Filters
This filter allows low frequencies to pass while blocking high frequencies.
What is a low-pass filter?
Power factor is the ratio of this type of power to apparent power.
What is true power?
To find phase voltage in a wye system, divide the line voltage by this number.
What is 1.732 (√3)?
The primary function of a transformer is to perform this task.
What is step up or step down voltage?
This instrument measures current without opening the circuit.
What is a clamp-on ammeter?
This filter allows high-frequency signals to pass while blocking low-frequency signals.
What is a high-pass filter?
A power factor of 1.0 means all supplied power is converted into this.
What is useful work (real power)?
In a delta system, line voltage has this relationship to phase voltage.
What is line voltage equals phase voltage?
The voltage ratio of a transformer depends on this.
What is the number of turns in the primary and secondary windings?
This instrument measures voltage, current, and resistance in one device.
What is a multimeter?
This filter is commonly used in audio applications to isolate mid-range frequencies.
What is a band-pass filter?
This type of load usually causes a lagging power factor.
What is an inductive load?
This type of three-phase connection provides both line-to-line and line-to-neutral voltages.
What is a wye connection?
When connecting transformers in parallel, this value must be the same.
What is percent impedance (%Z)?
This instrument checks for voltage without making direct contact with a live conductor.
What is a voltage indicator?
This filter blocks a narrow range of frequencies while allowing most others to pass.
What is a band-reject filter?
This component is commonly installed in parallel with an inductive load to improve power factor.
What is a capacitor?
Industrial facilities often use this connection because it does not require a neutral conductor.
What is a delta connection?
Compared to single-phase motors, this type of motor operates more smoothly and efficiently.
What is a three-phase motor?
This instrument is used to test the insulation resistance of motors and cables.
What is a megohmmeter?
This point on a filter's response curve is the frequency at which the load receives 50% of its maximum power.
What is the half-power point?
Power factor is usually corrected to about 90–95% to avoid this condition.
What is a leading power factor (overcorrection)?
In a 4-wire delta system, this conductor has a voltage to ground equal to 1.732 times the phase voltage.
What is the high leg (wild leg)?
A motor experiencing single-phasing will most likely exhibit this symptom.
What is overheating and possible stalling under load?
Before connecting an in-line ammeter, this must be done first.
What is de-energize the circuit?