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3E051 2-2
Set 2 Book 2
Question | Answer |
---|---|
Which of these items is NOT a part of a DC motor | Stator |
In a DC motor, how are coil ends from the armature windings attached to the riser | Soldered |
The DC motor with the highest starting torque is the | Series motor |
The DC shunt motor connects the field coils and armature in | Parallel |
What part of a three phase motor is connected to the supply voltage | Stator |
The component of a three phase motor connected to the load is the | Rotor |
The magnetic field of a three phase motor rotor is caused by | Impedance of the stator |
Which motor would have the highest RPM if each were connected to the same power supply | 4 pole motor |
The internal windings of all three phase motors are | Either wye ore delta connected |
Which of the following features describes three phase motors best | Either single or dual voltage motors |
The motor that requires some starting means is the | Single phase AC motor |
A centrifugal switch is use in a single phase motor to | Deenergize the start windings |
The squirrel cage winding has high inductive reactance and is placed beneath the | Wound rotor section |
A single phase motor with external leads numbered T1, T2, T3, T4 is what type | Dual voltage nonreversible |
What should you connect to operate a single phase dual voltage motor on high voltage | Run windings in series |
How many basic types of across the line motor controls are there | Five |
The basic types of overload relays are | Thermal and magnetic |
The methods used to open the contacts on a across the line magnetic controller are | Spring tension and gravity |
What type of motor enclosure is designed to prevent liquids or solids from entering it except at indirect angles | Splash proof |
What type of bearing should be used in a vertically mounted motor | Ball or roller |
When you clean a motor with compressed air, what is the maximum air pressure to use | 25 PSI |
What should be your first check on a motor that seems to be overheating | Ventilation |
If a motor has been operating normally but suddenly stops, you should suspect | Electrical overload |
The end play of a motor should not exceed | 1/64th of and inch |
An indication of an open rotor in a squirrel cage motor is | The motor slowing down under load |
A motor that operates slowly may have a | Deficient voltage supply |
Motor voltage must be within what percent of the voltage rating | 10 |
A woodworking shop would constitute what class of electrical hazard | Class III |
Electrical equipment used in Class I locations must be | Explosion proof |
Sparkproof electrical equipment must be used in what class locations | Class III |
Which of these wiring methods is permitted in Class I, division 1 hazardous locations | Mineral insulated cable |
To prevent explosive materials from passing from one part of an explosion proof conduit system to another, you should use | Sealing compound |
Before working on an electrical system you should always | Deenergize the power to the circuit |
A proper fit between an enclosure and its cover is achieved by | Flat ground joint surfaces |
When you work in a Class I hazardous location, you should use all the equipment listed below EXCEPT | Non sparking metal hand tools |
If work must be done on equipment exposed to hazardous material, the equipment should be | Cleaned and tagged |
How long must the power supply to an emergency light be able to supply voltage | 1 1/2 hours |
According to the NEC, the wiring for emergency lighting systems must be | Independent of the regular wiring used for appliances |
How often should a total discharge of emergency light batteries and recharge be done | Every six month |
If an emergency light battery will not hold a charge, what should you do to it | Replace |
The electric range produces heat by | Passing current through a resistor |
What is the most desirable water heater temperature control setting for general purposes | 150 degrees F |
To prevent others from tampering with switches, you will | Lock and tag them |
If you check a heating element and the ohmmeter reads 0 ohms, the element is | Good |
A signal head may have a maximum of how many signal faces | 5 |
The most common types of detectors for traffic control are | Pressure and loop |
Which of the following do you use on a traffic control system | FM |
The controller operates loop and lead in systems whose total inductance is between | 20 and 70 micronhenries |
Most repairs made in the controller cabinet of a traffic control system are made by replacing | Burned out bulbs |
At least how many hours of backup power should you have on a traffic controller random access memory | 30 hours |
What is the minimum mounting clearance required for the signal head | 15 feet |
The purpose of the motor on a siren for a base warning system is to rotate the siren | 360 degrees |
Which organization is responsible for turning on the base warning siren | Command post |
Your first step in troubleshooting the base warning system should be to check the | Control circuit |
Voltage being present on the load side of the controller on a base warning system means the | Controller is fully operational |
What type of process is corrosion | Electrochemical |
The ions that leave the metal and enter into solution are | Positive |
How many basic forms of corrosion are there | Four |
Where does stray current corrosion cause greatest damage | Where it exits a structure |
At least how many inches of back fill should extend from each end of the anode | 12 |
How often should a structure be checked for depth of pitting | Every two years |
The basic guidance for completing maintenance action sheets is in | AFI 32-1001, Operations Management |
How often must you maintain AF Form 491, Cathodic Protection Operating Log for Impressed Current System | 60 days |
To protect steel or cast iron structures, what should the voltage reading be between the structure and a saturated copper copper sulfate half cell contacting the electrolyte | -0.85 volts |
One of the most important measurements made in cathodic protection (CP) is the single rod probe measurement of the soil resistance between what two points | Structure to electrolyte potential |
What meter should you use to make a structure to electrolyte measurement | High resistance voltmeter |
What is the basic unit of conductivity for water resistivity | Ohms per centimeter |
After the initial series of CP of a galvanic anode system is established, during the first year, how often should the system be checked | Quarterly |
An above normal potential between the half cell electrode and the anode under test shows | That the anode is corroded away |
The two classifications of fire alarm systems are the local and | Central station |
Fire alarm reference material should be maintained in the | Fire department technical services office |
When troubleshooting fire alarm systems, where do the most frequent problems occur | Wire termination points |
What are the two main classes of intrusion detetors | Point and area |
Repair of intrusion detection systems should always be done in accordance with | Manufacture's specifications |