ECP 2020
What is the resistance of the conductor if the conductor voltage drop is 3.6 volts and current flowing through conductor is 18 amperes?
.2 ohms
How many watt-meters are required to measure the power in balanced three phase star connected circuit?
1 WATT METER
For stationary small motors rated less than .................., the branch circuit over current device may serve as a controller.
1/8 HORSEPOWER
Small motors rated not more than ................. may use a branch circuit over current protection device as the controller.
1/8 horsepower
In a metal wire-ways, the distance between supports shall not exceed .............. ft.
10
What is the minimum size THWN branch circuit conductor required for a 20 HP, 480-volt, 3 Phase Induction type squirrel cage motor with nameplate FLI of 26.5 amps?
10 AWG
In a metal wire ways the distance between supports shall not exceed ..... feet.
10 FEET
What is the minimum size THWN branch circuit conductor required for a 20 HP, 480-volt, 3 Phase Induction type squirrel cage motor with nameplate FLI of 26.5 amps?
10 awg
For a single family dwelling unit what is the minimum allowable current rating of 3-wire service-entrance conductors?
100 amps Refer: NEC code 230.42(B) Ungrounded conductors rating for specific installations not to be smaller than the disconnecting means Refer: NEC code 230.79 (C) For a single family dwelling unit the service disconnecting means shall have a rating not less than 100 amperes
EMT shall be securely fastened in place at least every ..............
10FT
What is the smallest size copper wire required for a service entrance conductor supplying limited loads of a single branch circuit?
12 AWG NEC 230.31 B
Over head conductors for festoon lighting shall not be smaller than .............. .
12 awg
The voltage shall not be greater than .............. to supply listed electrical discharge lightening in dwelling units, hotels and motels REMEMBER THIS ONE
120 VO,TYS 210.6 A
The maximum voltage rating of plug fuse is .............. volts
120 VOLTS SHOULD BE 125
The voltage shall not be greater than .............. to supply listed electrical discharge lightening in dwelling units, hotels and motels?
120VOLTS
The ampacity of branch circuit conductors between the controller and multi speed motor shall not be less than .............. percent of the current rating of the windings.
125 PERCENT
The vertically run metal wire-ways shall be surely supported at intervals not exceeding ............. ft of wire way and shall not have more than one joint between supports.
15
For a residence having a single branch circuit with a limited load what is the minimum size of service is required?
15 AMP MIN
What is the minimum standard rating for fuses and inverse time circuit breakers?
15 AMPERES
For a residence having a single branch circuit with a limited load what is the minimum size of service is required?
15 AMPERES 230.79A
What is the maximum standard over current device rating used to protect instrument circuits located in a panel board?
15 AMPERES OR LESS 408.52
What is the delay time permitted to start emergency generators in-case of normal power supply failure?
15 MINUTES
What is the maximum standard over current device rating used to protect instrument circuits located in a panel board?
15 amps 408.52
A singe motor is driving 40 volts generator having an over current protection. if the same can also protect the generator when the generator is delivering not more than ...................... percentage of its full load current
150 PERCENT
A singe motor is driving 40 volts generator having an over current protection. if the same can also protect the generator when the generator is delivering not more than ...................... percentage of its full load current
150 PERCENT 445 GENERATORS
What is the resistance of 80 watt Light bulb rated at 120 volts?
180 OHMS
Fuel cell systems should supply emergency load for not less than ........... hours
2 HOURS
The minimum spacing between wood or other combustible materials and an incandescent lamp shall be ........ inches
2 INCHES 600.9C
What is the maximum size fuse allowed to protect 12 AWG THW copper branch conductor?
20 AMPERES 240.4 D 5
If 30 ampere or less snap switches are equipped in panelboards, they must be protected not in excess of:
200 AMPS
If a 30 amperes snap switch is used as disconnecting means of a 2-horse power motor, what shall be the maximum full load current of the motor?
24 AMPS 430.109C2
How many terminals does a potentiometer have?
3
The Minimum working clear distance in front of the enclosed equipment operating at a voltage 240 volts is ................ feet
3 FEET
A continuous load is load where the maximum current is expected to continue for ............ hours or more.
3 hours or more
A transformer has an efficiency of 95 percentage which works at 120V , 3.6KVA .if the secondary voltage is 240V then what is it's rated primary current?
