IC1 Questions Flashcards
When using a multimeter to check continuity of the ground conductor from the tool case to the dummy receptacle, be sure the reading is…
Less than 1ohm
What is the max safe voltage of rubber gloves that are labeled with the color white?
7,500V
Who is responsible for understanding and observing safety standards and regulations on board the ship?
All individuals
What publication specifically contains general shipboard safety precautions?
OPNAVINST 5100.19E
What color are warning signs?
Red and white
What color are caution signs?
Yellow and black
When are danger shock hazard signs used?
When voltages are between 30 and 500 volts.
Warning plates are installed in small craft to warn personnel of what potential?
Explosive vapors
What color is a caution tag?
Yellow
What color is a danger tag?
Red
Can equipment with an out of calibration label still be used?
Yes, with extreme caution
Isolated receptacle circuits are designed to limit ground leakage currents to how many milliamperes?
10 milliamperes
Why must you short-circuit the secondary of a current transformer before you disconnect the meter?
To prevent an extremely high voltage build up
When, if ever, is it permissible to block an interlock switch on a piece of equipment?
When authorized by the CO for operational reasons
What do you use to discharge capacitors?
Shorting probe
What class of rubber gloves should be worn when dealing with 5000volts?
Class II
When installing rubber floor matting, you should ensure there are no seams within what minimum distance of an electrical hazard?
3 ft
Why should a dummy outlet be installed near a work bench?
To test the grounding conductors on portable power tools
What is an acceptable resistance reading for the ground connection between the ships hulk and metal frame of a portable electric drill?
1ohm or less
Under normal usage, the maximum length of an extension cord used with portable tools should NOT exceed how many feet?
25 feet
The current coil of a wattmeter or an ammeter must be connected in what way?
In series with the load
In signal generators and oscilloscopes, how are the effects of moisture minimized?
By built in heaters
Before being used on electronic equipment, metallic tools should be insulated by wrapping with what material?
Two layers of rubber tape or vinyl plastic tape, half lapped
If cared for properly, lead acid storage batteries should last for what max period of time?
4 or more years
The charging rate of a lead-acid storage battery being charged should be lowered under what circumstance?
If the temperature of the battery reaches 125 degrees
What is the proper procedure for mixing electrolyte?
Pour the acid slowly into the water
Dry- cell batteries should be removed when the equipment they are used with is going to remain idle for what min length of time?
2 weeks
To remove large fragments of a broken radioactive tube, what should be used?
Forceps
Why should you be extremely cautious when handling a CRT?
Because it’s glass envelope encloses radioactive gas
Before disposing of a CRT, you should break off the tip of the glass vacuum seal with what?
Pliers
What is the proper method for disposing of aerosol dispensers?
Put in approved waste receptacle
What solvents should NEVER be used for cleaning electrical equipment?
Inhibited methyl chloroform
What is the preferred grade of insulating varnish used in the navy?
-clear baking varnish (CB)
What materials should never be used to clean contacts
Steel wool and emery cloth/paper
A fire breaks out in a piece of electrical equipment, what is the first thing that should be done?
De-energize the piece of equipment
Low voltage (115v and below) circuits are NOT dangerous because they do not cause death. ( true or false)
False
The victim of electrical shock by a portable drill should be freed of contact how?
Unplug the drill
What is the purpose of artificial ventilation?
To provide a method of air exchange
To be effective, CPR must be started within what max length of time?
4 minutes
A wound that is often complicated by crushing of the tissues is classified as what?
A laceration
When direct-pressure method is used and fails to stop the bleeding what action should be taken?
Use the pressure point method
What burns are for the most part NOT caused by heat?
Chemical
What is the most important factor in determining the seriousness of a burn?
The extent of the body surface burned
Which of the following is a characteristic symptom of a a secondary- degree burn?
Blistered skin
Hazardous noise areas that produce continuous and intermittent sound levels greater than what min level?
