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3E051 2-3
Set 2 Book 3
Question | Answer |
---|---|
Electrical cables are installed under roadways using | Concrete encased ducts |
To ensure a sufficient number of spare ducts, you should allow for at least a 25 percent increase in the number of | Cables |
Why must ducts that terminate in a building be sealed | To prevent gases and rodents from entering a building |
What information is marked on manhole covers | Ownership or type of utility |
What is the minimum size of a constructed manhole | 4 feet by 6 feet by 6 feet |
The use of 90 degree bends in duct lines is permitted for | Pole risers |
What is the purpose of a vault | Isolate electrical equipment |
What type transformer is used in a vault | Subway transformer |
Junction boxes located in an underground vault must | Provide a water tight seal |
What specified percentage insulation level is used for medium voltage ungrounded cables | 133 percent |
The mechanical strength of underground cable is not a major concern because the cable is | Not under tension |
What material is used between the conductor and the cable insulation | Strand shielding |
When pulling cable, the snatch block and pullling rope is attached to | The pulling in iron in the manhole |
Which is a determining factor in the spacing between manholes | Cable weight |
Using he winch method, how many people does it take to pull underground cable safely | 5 |
What term describes an underground cable that is brought up through a conduit and attached to an overhead line | Riser |
The device used to terminate high voltage cables is called a | High voltage terminiation |
What is the purpose of a cable end seal | Prevents moisture from entering the cable |
When making a load break elbow, before attaching the crimp connector to the cable make sure you | Align the hole on the end of the connector with the equipment bushing |
What is the next step after sliding the elbow over the connector and cable | Thread the electrode into the connector using the wrench from the elbow kit |
What combustible gases are usually found in manholes | Natural gas or hydrocarbon fuels |
What must you do when work takes place in a manhole that is 15 feet deep or more | Use a power blower for the entire work period |
Which is not a manhole ventilation method | Funnel |
How often must a gas test be made in a confined space | Continuously |
What is the approximate bending radius for underground cable | 5-12 times cable diameter |
For racking purposes, how much straight cable need exist on each side of a cable splice | 6 inches |
What type of tape is used for fireproofing underground cable in manholes | Polymeric elastomer tape |
What type of cable test is made after its installation but before it is placed into service | Acceptance test |
When you perform a maintenance test on a cable, what is the acceptable test voltage | 75 percent of acceptance test voltage |
Power factor tests can be performed at any voltage without exceeding the | Line to ground rating of the cable |
What is the easiest and quickest way to locate a cable fault | Visually |
When you use the MM-1 fault locator or the thumper to locate a cable fault, what signal is produced when you are over the fault loaction | Fault locator signal fades out at the fault, thumper signal increases to the loudest volume |
In many cases, a cable fault is located at a | Splice |
Which cable splice kit requires the most labor to install | Conventional taped splice kit |
What is the preferred method when making splices | Factory pre form splice kit |
What should be your first step when troubleshooting a pad mount transformer | Take a complete set of secondary phase to phase and phase to ground voltage readings |
If tests indicate an off ratio winding, how would you verify whether the problem was in the transformer or not | Take voltage readings on the primary side of the transformer |
Which airfield lights have yellow filters installed for the last 2000 feet of runway | Runway edge lights |
Which airfield lights provide positive identification of the beginning of the operational runway surface for approaching aircraft | Threshold lights |
Which airfield lights are required on all lighted runways | Runway end lights |
Which airfield fixture is unidirectional | Approach |
Which of the follwing items are found on ALSF-2 approaches | 500 foot bar |
What color is used for the taxiway edge light | Blue |
At what minimum distance from the usable landing area does a station beacon also require an identification beacon | 2 miles |
One of the main control panels for the airfield lights is in the vault, where is the other panel located | Control tower |
Approximately how far should the airfield vault be from the runway | 3000 feet |
What should you have available if your system uses 48 volt DC control | An extra power supply module |
How many conductors does the standard control cable for an airfield lighting control system contain | Seven |