30 AMPS ASKING FOR PRIMARY CURRENT ONLY
A transformer having 1600 turns in primary winding and 400 turns in secondary winding is supplied with 120 volts AC. What is its secondary voltage.
30 volts
A transformer having 1600 turns in primary winding and 400 turns in secondary winding is supplied with 120 volts AC. What is its secondary voltage.
30VOLTS
For a 300 ampere electrical circuit, what is the minimum size copper equipment grounding conductor as per NEC?
4 awg look at table 250.122
When the single phase air conditioner rating is less than .......... at 240 volts can be considered as single motor unit in determining branch circuit conditions.
40 amps
If the replacement compressor motor draws 35 amperes current, what is the minimum rating for disconnecting means used to protect the motor?
430.110 (I)2
If a single phase motor full load current is 30 Amperes, what is the dual element fuze size to be used as motor branch circuit short circuit protection?
50 AMPERES
The sealing compound which seals against passage of gas or vapors through the seal fitting shall not have a melting point of less than ____________ degrees C
501.15[C][2] 93 DEGREES C
What is the maximum constant wattage per linear meter allowed for heating cables embedded in concrete?
54 nec 2014 424.44a
A 8 AWG conductor is suitable to use at maximum ............ KW supplied with a 120 volts power source?
6
How many number of service disconnects per service are allowed to be grouped in any one location?
6
What shall be the maximum weight of the lightening fixture when it is supported only by the screw shell of the lamp holder?
6 lbs
In a Electrical circuit , the lamp resistance is 260 ohms and the ammeter in circuit indicates 5mA. What is the power dissipated in lamp?
6.5W
Which of the following wiring methods that can be used for underfloor wiring in computer room in a building?
645.45 e electrical non metallic tubing All the options are correct Rigid conduit electrical metallic tubing
What is the minimum voltage percentage that a storage battery should supply to emergency load in case of normal power supply failure?
87.5%
What is the minimum percentage rated voltage that a storage battery should supply the emergency load?
87.5PERCENT
A reliable conductor to ensure the required electrical conductivity between metal parts required to electrically connected is termed as ......................
BONDING CONDUCTOR NEC REFERENCE 100.1 DEFINITIONS
Four conductors are made up of four different metals with same dimensions, which of the following metal will offer lower resistance for flow of current?
CHOICES GOLD SILVER AL AND SOMETHING ELSE ITS SILVER
Class II locations are those that are hazardous because of the presence of ......................
COMBUSTIBLE DUST
The demand factor is the ratio of the maximum load demand of a system to the total continuous load.
FALSE NEEDS TO BE THE TOTAL CONNECTED LOAD
All 15,20 amperes receptacle outlets installed in bathrooms of dwelling units shall always require ...........................................
GFCI protection
What must be provided for all working spaces above service equipment, switchboards and panel boards?
ILLUMINATION
When an electrical circuit tested with ohmmeter, a open circuit is indicated by a reading of ......................
INFINITY
What color bands should be found on a 3201Ω resistor with a tolerance of +-1%?
Incorrect 3 (orange)2 (red)10(2) = redtolerance = brown
A 230 volts electric heater produces ............ when it is supplied by 208 volts?
LESS HEAT
The circuit conductor resistance varies with .....................
MATERIAL
Which of the following meter is used to measure resistances in the circuit?
MEGAOHMER
In an Electrical circuit if the current remains the same and resistance increases, the circuit will consume .............
MORE POWER
What is the corrected ampacity of a 2/0 THWN conductors in a dry location. If the ambient temperature of location is 400C?
NEC Table 310.15(B)(16) Conductor ampacity of 2/0 at dry location (900C)= 195 Amperes NEC Table 310.15(B)(2) The correction factor at ambient temperature (450C) = 0.87 Corrected ampacity = 0.87*195 =170 Amperes
The following lamp holder is approved to be installed in either a damp or wet location?
ONE LISTED FOR WET LOCATION
Except AC Generator exciters, all the constant AC voltages should inherently designed with ............................ protection.
OVERLOAD
A transformer has an efficiency of 95 percentage which works at 120V , 3.6KVA .if the secondary voltage is 240V then what is it's rated primary current?
Primary current = 3600/120 = 30 amperes
If a DC power supply is supplied to primary of a transformer then .........................
