CWEA E1/E2 EXAM STUDY GUIDE QUESTIONS WITH
COMPLETE SOLUTIONS
1) The abbreviation SCADA stands for:
a. Safety Control and Data Answering.
b. Supervisory Control and Data Acquisition.
c. System Computer and Digital Analog.
d. Self Contained and Data Acquisition. -- Correct Answer ✔✔ b Supervisory
Control and Data Acquisition
2) Communicating process data to and from the SCADA computer is the purpose of
the:
a. conditioning system.
b. transmitting system.
c. control system.
d. interface system. -- Correct Answer ✔✔ d interface system
3) Distribution protection usually consists of two elements, protection of both:
a. equipment and circuit.
b. personnel and equipment.
c. wire and control relay.
d. ground fault and current. -- Correct Answer ✔✔ a equipment and circuit
4) What is the current in amperes of a 120-volt circuit with a resistance of 60 ohms,
using Ohm's Law?
, a. 0.5 amperes
b. 2.0 amperes
c. 30 amperes
d. 10 amperes -- Correct Answer ✔✔ b 2.0 amperes
Solving for I:
I = ER Substituting values into the equation:
I = 120 volts/60 Ohms = 2 amperes
5) What is the current for a 120-volt circuit with a 1440-watt load?
a. 0.083 amperes
b. 10 amperes
c. 12 amperes
d. 15 amperes -- Correct Answer ✔✔ c 12 amperes
Since P = EI, current can be determined as I = P/E
Substituting values into the equation:
I = 1440 watts /120 volts = 12 amperes
6) What is the current of a circuit that consumes 625 watts through a 12.75-ohm
resistor?
a. 3.8 amperes
b. 7 amperes
c. 49 amperes
d. 175 amperes -- Correct Answer ✔✔ b 7 amperes
E = IR and P = EI
Substituting the first equation into the second:
P = (IR)I
P = I Squared x R Solving for I:
I Squared = P / R
I = SqRt P/R
I = SqRt 625/12.75
I = SqRt 49
I = 7 amps
, 7) What is the ampere load of a single-phase 1/2 horsepower 115-volt motor, if the
motor has an efficiency rating 92% and power factor of 80%?
a. 9.5 amperes
b. 2.4 amperes
c. 4.4 amperes
d. 78.1 amperes -- Correct Answer ✔✔ c 4.4 amperes
Use the formula I = 746 x horsepower / voltage x efficiency x power factor,
where I is the current.
I = 746 x 0. x 0.92 x 0.80 = 4.4 amperes
8) A 230-volt single-phase circuit has a 12-kilowatt power load and operates at 84%
power factor. What is the current?
a. 43 amperes
b. 52 amperes
c. 62 amperes
d. 70 amperes -- Correct Answer ✔✔ c 62 amperes
the formula
I = kilowatts x 1.000 / voltage x power factor
where I is the current.
I = 12 x 1. x 0.84 = 62 amperes
9) The difference between the measurement signal and the set point is called the:
a. gap.
b. error.
c. feedback.
d. span. -- Correct Answer ✔✔ b error
10) The signal pressure is usually directly proportional to the process:
a. span.
b. level.
c. variable.
d. loop. -- Correct Answer ✔✔ c variable
COMPLETE SOLUTIONS
1) The abbreviation SCADA stands for:
a. Safety Control and Data Answering.
b. Supervisory Control and Data Acquisition.
c. System Computer and Digital Analog.
d. Self Contained and Data Acquisition. -- Correct Answer ✔✔ b Supervisory
Control and Data Acquisition
2) Communicating process data to and from the SCADA computer is the purpose of
the:
a. conditioning system.
b. transmitting system.
c. control system.
d. interface system. -- Correct Answer ✔✔ d interface system
3) Distribution protection usually consists of two elements, protection of both:
a. equipment and circuit.
b. personnel and equipment.
c. wire and control relay.
d. ground fault and current. -- Correct Answer ✔✔ a equipment and circuit
4) What is the current in amperes of a 120-volt circuit with a resistance of 60 ohms,
using Ohm's Law?
, a. 0.5 amperes
b. 2.0 amperes
c. 30 amperes
d. 10 amperes -- Correct Answer ✔✔ b 2.0 amperes
Solving for I:
I = ER Substituting values into the equation:
I = 120 volts/60 Ohms = 2 amperes
5) What is the current for a 120-volt circuit with a 1440-watt load?
a. 0.083 amperes
b. 10 amperes
c. 12 amperes
d. 15 amperes -- Correct Answer ✔✔ c 12 amperes
Since P = EI, current can be determined as I = P/E
Substituting values into the equation:
I = 1440 watts /120 volts = 12 amperes
6) What is the current of a circuit that consumes 625 watts through a 12.75-ohm
resistor?
a. 3.8 amperes
b. 7 amperes
c. 49 amperes
d. 175 amperes -- Correct Answer ✔✔ b 7 amperes
E = IR and P = EI
Substituting the first equation into the second:
P = (IR)I
P = I Squared x R Solving for I:
I Squared = P / R
I = SqRt P/R
I = SqRt 625/12.75
I = SqRt 49
I = 7 amps
, 7) What is the ampere load of a single-phase 1/2 horsepower 115-volt motor, if the
motor has an efficiency rating 92% and power factor of 80%?
a. 9.5 amperes
b. 2.4 amperes
c. 4.4 amperes
d. 78.1 amperes -- Correct Answer ✔✔ c 4.4 amperes
Use the formula I = 746 x horsepower / voltage x efficiency x power factor,
where I is the current.
I = 746 x 0. x 0.92 x 0.80 = 4.4 amperes
8) A 230-volt single-phase circuit has a 12-kilowatt power load and operates at 84%
power factor. What is the current?
a. 43 amperes
b. 52 amperes
c. 62 amperes
d. 70 amperes -- Correct Answer ✔✔ c 62 amperes
the formula
I = kilowatts x 1.000 / voltage x power factor
where I is the current.
I = 12 x 1. x 0.84 = 62 amperes
9) The difference between the measurement signal and the set point is called the:
a. gap.
b. error.
c. feedback.
d. span. -- Correct Answer ✔✔ b error
10) The signal pressure is usually directly proportional to the process:
a. span.
b. level.
c. variable.
d. loop. -- Correct Answer ✔✔ c variable
