LADWP Electrical Mechanic Test:
Key Formulas and Safety Procedures
Ammeter measurement and connection kind - ANS-Current; related in collection.
Approach boundary - ANS-Specified distance from exposed energized components requiring
PPE/education to pass.
Circuit breaker image on a one-line diagram - ANS-Break in line with arc or rectangle
representing breaker.
Direction of rotation for 2 meshed gears - ANS-Opposite instructions.
Formula for electrical energy in watts - ANS-P = V × I
Formula for power using resistance - ANS-P = I² × R or P = V² / R
Formula for three-segment electricity - ANS-P = √three × V_L × I_L × PF
Frequency of U.S. AC electricity - ANS-60 Hz
Line vs segment present day in a balanced three-segment Delta machine - ANS-I_L = √3 ×
I_phase
Line vs phase cutting-edge in a balanced 3-section Wye machine - ANS-I_L = I_phase
Line vs section voltage in a balanced 3-phase Wye system - ANS-V_L = √3 × V_phase
Lockout/Tagout (LOTO) - ANS-Safety manner to ensure system is de-energized earlier than
protection.
Mechanical gain formula for a lever - ANS-MA = Length of Effort Arm / Length of Load Arm
Minimum PPE for excessive-voltage work - ANS-Arc-rated clothing, voltage-rated gloves,
difficult hat, eye safety, listening to protection, insulated gear.
Ohm's Law - ANS-V = I × R — Voltage equals contemporary instances resistance.
PT vs CT in substations - ANS-PT reduces voltage for metering; CT reduces present day for
metering/safety.
Pulley gadget load in line with rope segment - ANS-Load weight ÷ number of rope sections
helping it.
Key Formulas and Safety Procedures
Ammeter measurement and connection kind - ANS-Current; related in collection.
Approach boundary - ANS-Specified distance from exposed energized components requiring
PPE/education to pass.
Circuit breaker image on a one-line diagram - ANS-Break in line with arc or rectangle
representing breaker.
Direction of rotation for 2 meshed gears - ANS-Opposite instructions.
Formula for electrical energy in watts - ANS-P = V × I
Formula for power using resistance - ANS-P = I² × R or P = V² / R
Formula for three-segment electricity - ANS-P = √three × V_L × I_L × PF
Frequency of U.S. AC electricity - ANS-60 Hz
Line vs segment present day in a balanced three-segment Delta machine - ANS-I_L = √3 ×
I_phase
Line vs phase cutting-edge in a balanced 3-section Wye machine - ANS-I_L = I_phase
Line vs section voltage in a balanced 3-phase Wye system - ANS-V_L = √3 × V_phase
Lockout/Tagout (LOTO) - ANS-Safety manner to ensure system is de-energized earlier than
protection.
Mechanical gain formula for a lever - ANS-MA = Length of Effort Arm / Length of Load Arm
Minimum PPE for excessive-voltage work - ANS-Arc-rated clothing, voltage-rated gloves,
difficult hat, eye safety, listening to protection, insulated gear.
Ohm's Law - ANS-V = I × R — Voltage equals contemporary instances resistance.
PT vs CT in substations - ANS-PT reduces voltage for metering; CT reduces present day for
metering/safety.
Pulley gadget load in line with rope segment - ANS-Load weight ÷ number of rope sections
helping it.
