Claims
- 1. A machinery vibration monitoring apparatus, comprising:
- a transducer responsive to vibration in machinery operative to produce an electrical transducer signal functionally related to the magnitude and frequency of said vibration;
- a decoding circuit responsive to said electrical transducer signal greater than a predetermined magnitude within a selected frequency band to produce a first fault signal after a predetermined approximate number of cycles have occurred of said electrical transducer signal within said frequency band; and
- isolating circuitry responsive to said first fault signal to produce a second fault signal in which ground shift effects are nullified.
- 2. The apparatus of claim 1, wherein:
- said isolating circuitry includes optical isolation circuitry.
- 3. The apparatus of claim 1, further comprising:
- a means for adjusting the width of said frequency band.
- 4. The apparatus of claim 1, further comprising:
- a means for adjusting said predetermined approximate number of cycles of said electrical transducer signal within said frequency band.
Parent Case Info
This is a division of application Ser. No. 07/834,451, filed Feb. 12, 1992 now U.S. Pat. No. 5,309,149.
US Referenced Citations (7)
Divisions (1)
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Number |
Date |
Country |
Parent |
834451 |
Feb 1992 |
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