Electrical Flashcards
An ammeter is a device that measures
Current
The name “ammeter” comes from the fact that it is a meter used to measure current (in ___________)
Amperes, and thus is called an AMpere METER, or AMMETER.
Some electrical and electronic devices have meters built into them. These meters are known as
in-circuit meters
In troubleshooting, it is usually necessary to use a meter that can be connected to the electrical or electronic equipment at various testing points and may be moved from one piece of equipment to another. These meters are generally portable and self-contained, and are known as
out-of-circuit meters
_______ meters are more versatile than in-circuit meters
Out of circuit meters
the ________ meter can be used wherever you wish to connect it.
Out of circuit meter
Ammeters must always be connected in ________ with the circuit under test.
Series
The two instruments most commonly used to check the continuity (a complete circuit), or to measure the resistance of a circuit or circuit element, are the _______ and the _________
OHMMETER and the MEGGER (megohm meter).
The ohmmeter is widely used to measure ________ and check the continuity of electrical circuits and devices.
resistance
The megger is widely used for measuring ________ resistance, such as between a wire and the outer surface of the _______, and _______ resistance of cables and insulators.
insulation
ohmmeter are connected in_______ with the circuit to be measured
series
A ________ is the most common measuring device used in the Navy.
MULTIMETER
The thermocouple movement uses the current being developed in a thermocouple when the heat of a resistive wire is _______ to the thermocouple.
transferred
Thermocoupler movement will measure only ______
Current
A _______ is the simplest circuit protection device.
fuse
___________ is a condition in which some point in the circuit, where full system voltage is present, comes in direct contact with the ground or return side of the circuit.
DIRECT SHORT
__________ are used in low-voltage, low-current circuits. This type fuse is rapidly being replaced by the circuit breaker.
PLUG-TYPE FUSES
Shipboard fatalities have been reported due to contact with _____ volt circuits.
115 volts
1 mA - _____ is felt.
Shock
At ______ - a person may be unable to let go.
10 mA
100 mA - shock may be ______ if it lasts for one second or more.
fatal
Work on energized systems _______ or greater is prohibited unless approved by NAVSEA.
1000 volts
A _____ is a device that transforms chemical energy into electrical energy.
Cell
The electrolyte is the solution that acts upon the ______. The electrolyte, which provides a path for electron flow, may be a salt, an acid, or an alkaline solution.
electrodes
In the simple galvanic cell, the electrolyte is in a liquid form. In the dry cell, the electrolyte is a ______.
paste
What are the three parts of a cell?
Container, electrolytes, electrodes
What are the two types of cells?
Primary and secondary
A primary cell is one in which the _______ _______ eats away one of the electrodes, usually the negative electrode.
chemical action
A secondary cell is one in which the electrodes and the electrolyte are _______ by the chemical action that takes place when the cell delivers current.
altered
What is another name for the positive electrode?
Anode
What is another name for the negative electrode?
Cathode
The automobile storage battery is a common example of the _______ cell.
secondary cell
When connecting cells in_____, connect alternate terminals together ( to +, to +, etc.)
series
In a _____ connection, all positive cell electrodes are connected to one line, and all negative electrodes are connected to the other.
parallel
The lead-acid battery is one of the most _________ batteries in use today.
common
Specific gravity is the ratio of the _______ of a certain amount of a given substance compared to the weight of the same amount of pure water.
weight
The ________ _________ of pure water is 1.0. Any substance that floats has a specific gravity less than 1.0.
specific gravity
To measure a battery’s _______________, use an instrument called a HYDROMETER.
specific gravity
Distilled water should be added to bring the _________ to the proper level.
electrolyte
If the electrolyte is spilled or splashed on the skin or eyes, IMMEDIATELY flush the skin or eyes with large quantities of fresh water for a minimum of ____________
15 minutes.