Which airfield vault device is used to swap location of control of the airfield lights | Transfer switch |
What airfield lighting control system device compensates for the voltage drop from the tower to the vault | Low burden pilot relay |
What size cable is used for airfield light field circuits | No. 8 |
What type of transformer is used at each airfield light fixture to avoid the problems that are normally associated with series circuits | Isolating transformer |
What is performed before installing a regulator | Pre installation check |
What size counterpoise is used for airfield lighting circuits | No. 4AWG |
When replacing an IL transformer, what must the first listed amperage on the IL match | The maximum amperage output of the regulator |
What feature is common to elevated airfield lights | They are built with frangible construction |
What is the primary purpose of the rotating/airport beacon | To guide the pilot to the airfield |
How many revolutions per minute does the airport beacon turn | 6 |
What occurs when the operating lamp in the airport beacon fails | A reserve lamp is placed in operation automatically |
What voltage is necessary to run the airport beacon | 120/240 volts |
What is the minimum number of hazard beacons used on one side of an extensive or extremely high antenna | Three |
What device can be used to change voltage up or down for the airport beacon lamps | The tap changer in the distribution transformer |
How often must you check the level of the airport beacon base and the beacon motor's gears | Annually |
How often does each strobe light unit flash | Twice each second |
How many brightness steps is the strobe system capable of producing | Three |
What voltage rating is the wire that connects the flash head to the individual control cabinet | 3kV |
When does the hour (elapsed time ) meter operate | When system is operated on high intensity |
Which items still have power when CB1 in the MCC is turned off | None, since this is the power disconnect breaker |
How do you bypass the interlock switch on the Individual Control Cabinet | Pull on the plunger |
How long does it take the flash capacitors to bleed off their charge | One minute |
What is indicated when two skips occur within 100 flashes of the condenser discharge system | A worn out lamp |
Where should you start troubleshooting if you turn the strobe system on and it does nothing | The source of power |
Which of the following is highest priority when troubleshooting the condenser discharge system | Getting the lights to flash in sequence |
The check the coil of a deenergized relay, use a | Ohmmeter |
How are animals prevented from chewing on airfield lighting fixture cords | Fixtures are designed so that no cords are exposed |
What is used to maintain contact with the tower when away from the truck | Hand held radios |
Which approach lighting system maintenance item must be performed daily | Check and record burned out lamps |
When should you check all approach light fixtures for alignment | Semiannually |
Where is the PAPI system loacted | On the left side of the runway |
What calculation is used to determine the load on an airfield regulator | Input current times input voltage times the regulator power factor |
How often are dielectric oil tests made on airfield regulators | Annually |
When you tie together two airfield light circuits for emergency operation, what do you do to prevent regulator overload | Move the control wire from step 5 relay to step 4 relay |
In order to perform a DC hi potential test on an airfield light circuit, what do you do with the leads once you remove them from the airfield regulator | Support both leads and keep them clear of each other and the ground |
When using radios, which tow words should yo uuse to describe circuit conditions | Open/closed |
if a combination of faults exist in an airfield circuit, which faults do you clear first | Grounds |
Ballast voltages in multiple street light circuits usually are | 120 to 480 volts |
What type of light fixture should be placed near hidden entrances | Security light |
In an incandescent lamp, how much consumed energy is lost in the form of heat | 90 percent |
Which lighting system should be considered for retrofit with a more efficient system | Mercury vapor |
What letter represents the American National Standards Institute's special designation code for high pressure sodium lamps | S |
Photocells are used extensively in which type of lighting system | Street lighting |
To ensure that the proper amount of light is provided after fixture installation, check the lighting with a | Light meter |
High pressure sodium lamp cycling usually indicates | The end of normal lamp life |
When troubleshooting a 120 volt photocell, which conductor should provide power to the light fixture | Line (black) |
What lighting system practice results in reduced maintenance costs and increased saftey | Group relamping |