The keyphasor is an electrical pulse, or trigger, derived from a rotating shaft point. It serves as a reference for zero phase to determine where a rotor has an imbalance.
A keyphasor signal is a one-time or multi-event-per-turn pulse from a rotating shaft or gear used for accurate timing measurement. In the measurement of rotor slow roll bow or runout information, it is an essential element.
Typically, the Keyphasor transducer is a proximity probe (recommended for permanent installations where the probe observes a physical gap change event), an optical pickup (used for temporary installations where the pickup observes a reflectivity change event) or a magnetic pickup.
Working of Keyphasor:
Keyphasor is an electrical pulse, or trigger, derived from a point on a rotating shaft, which acts as a zero - phase reference to determine where a rotor is imbalanced. At the time of dynamic balancing, the keyphasor in turbo machines is needed to find phase angle of unbalance mass.
The keyphasor shows machine health with vibration probes alone, but if you want to analyze the machine’s cause of failure you need a three-dimensional graph showing / analyzing the vibrations at any time when the machine runs.
If you don’t install the keyphasor, you’ll find out there are vibrations in the machine, but you won’t point at what direction, at what point, at what angle.
The Keyphasor signal is used to generate filtered vibration by monitoring, diagnosis, and management systems. Amplitude, lag in phase, speed and other useful information variety. Phase is a critical piece of this information.
Overall machine condition and machine failures would often be very difficult without phase information.
The Keyphasor signal is used by monitoring, diagnosis, and management systems to generate filtered vibration. Amplitude, phase lag, velocity and other useful variety of information. Phase is a key piece of this information. Overall machine condition and failures without phase information would often be very difficult.
At the time of dynamic balancing, keyphasers in turbomachines are required to find phase angle of unbalance mass. It is essential to balance the turbine rotor.