Primary winding of transformer may burn out
In a direct current electric circuit, which of the following effect the current flow?
RESISTANCE
What is the maximum continuous load that can be connected on a 240 volts 30 amperes circuit using two 10 AWG conductors?
Refer : NEC 210.20(A) Circuit conductors should be rated at 125% connected load which is continuous. Refer NEC Table 310.15(B)(16) 8 AWG conductors maximum ampacity is 30 amperes The maximum continuous connected load = 30 / 125% = 24 amperes
When branch circuits used at outside, the size of overhead conductors for 600 volts or less, for spans upto 50 feet, shall not be less than ............. copper.
Refer : Section : 225.6(A)(1) For Copper it is NO.10for aluminum it is NO 8
What is the minimum size of THWN conductors required for single phase 10 HP motor connected to 240 volts supply?
Refer: NEC Table 430.248 FLI current of single phase 10 HP motor at 230 volts = 50 amperes Refer: NEC 430.22 Minimum conductor ampacity = 50 * 125% = 62.5 amperes Refer: NEC Table 310.15(B)(16) 6 AWG THWN Copper with 65 amperes capacity at 75 0C is suitable conductor for the motor
If a single phase motor full load current is 30 Amperes, what is the dual element fuze size to be used as motor branch circuit short circuit protection?
Refer: NEC Table 430.52Dual element fuze size = 175% of FLC30 * 1.75 = 53 amperesThe next Lower size = 50 Amperes
A 440 volts motor has a full load current of 34 amperes. what size disconnecting means is required?
Refer: Section 440.12(A)(1) The rating of disconnecting means is 115% of full load current.34 * 1.15 = 39.1 amperes.The nearer rating is 40 amperes.
A concealed conductor in electrical wiring means:
Rendered inaccessible by the structure or finish of the building
A quick recovery Electric heater is rated at 4500 W and operated at 120 V, What will be the rating of circuit breaker to be used to protect it?
The ampere current drawn by electric heater = power / supply voltage = 4500/120 = 37.5 amperesThe circuit breaker rating should be 150% full load current150% * 37.5 = 56.5 amperes. The nearest one is 60 amperes. 422.11CF2
A quick recovery Electric heater is rated at 4500 W and operated at 120 V, What will be the rating of circuit breaker to be used to protect it?
The ampere current drawn by electric heater = power / supply voltage = 4500/120 = 37.5 amperesThe circuit breaker rating should be 150% full load current150% * 37.5 = 56.5 amperes. The nearest one is 60 amperes. LOOK AT NON MOTOR APPLIANCES SECTION
The resistance of a No 12 conductor is 0.2 ohms with a current flow of 12 amperes. What does it cost per one year for the power loss in the conductor if the electricity cost is 8 cents per KW?
The power loss in conductor = I2 R = (12 * 12 ) * 0.2 = 28.8 watts / hour Total cost of power loss for year = (28.8 * 24 * 365 * 8 ) / 1000 = 2018.3 cents = $ 20.18
Enclosures, cabinets, cut boxes installed in wet locations shall be ...............
WEATHERPROOF
The following materials shall not be used as Grounding electrodes.
aluminum
Which of the following is connected in series with the load to measure the required parameter?
ammeter
The interior of any dip tank can be considered as ................... location
class 1 division 1
A 2 KW electric kettle takes 6 minutes to boil. how much does it cost to boil it once a day for 30 days at 21 c/kwh?
cost = power in KW * hours used * cost per KW= 2 * 0.1*30 *0.21= $2.52
Which of the following each unit must always required a 20 ampere laundry circuit?
industrial wash room Dwelling unit THIS ONE Commercial utility room Motel unit
If the panel board rating is 100 amperes, what shall be the over current device rating located in panel board?
less than 100 amperes Refer NEC 408.36 The over current device rating must not be greater than panel board rating in which it is located
What is the minimum size secondary conductor required for a 2 wire 480 volts/ 120 volts transformer rated at 2.3 KVA with 750C temperature at terminals?
no. 14 awg
When an electrical circuit tested with ohmmeter, a short circuit is indicated by a reading of ......................
o ohms
The ungrounded ducts or conduits should be sealed before entering buildings.
true 230.8 prevents unwanted gases from entering building