Study with the several resources on Docsity
Earn points by helping other students or get them with a premium plan
Prepare for your exams
Study with the several resources on Docsity
Earn points to download
Earn points by helping other students or get them with a premium plan
Journeyman Lineman Test Questions with Correct AnswersJourneyman Lineman Test Questions with Correct Answers
Typology: Exams
1 / 15
This page cannot be seen from the preview
Don't miss anything!
Delta Secondary Voltages? Delta doubles (Phase to phase is always 2 x Phase to neutral.) WYE Secondary Voltages? Phase to phase is always 1.73 x phase to neutral Shoring and Latter placement? 3 4 5-Shoring Latter extends 3' past rest point At 4' you need a ladder At 5' you need shoring 1 Ladders every 25' What causes resistance in a conductor? The Type: Copper/ACSR, Size, Length, and Temperature (the more heat more resistance.)
How do you take a capacitor off line? Open oil switch or open cutout with load break. The internal resistor should bleed the voltage to 50 volts or less in 5 min. Then shunt and ground the capacitors. What do capacitors do? Improve power factor, when the current is lagging the voltage. Why does a recloser stay energized longer on the 3rd or 4th shot? To allow a fuse to blow if there is a tree fault and also to narrow down the area of the fault after the fuse blows. The reason it holds open is to allow an sectionalizer to open cause it operates under no voltage. What determines the strength of a magnetic field? the current Types of over current protection? Circuit breaker, Recloser-OCR, and Cutout. Can you look at a circuit breaker and determine the line voltage? NO (Because they are not rated in voltage just amps) In CPR how many chest compressions are needed to how many breaths?
At what size do transformers start being subtractive not additive? 200 KVA and up or 8660 Volts. At what depth do you need egress and digress in the ditch? 4ft deep and a latter every 25ft How far back does the spoil pile need to be from the edge of the ditch? 2ft back 5 things that are needed on the Job Briefing? Hazards, Work Procedures, Special Precautions, Energy Source Control, and PPE. How many times does a sine wave cross 0°? 3 Times What is step potential? When one foot is at a different electrical potential then the other. What is touch potential? When you touch something at a different electrical potential from your feet or other hand.
At what kVA do transformers have 4 bushings? Above 100kVA has 4 bushings What do you do with the neutral on a WYE-Delta bank? Float, always What do you do with the neutral on a open wye-open delta? Always tie to system neutral In a delta system phase current =? 1.73 X Line Current, Phase current = Coil Current What needs to be checked before paralleling two transformers? The Impedance needs to be + or - 10% Where should tap changers be set at ? at 100% For normal operation What is the displacement of a WYE-Delta or a Delta-WYE? 30° or 210° What is the displacement of a WYE-WYE or a Delta-Delta bank?
Each transformer carries 1/3 of the 3-Phase load. (If there is a larger Xfmr it can only match smaller Xfmr in 3-phase capacity.) On a single bushing transformer (CSP) where does the other end of the primary coil go? To the tank ground What is an internal fuse? It is the same thing as a cutout fuse just inside the H1 bushing. What's the difference between "240/120" and "120/240" on a transformer name plate? 240/120 is two separate coils 120/240 is one coil What does a bayonet fuse on a padmount transformer de-energize? The primary winding of the transformer (But the transformer bus bar between H1A and H1B is still energized) What does a CT's do to the amps? CT's reduces the amps to 5 What do PT's do to the voltage? PT's reduce voltage to 120v
What is copper loss? Copper loss is resistance (in the wire) What non-flammable gas is put into equipment? SF6 Gas (Sulfur Hexafluoride) How do you calculate load on an open transformer bank? (Load X .57 )= 3-phase load What are regulators? A regulator is a autotransformer (The primary winding is connected across the line, and the secondary winding is connected in series with the load.) How to find taps? Divide Actual/desired. Example if actual is 120v, voltage desired 110v. 120/110 = 1.09 (109%) How do you find KWH consumed? Current Transformer rating 30: Potential Transformer rating 7200: (30/5=6, 7200/120=60, 60X6=360)
weight X load factor = total load Rigging How do you find load on each sling? Load factor / number of slings = load on each sling How to find turns Ratio on polarity check? (Input ÷ difference = turns ratio) 136v output - 120v input = difference is 16v. 120 ÷ 16 = 7. turns ratio = 7.5 to 1 How to find 3-phase load (kVA) on open bank? Kva X .866 = Full load (kVA) Color and voltage of rubber gloves? Class 0-Red Label 1000v Class 1-White Label 7.5Kv Class 2-Yellow Label 17Kv Class 3-Green Label 26.5Kv Class 4-Orange Label 36Kv How do you find watts?
Kva = Watts To find primary transformer Amps at full load? P ÷ E = I (Kva ÷ Primary Voltage = Amps at full load) To find secondary Transformer Amps at full load? P ÷ E = I (kVA ÷ Secondary Voltage = Amps at full load) To find turns ratio? Primary Voltage ÷ Highest output voltage Delta or WYE? WYE likes, Delta dislikes OHM's law? How is the primary coil connected to the secondary coil? magnetic coupling What kind of transfomer is used for series streetlights? And how many amps does it have? Constant current Transformer/6.6 Amps
Power factor is equal to real power divided by ?. apparent power The ratio of active power to apparent power is called the ?. power factor According to OSHA Guidelines, electrical testing of rubber insulating gloves must be done before issue and every ? thereafter. 6 months Capacitance is measured in ?. farads The ratio of the circuit's true power to apparent power is the circuit's ? power ratio Power factor is the ratio of ? to ?. kW peak / kVA peak The four forms of measurement of voltage and current associated with sine waves are average, peak, peak-to-peak, and ?.
RMS (Root Means Squared) What is covered in OSHA 1910.269? General industry-Maintenance What is covered in OSHA 1926? Construction-Line building What can voltage variation be according to NEC?
