Embed Code - If you would like this activity on your web page, copy the script below and paste it into your web page.

Normal Size Small Size show me how

Motor Control 1 TEST

Motor Control 1 Test Review

Question	Answer
The capacity of ? is determined by the current ratings of their power contacts for continuous and inrush current conditions.	motor starters
Fuses and breakers protect what part(s) of the motor circuit?	Branch circuit and control circuit components.
Overload relays protect what part of the motor circuit?	The motor
Fuses and breakers protect what part(s) of the motor circuit?	Control circuit components and Conductors
NEMA and IEC overload relays respond to overload conditions based on ? .	trip curves
A(n) ? overload relay monitors the current in the motor power circuit through the use of small built-in current transformers (CT's)	electronic
Most thermal and magnetic overload relays are connected in ? with the motor power circuit, so all ? flowing to the motor must flow through the overload.	series / current
Overloads are sized based on motor full load current (FLC), contactor size, the motor service factor (SF), ambient temperature and the class number requirement. T/F	T
Ch1 TEST INFO
Which of the following electrical industry pioneers invented the first practical AC motor?	Nikola Tesla
According to a 1998 Department of Energy survey, what percentage of electricity used in the United States was used to drive electric motors?	63%
What organizations are the standards-setting organizations for motor control devices?	International Electrotechnical Commission (IEC) and National Electrical Manufacturers Association (NEMA)
NEMA's first national standards effort was called the ???	Safe Electrical Cord Program (1929)
The IEC (International Electrotechnical commission) produces standard publications under a number of document formats, what are they?	International Standards (IS), Technical Specifications (TS), Technical Reports (TR), Industry Technical Agreement, Publicly Available Specifications, and Guides
Which standards organization is associated with the International Organization for Standardization (ISO)?	IEC
As a standards organization, which of the following document formats are used with IEC standards?	IS – International Standards and TR – Technical Reports
The two parts of a pushbutton switch are the ? and the contact block.	operator
When installing pushbuttons or selector switches, ? type operators are generally installed in 30.5 mm openings, while ? type operators are generally installed in 16 mm or 22.5 mm openings.	NEMA / IEC
The position of the actuator at which the contacts snap to the operated contact position.	Operating Position (OP)
The distance or angle of the actuator movement beyond the operating position.	Overtravel (OT)
Automatically operated input devices are switches triggered by a change in a ? parameter, such as liquid level, pressure, fluid flow, and material temperature.	process
What are three types of pressure switches?	Positive pressure switch, Vaccuum switch and differential pressure switch.
Both positive and negative pressure devices ? the rise and fall of the pressure and actuate their contacts when the desired pressure, called set point , is reached	monitor
A solenoid is a specific type of ?	electromagnet
A coil of insulated or enamel covered wire with a movable metal core in the shape of a rod made of solid iron, solid, steel, or powdered iron	Solenoid
(CH4) Solenoids convert ? electrical energy directly into linear mechanical motion.	electrical
The machine control relay is an ??? relay that consists of several contacts available with up to 12 contacts.	electromagnetic
The machine control relay have typically 2 to 8 contacts and is also called a ???? or machine tool relay .	heavy duty
Limit switches are the ???? frequently used mechanically operated input devices.	Most
???? pressure switches are actuated when additional gas or liquid is added to the system	Positive
??? Pressure switches measure the difference in pressure from two different sources.	differential
???? and ???? pressure devices monitor the rise and fall of the pressure and actuate their contacts when the desired pressure called "set point" is reaches.	Positive/ Negative
Machine control relays are available in up to how many contacts?	12
Machine control relays provide easy access for ??? maintenance and generally have a long life.	Contact
NEMA Machine Control relay voltages range from ???? to ??? volts. Most 10A some 20A	300 to 600
IEC Machine control relays are ??? volts . Most 10A some 15A	600
Machine control relays are used for extensively for direct switching of solenoids, ????, and motor starters. IEC machine tool relays typically have a life of one million operations and neMA are expected to last at least ???? as long.	contactors/ Twice
The term interposing relay is used to describe a relay which enables the energy in a ? circuit to be switched by the ? circuit in a control system.	high-powered / low-powered
Contacts on relays that can be configured as either normally open contacts or normally closed contacts are called ? contacts.	convertible
