Electrical Auxiliaries
Aircraft batteries are rated according to what rate of discharge?
1 hour
What are the two sections of the ultrasonic cleaner used for?
1. Cleaning 2. Rinsing and drying
On a small boat what is the adjusted specific gravity of a fully charged battery?
1.210 to 1.220
What is the corrected specific gravity for a battery whose electrolyte temperature is 89 degrees? where the uncorrected reading is 1.212
1.215
What is the corrected specific gravity reading for a battery whose electrolyte temperature is 74 degrees? Where the uncorrected reading is 1.220
1.217
If you want to know the rating of a lead acid storage battery you would normally use what hourly discharge rate?
10 hour rate
The oil pressure safety switch is designed to secure the refrigeration compressor if the oil pressure drops to what minimum value?
12 psi
What voltage is used to operate the components of the control circuit?
120 VAC
When operating in the automatic 120 setting the compressor is set to start and stop at what pressure ?
120 psig rising, 105 psig falling
What is the maximum temperature of the electrolyte in any cell?
125 degrees F or 52 degrees c
When operating in the automatic 125 setting the compressor is set to start and stop at what pressure?
125 psig rising, 110 psig falling
What is the ratio of the speed for the starting motor to that of the engine?
15 to 1 (1500 rpm to 100 rpm)
If the power fails when the anchor and chain are being lowered the electric brake is designed to hole what percentage of the rated load?
150%
In a forklift, thermal switches serve to protect the drive and steer motor circuits by opening if what minimum motor frame temperature is reached?
225 degrees F
The rudders have a maximum working angle of what numbers of degrees left and right from the middle ship's position?
35 and 35
The capstan is designed to heave what size line at what speed?
6 inch at 50 ft/minute
What is the normal dry weight load capacity of the washer extractor?
60 pounds
What voltage is used to operate the wiper motor?
68 to 115 VDC
What is the standard temperature of batteries in regards to specific gravity?
80 * F
What features de ices the window served by the wiper?
A 36 watt heating element in the wiper arm
What elevator component slows the elevator once it reaches the desired level?
A cam operated limit switch switches the motor to a lower speed just before the desired level
What are the components of the receiving unit of the receiving ship?
A king post, a receiving head, an elevator, a carriage return hydrualic power unit and a remote control console
How are storage batteries rated?
According to their rate of discharge and ampere-hour capacity
How do you correct a specific gravity reading of a storage battery ?
Add 1 point to the reading for each 3 degrees above 80. Subtract 1 point to the reading for each 3 degrees below 80.
Most batteries are rated according to a 10 hour rate of discharge except
Aircraft and some radio
What method should you use to mix electrolytes?
Always pour acid into the water
In a floating charge the charging rate is determined by? As opposed to?
Battery voltage rather than by definite current value
What is the most frequent trouble with electric cooking equipment in the galley?
Burnt contacts
What are the three major components of a window wiper?
Control box assembly, drive unit, wiper arm
What principle is the basis for the operation of the vent fog precipitator?
Electrostatic precipitation
What is the advantage of using solid state control circuitry integrated with magnetically operated devices to regulate the speed of the series driven motor in an electric forklift?
Enables the generator to handle heavy loads at slow speeds with large battery currents
The deep fat fryer must not be fused but connected to a?
External circuit breaker equipped with a shunt trip element
The magnetic brakes of the electric anchor windlass provide what safety feature?
Hold the load if power fails
Elevators are prevented from being operated from more than one location by the installation of what components?
Interlocked pushbutton stations
The washer extractor should always be loaded to capacity before operating for what reason?
Lighter loads may fail to distribute the clothes properly
The low pressure air compressor has what total modes of operation?
One manual and two auto (low and high)
The suction pressure switch is set to open and close at what pressure?
Open: 5 in HG Close: 8 psig
On an air compressor what condition is indicated by the enable running light?
Power is available to the compressor
What is the purpose of slack cable switches?
Prevents the elevator operation if the cables become loose
What is the purpose of the helm wheel indicator?
Provides a mechanical indication of the rudder command position
What is the purpose of the rudder angle order system?
Provides a nonverbal means of communicating rudder commands from the pilot house to the steering gear room
What is the purpose of the rudder angle display system?
Provides rudder position information to operators
What is the purpose of the portable steering control unit?
Provides the option of steering from either the port or starboard bridge wing
What is specific gravity?
Ratio of the weight of a certain volume of liquid to the weight of the same volume of water
What component compensated for temperature changes?
