SLTC PRACTICE EXAMS 2025/2026 QUESTIONS AND
SOLUTION RATED A+
✔✔There are three types of aluminum conductors: - ✔✔1. ACSR (aluminum conductor
steel reinforced)
2. AAC (all aluminum conductor)
3. AAAC (all aluminum alloy conductor)
✔✔True / False: Bundled conductors means that the use of no more than one
conductor is used to form a single phase. - ✔✔False - Bundled conductors means that
the use of MORE than one conductor is used to form a single phase.
✔✔The substation serves 3 basic purposes: - ✔✔1. Switching equipment and circuits in
and out of the system.
2. Voltage transformation
3. Voltage control
✔✔True / False: CT's current transformers measure and reduce the voltage levels in the
lines. - ✔✔False - CT's current transformers measure and reduce the CURRENT levels
in the lines.
✔✔True / False: Current Transformers are connected to relays that allow breakers to
open under over-current or fault current conditions. - ✔✔True
✔✔True / False: Primary windings of he CT's are connected in series with the conductor
carrying the current to be measures or controlled. - ✔✔True
✔✔True / False: PT's (potential transformers) measure current and step down the
circuits current flow to a desired secondary current. The lower secondary voltage is
used for metering purposes and control circuitry. - ✔✔False - PT's (potential
transformers) measure voltage and step down the circuits voltage to a desired
secondary voltage. The lower secondary voltage is used for metering purposes and
control circuitry.
✔✔Control house is also called the: - ✔✔Dog house
✔✔Control houses contain equipment such as: - ✔✔1. Switchboard panels
2. Batteries
3. Battery chargers
4. Supervisory controls
5. Power line carrier
6. Meters
7. Relays
, ✔✔Why are DC Batteries kept in the control centers? - ✔✔To control equipment if
power is lost at the substation
✔✔The ground grid is a very critical element of the substation and is designed to
provide the following functions: - ✔✔1. Provide a path to ground for lighting
2. Provide a ground for all substation equipment
3. Ensure the safety of workers in the station by limiting the ground potential differences
4. Ensure the safety of the public
5. Provide a ground source for all lines coming in and out of the substation
✔✔The most common type of primary phase configuration is: - ✔✔WYE configuration
✔✔How many wires are in a WYE configuration? - ✔✔3 phases and a neutral (4 wires)
✔✔True / False: The neutral is grounded both at the substation and at every pole that
has a provided pole ground. - ✔✔True
✔✔Some of the most common distribution voltages are: - ✔✔2,400/4,160 volts
7,200/13,200 volts
12,000/20,800 volts
14,400/24,500 volts
19,900/34,500 volts
✔✔What number comes first? Phase to Phase or Phase to Ground? - ✔✔Phase to
Ground
✔✔What number comes second? Phase to Phase or Phase to Ground? - ✔✔Phase to
Phase
✔✔True / False: A Delta is older and less common. - ✔✔True
✔✔Is a Delta a 3 or 4 wire system? - ✔✔3 wire
✔✔Does a Delta system of a WYE system need help? - ✔✔Delta
✔✔Does a Delta system have a neutral? - ✔✔No
✔✔True / False: Transformers in a Delta system require 2 phases to their top bushing
while in a WYE system they only require 1. - ✔✔True
✔✔What are the two types of distribution layouts? - ✔✔Loop and Radial
✔✔What is more reliable? Loop or Radial? - ✔✔Loop
SOLUTION RATED A+
✔✔There are three types of aluminum conductors: - ✔✔1. ACSR (aluminum conductor
steel reinforced)
2. AAC (all aluminum conductor)
3. AAAC (all aluminum alloy conductor)
✔✔True / False: Bundled conductors means that the use of no more than one
conductor is used to form a single phase. - ✔✔False - Bundled conductors means that
the use of MORE than one conductor is used to form a single phase.
✔✔The substation serves 3 basic purposes: - ✔✔1. Switching equipment and circuits in
and out of the system.
2. Voltage transformation
3. Voltage control
✔✔True / False: CT's current transformers measure and reduce the voltage levels in the
lines. - ✔✔False - CT's current transformers measure and reduce the CURRENT levels
in the lines.
✔✔True / False: Current Transformers are connected to relays that allow breakers to
open under over-current or fault current conditions. - ✔✔True
✔✔True / False: Primary windings of he CT's are connected in series with the conductor
carrying the current to be measures or controlled. - ✔✔True
✔✔True / False: PT's (potential transformers) measure current and step down the
circuits current flow to a desired secondary current. The lower secondary voltage is
used for metering purposes and control circuitry. - ✔✔False - PT's (potential
transformers) measure voltage and step down the circuits voltage to a desired
secondary voltage. The lower secondary voltage is used for metering purposes and
control circuitry.
✔✔Control house is also called the: - ✔✔Dog house
✔✔Control houses contain equipment such as: - ✔✔1. Switchboard panels
2. Batteries
3. Battery chargers
4. Supervisory controls
5. Power line carrier
6. Meters
7. Relays
, ✔✔Why are DC Batteries kept in the control centers? - ✔✔To control equipment if
power is lost at the substation
✔✔The ground grid is a very critical element of the substation and is designed to
provide the following functions: - ✔✔1. Provide a path to ground for lighting
2. Provide a ground for all substation equipment
3. Ensure the safety of workers in the station by limiting the ground potential differences
4. Ensure the safety of the public
5. Provide a ground source for all lines coming in and out of the substation
✔✔The most common type of primary phase configuration is: - ✔✔WYE configuration
✔✔How many wires are in a WYE configuration? - ✔✔3 phases and a neutral (4 wires)
✔✔True / False: The neutral is grounded both at the substation and at every pole that
has a provided pole ground. - ✔✔True
✔✔Some of the most common distribution voltages are: - ✔✔2,400/4,160 volts
7,200/13,200 volts
12,000/20,800 volts
14,400/24,500 volts
19,900/34,500 volts
✔✔What number comes first? Phase to Phase or Phase to Ground? - ✔✔Phase to
Ground
✔✔What number comes second? Phase to Phase or Phase to Ground? - ✔✔Phase to
Phase
✔✔True / False: A Delta is older and less common. - ✔✔True
✔✔Is a Delta a 3 or 4 wire system? - ✔✔3 wire
✔✔Does a Delta system of a WYE system need help? - ✔✔Delta
✔✔Does a Delta system have a neutral? - ✔✔No
✔✔True / False: Transformers in a Delta system require 2 phases to their top bushing
while in a WYE system they only require 1. - ✔✔True
✔✔What are the two types of distribution layouts? - ✔✔Loop and Radial
✔✔What is more reliable? Loop or Radial? - ✔✔Loop