The NEMA standard specifies that AC magnetic motor starting devices must function at voltages as low as ? of the rated coil voltage.	85%
Some industrial applications require fuse protection on one ? line and in both ? lines.	secondary / primary
The use of fuses on the primary and secondary side of a control transformer is specified by the ? .	National Electrical Code (NEC)
AC circuits of ? or more must be grounded in accordance with the National Electrical Code® (NEC) Section 250.	50 V
The major difference between the standard for contactors and motor starters is the ???? of the control device for a given motor or resistive load.	sizing
activated switching device, without an overload protection device attached, to switch single phase or three phase AC power or DC power to the load	Manual Contactor
magnetically activated switching device, without an overload protection device attached, to switch single phase or three phase AC power or DC power to the load	Magnetic contactor
magnetically activated switching device, without an OPD attached, to switch power to a load other than an AC or DC motor. Devices have multiple power poles and offer several options to keep the contacts pulled in when coil power is removed. Some manufacturers call these "Definite Purpose" contactors.	Definite purpose magnetic contactor
magnetically activated switching device that includes a magnetic contactor and an attached overload protection device, to switch single phase and three phase power for AC motor control and power for DC motor control	Magnetic motor starter
Manual motor starter are used to control small motors, such as ?????? Horsepower and ?????? horesepower motors, found in commercial and industrial applications.	Fractional and Integral
When the contactor and ? are combined into a single device or separate devices that are wired together, the combination is a motor starter.	overload
???? starters consist of a safety disconnect, short circuit and overload protection, and magnetic motor starter placed in a common enclosure.	Combination
What are the three types of OL relays?	Thermal, magnetic, and electronic
What AC coil voltages are typical for IEC contactors?	24 to 600 V AC
Most magnetic motor starters are supplied with at least one NO auxiliary contact; this contact is used for electrical ? or start pushbutton ? requirements in the control circuit.	hold / sealing
Three types of overload relays, thermal, magnetic, and electronic, with DIFFERENT operational principles, protect the motor from OVERLOAD current. T/F	True
Motor current is proportional to motor load and an INDICATION of the ????? in the windings. Overload relays on the motor starter monitor motor power in the circuit and open the power circuit when excessive motor current occurs.	Heat
CT's
A (timer) device with a preset time period between energizing the timer or applying the input signal and the action of the timer output contacts. During the timing period no change occurs in the timer output contacts.	On Delay Timer
On Delay timer is also called: on energize (DOE), delay on make, and delay on ????	operate
The On Delay time is used to apply or remove power to a load at a pre set time after the on delay timing relay is energized T/F	True
DOE stands for	Delay on Energize
DODE stands for	Delay on De Energize , delay on break, and delay on release.
The notation NOTO which stands for ???? is used for the NO contact operation.	Normally Open Timed Open
Go over page 131
The ???? timer is a timing device that opens and closes a contact using the position of the analog clock hand.	synchronous
The synchronous timer has 15 minute intervals, therefore the best resolution is ?? minutes.	15
The synchronous timer is well suited for work site ??? and sprinkler system control where highly accurate starting and stopping points are not required.	lighting
Most thermal and magnetic overload relays are connected in ? with the motor power circuit, so all ? flowing to the motor must flow through the overload.	series / current
An ? timer is a device with a preset time period between energizing the timer or applying the input signal and the action of the timer output contacts. During the timing period, no change occurs in the timer output contacts.	on-delay
Once initiated, ? contacts change state after a set time period has passed. Once the time has passed, all normally open timed contacts close and all normally closed timed contacts open.	DOE
An ? timer is a device with a preset time period that starts after the input signal is removed. The timer output contacts change when the input signal or external trigger is applied, and the contacts remain in the changed state until after the timing period.	off-delay
Some solid state electronic timers have an accuracy of ???? second.	0.01
Electronic timers have time delays of fractions of a second to ????? minutes	hundreds
What are the three basic steps to troubleshooting timers?	1. Visually inspect for damage or deterreoration 2. verify that the correct power is applied to the timer, 3. verify proper timer contact operation.
Schematic Diagrams use grafic symbols to show connections between ??? and ??? of an electrical circuit.	components and functions

Created by: Shawnt321

"Know" box contains:
Time elapsed:
Retries: