used as the controller for
small stationary motors under _____.
1hp
1⁄2 hp
1⁄3 hp
1⁄8 hp
Reversing a three-phase motor can be done by
_____.
reversing the L1 and L3 power leads
reversing the L1 and L2 power leads and the L2
and L3 power leads
adding a start capacitor
spinning it in the desired direction before
applying power