84db
A worker should wear double hearing protection when working around noise sources above what min sound level?
104 db
Exposure of personnel to excessive heat, humidity, and thermal radiation while under a continued work load can result in what?
Heat stress
Heat stroke
Heat exhaustion
Heat stress survey must be ordered when the temperature in a space exceeds what min level?
100 degrees F
To what does the rating of a switch refer?
The maximum allowable voltage and current of the circuit in which the switch is to be used
Switch contacts should be open and closed slowly to minimize arching. (True or false)
False
The single- throw switch has what total number of pole?
Two
What are the voltage and amp ratings of the various types of toggle switches?
20 volts to 600 volts
1 amp to 30 amps
What is the normal contact arrangement of a push- button switch?
Either make or break type
What does the first number in a rotary snap switch designation indicate?
Current rating
For a pile switch, when operated, what terminals are connected together?
2 and 3
5 and 6
A type J multiple rotary switch with five sections has what total number of stationary contacts and moveable contacts?
8 movable
2 stationary
In type 3 JR switch, what total number of moveable wiper contacts are there per section?
One
What is the purpose of the stop deck of a JR?
It enables the switch to be set to a desired number of positions
How does the JL switch compare to the JR switch?
The JL switch is rated the same as the JR switch
What kind of contacts are used in JA switches.
Silver to copper
The JF switch replaces what type of switch?
Toggle switches in the 10/20- switch boxes for sound powered telephone applications
What type of interiors are used in most lever- operated switches
JR
What means is used to distinguish the collision alarm on a submarine?
A star shape
How is a typical pressure- operated switch similar to a typical temperature- operated switch?
- both are single- pole, single throw, and quick-acting switches
- both contain a bellows or diaphragm the works against an adjustable spring
- both contain contacts that are closed automatically by an adjustable spring when a preset value of the operating condition is reached
How is the operating point of a cam- operated mechanical switch varied?
By adjusting the contact gap of the micro switch
How many pairs of terminals are used in water switches?
One
QA
Air- locking Indicator
PW
Clutch- position indicator
DW
Wrong - direction alarm
SP
Shaft- position alarm
LS
Submersible steering- gear alarm
How is the liquid- level float switch changed from normally open to normally closed?
By turning over the magnetic core
What is circuit FH?
Sprinkling alarm systems
Which of the following troubles is caused by excessive tightening of the packing gland nut in a watertight rotary switch?
Improper positioning of the switch
When servicing a pair of copper contacts (one is slightly burned, the other badly burned), which of t he following procedures should you follow?
Replace both contacts
You should NOT attempt to remove the tarnish the forms on silver contacts for which of the following reasons?
Because the tarnish improves the operation of the contacts
How is the coiled a relay that is designed for shunt connection wound?
With a large number of turns of small wire
How are control relays classified?
Open
Semi- sealed
Sealed
What causes the bimetallic strips of a thermal relay to bend when heat is applied?
Lag coil or slug influencing their magnetic properties
What two windings are used in latch-in relays?
Trip coil and reset coil
To close the contacts of an AC shunt relay, a voltage must be applied to what components?
The operating current
What should you use to clean a relay?
Burnishing tool
What type of relay has multiple sets of contacts?
Clapper relay
What total number of adjustment are there on a two- coil, series-type relay?
Two
What type of relays are also known as contractors?
Power relays
The “cone and crater” effect that is associated with relay contacts is caused by what condition?
Current flowing in one direction through the relay
When one of the contacts of a shunt relay is badly pitted, what action should you take?
When one of the contacts of a shunt relay is badly pitted, what action should you take?
When the relay contact springs are bent during cleaning, what action should you take?
Straighten the contact with a point bender
Solenoids are used for which of the following reasons?
To convert electrical energy into mechanical motion
What is the second step in checking an improperly operating solenoid?
Check the energizing voltage
What type of fuse holder will hold two fuses?
FHL10G
