Keyphasor Phase Reference Sensor

A signal used in rotating machine measurements, generated by a sensor observing a once-per-revolution event. (Keyphasor is a Bently-Nevada trade name.)

Key

A metallic mating load-transmitting member placed in a groove in both the shaft and hub.

Keyseat (Shaft keyway)

The axial groove in the shaft that holds the key in the proper location.

Keyway

The axial groove in the hub that holds the key in the proper 1ocation.

Keying Frequency

1. In audio-keyed radiotelegraphy, the audio frequency (tone) of the dot and dash signals (as opposed to the carrier frequency). 2. In radiotelegraphy, the transmission speed (see KEYING SPEED). 3. The number of times per second that a black-line signal occurs while an object is scanned in a facsimile system.

Kelvin Absolute Electrometer

An electrostatic voltmeter consisting of a movable metal plate (or plates) and a stationary metal plate (or plates)between which voltage is applied. The movable plate(s) is displaced over a distance that is proportional to the potential, against the torque of a return spring.