Resistor R5
On a refrigeration system timing relays provide what safety feature?
Secure the refrigeration after 10 seconds if no oil pressure develops
What are the two major units of the unrep system?
Sending and receiving
What compressor component operates to allow the flow of the injection water?
Servo valve SV1
What means is used to operate the brake and clutch assemblies?
Ship's service compressed air
What are the purpose of over travel switches?
Stops the elevator if it should fail to stop at the uppermost level
What is the purpose of motor overloads?
Stops the motor to protect it from an overcurrent condition
The output of the battery charger is determined by what component?
Switch s3
What advantage, if any, is gained by using a dc motor as a pilot motor?
The DC pilot motor makes an infinite number of platform speed available which range from 3 to 90 feet per minute
What safety feature is incorporated into a precipitator to prevent electrical shock?
The access cover safety switch
When the doors are opened on the m series convection over the fan motor and heating elements are de energized because?
The door interlock switch opens
Where is the ship's control console located?
The pilothouse
On a starting motor what caused the pull in coil to de energize once the solenoid switch is closed?
The pull in coil is shorted by the plunger disk closing the start contacts
When an electrolyte is heated what happens to its specific gravity?
The reading is lowered
What principle permits the ultrasonic cleaner to operate with very little loss of strength?
The relative incompressibility of all liquids
An equalizing charge on a battery is continued for four hours until which conditions are met?
The specific gravity of all cells show no change
The functions performed in electronic elevators by limit switches, relays and contactors are performed in electronically controlled elevators by?
The static logic panel
What are components of the steer motor power circuit in an electric forklift?
The steering motor and contacts of the steer relay coil
The specific gravity of battery electrolyte is the ratio of what electrolyte components?
The weight of a specific volume of acid to the weight of the same volume of water
What component acts to delay compressor shutdown for 10 minutes once a discharge pressure of 125 psig is reached?
Timing relay 1TR
What is the purpose of the ram tensioner?
To help the highline winch operator keep the highline tight during unrep operations
What is the purpose of the heater in the control circuit?
To keep the oil of the compressor warm
What is the purpose of the elapsed time meter?
To keep track of the time a compressor is operated
What is the purpose of the shaft torsionometer system?
To measure the torque on the propulsion shaft
What is the purpose of the controlled torque coupling?
To prevent excessive stress when the anchor is being housed
What is the purpose of the sensing heads mounted up and down the elevator trunk?
To stop and slow the elevator, to prevent the elevator from overspeeding, to prevent overtravel
By what means are shaft hp readings displayed in remote areas of the ship?
Torque
The tank of the ultrasonic cleaner has what total number of sections?
Two
Which of the following electric galley ranges are currently used?
Type A (36 in), type B (20 in), type C (30 in)
When is a normal charge of battery complete?
When the specific gravity is within five points of the specific gravity of the previous charge
Freeze storerooms and chill storerooms are maintained at what temperature?
0 degrees and 33 degrees F
What is the specific gravity of pure water?
1.00
The oil pressure safety switch will stop the compressor if the oil pressure at start up does not build to what minimum psi?
18 psi
What is the heating range of the electric griddle?
200 to 450 degrees F
In an emergency battery charge, the charge starts where?
At a much higher rate than is normally used for charging
What is the most common cause of failure in any hydraulic system?
Dirty oil
When is the automatic injection system used?
During formula mode
Which of the following battery conditions may be caused by a high charging rate?
Excessive gassing
Which of the following means can be used to control the operation of the steering gear?
Hand electric, autopilot, emergency control and manual mode
What is the purpose of timing relay TR?
It opens after a 10 second time delay to de energize the compressor if oil pressure has not caused oil pressure switch OP to close its contacts
What are emergency stop switches?
Located at each level served, used to stop the elevator in an emergency
What is the most common throw of convection oven used aboard ship?
M series
What action should you take to prevent a small boats from overheating
Operate the starting motor for 30 second periods at 2 minute intervals
The starting current on most small boats is?
Over 600 amperes
What compressor component operates to drain the dehydrator condensate sump?
Solenoid valve (SV7)
If an elevator platform over-travels in the down direction which of the following devices help to prevent damage to the platform and hull?
Spring bumpers
When an electrolyte is cooled what happens to it's specific gravity?
The reading is raised
In electrohydraulic elevators speed changes are accomplished by what means?
Varying the stroke of the hydraulic pump
You have spilled battery acid on your arm. What is the first step you should take?
Wash the area throughly with fresh water
