2-2-1 Introduction to Test Instruments Flashcards
All other units of measure are defined and compared to the four basic measurements of length, __?__.
weight, time, and temperature
The Romans refined distance traveled to a unit of length called the __?__.
mile
The basic subunit of the ancient Egyptians’ royal cubit stone is the span.
False
The meter was defined as 1/10,000,000 of the distance of the meridian passing through __?__ from the North Pole to the Equator.
Paris
Mass is used as a standard instead of weight.
True
Weight is often used as a standard because it is universally constant, regardless of latitude.
False
The Babylonian calendar consisted of 360 days. This led to fractions such as 1/60 which are still used in astronomy and for the minutes and seconds of the day.
True
The metric system adopted the __?__ as the standard unit of time measurement.
second
Both Fahrenheit and Celsius thermometers have scales based on the freezing and boiling points of __?__.
water
The absolute zero scale of centigrade is often called the __?__.
Kelvin
The signal word used to indicate a potentially hazardous situation which could result in death or serious injury is the __?__.
warning
Always ensure that the jack position of the test leads corresponds to the setting of the meter function and selector switch before taking a measurement.
True
The main reason for the increase in the use of digital electronic technology is for greater measuring capability.
True
Only a meter marked __?__ can be used when taking a measurement on a circuit that includes solid-state components that distort the shape of AC sine waves.
True RMS
The __?__ feature on a digital multimeter allows a meter to automatically adjust to a higher range setting if the set range is not high enough for the application.
Autoranging
Digital test instruments are less susceptible to noise than analog test instruments.
False
Analog test instruments are less accurate than digital test instruments.
True
When using a test instrument with test leads, the __?__ lead should be connected first.
ground
For maximum safety, personal protective equipment and safety requirements for test instrument procedures must be followed, as specified in __?__, which is one of several standards.
NFPA 70E
The primary purpose of rubber insulating gloves is to insulate the hands and lower arms from possible contact with live conductors.
True
__?__ are an eye protection device with special impact-resistant glass or plastic lenses.
Safety glasses
An arc __?__ is an explosion that occurs when the air surrounding electrical equipment becomes ionized and conductive.
blast
Electricity is the number one cause of fires.
True
Never touch any part of an electrical shock victim’s body when it is in contact with the circuit. When the circuit cannot be turned off, use any __?__ device to free the victim.
nonconducting
Grounding is the connection of all exposed, noncurrent-carrying metal parts to the neutral conductor.
False
__?__ is the process of removing the source of electrical power and installing a lock that prevents the power from being turned on.
Lockout
Lockout/Tagout is normally removed by the __?__, other than in an emergency.
person who installed it
An arc flash is an extremely high-temperature ? produced by an electrical fault in the air.
discharge
Clothing made of synthetic materials, such as rayon, are the only type that are to be worn when working with energized electrical circuits.
False
The __?__ is a federal act that requires all employers to provide a safe environment for employees.
OSH Act
The life expectancy of a test instrument depends on the __?__.
care of the meter
Extra care must be provided to digital test instruments because their movements are susceptible to damage from shock.
False
The resistance of test leads must be less than __?__.
1 Ohm
