114478128 Bently Nevada Mms

PROXIMITY TRANSDUCER SYSTEM OPERATION

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Copyright Bently Nevada Corporation All Rights Reserved, 1996 The following marks are Bently Nevada Corporation’s Registered Trade Trade Names:

MicroPROX  Keyphasor  Key   Trendmaster  Dynamic Data Manager 

ADRE  Proximitor  Velomitor  Smart Monitor  Transient Data Manager 

REBAM  Seismoprobe TorXimitor  Data Manager  Bently Nevada 

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Copyright Bently Nevada Corporation All Rights Reserved, 1996 The following marks are Bently Nevada Corporation’s Registered Trade Trade Names:

MicroPROX  Keyphasor  Key   Trendmaster  Dynamic Data Manager 

ADRE  Proximitor  Velomitor  Smart Monitor  Transient Data Manager 

REBAM  Seismoprobe TorXimitor  Data Manager  Bently Nevada 

TRIAXIAL CABLE CENTER CONDUCTOR

  OUTER SCREEN

INNER SCREEN

INSULATION

PROBE NUMBERING TIP ASSEMBLY CABLE

P/N 330106-05-30-10-02-00 S/N APRS 416567

FIXED LOCK NUT

EXTENSION CABLE NUMBERING

HEAT SHRINK SLEEVING

CONNECTOR

P/N 330130-080-00-00

PROXIMITOR

SIGNAL OUTPUT

TRANSDUCER POWER

SIGNAL COMMON

ELECTRICAL LENGTH

PROXIMITOR OPERATION <100mil

   Y   A    L   D    T   A    N    V    E   E    B   N

RF SIGNAL

EXTENSION CABLE AND PROBE

PROXIMITOR

DEMODULATOR OSCILLATOR

EDDY CURRENT FLOW

   R

CONDUCTIVE MATERIAL

   Y   A    L   D    T   A    V    N    E   E    B   N

RF SIGNAL

EDDY CURRENTS

SMALL GAP

RF SIGNAL

0

LARGE GAP

RF SIGNAL

0

CHANGING GAP

RF SIGNAL

0

DEMODULATOR OPERATION

DEMODULATOR 0 INPUT

PROXIMITOR OUTPUT

0

RADIAL AND AXIAL MOVEMENT

RADIAL MOVEMENT

AXIAL MOVEMENT

KEYPHASOR WITH NOTCH TARGET

NOTCH

GAP CHANGE

PROBE OVER SURFACE

TIME

ONE REVOLUTION VOLTAGE CHANGE

PROBE OVER NOTCH

KEYPHASOR WITH PROJECTION TARGET

N E  V  A D A

B E  N T  L  Y 

PROJECTION

GAP CHANGE

TIME ONE REVOLUTION

VOLTAGE CHANGE

PROBE OVER PROJECTION

PROBE OVER SURFACE

PROXIMITOR CALIBRATION GRAPH 24 22 CHANGE IN GAP

20    C    D      S    T    L    O    V    N    I    T    U    P    T    U    O

18 16    E    G    A    T    L    O    V    N    I

14 12 10

   E    G    N    A    H    C

8 6 4 2 0 mils

0

10

20 30

40

50

60

70

80 90 100 110 120 130 140

PROBE GAP

Average Scale Factor (ASF) equals: change in gap voltage change in gap

(-18.0Vdc) - (-2.0Vdc) 0.08in or 2.0 mm = 200 mV/mil

or = 7.87 mV/um

POWER SUPPLY VOLTAGE EFFECTS 24 22 20    C    D      S    T    L    O    V    N    I    T    U    P    T    U    O

-24V SUPPLY

18 16 14

-16V SUPPLY

12 10 8 6 4 2 0 mils

0

10

20

30

40

50

60

70

80

PROBE GAP

90

100 110 120 130 140

COMPONENT MISMATCH EFFECTS 24 22 20

SHORT    C    D      S    T    L    O    V    N    I    T    U    P    T    U    O

18

CORRECT

16 14 12 10 8 6

LONG

4 2 0 mils

0

10

20

30

40

50

60

70

80

PROBE GAP

90

100

110 120 130 140

TARGET MATERIAL EFFECTS 24 22 20    C    D      S    T    L    O    V    N    I    T    U    P    T    U    O

18 16 14 12 10 8 4140 STEEL

6

TUNGSTEN ALUMINUM

4

COPPER

2 0 mils 0

10

20

30

40

50

60

70

80

PROBE GAP

90

100 110 120 130 140

CROSSTALK

SIDEVIEW

TARGET SIZE

 YES

NO

PROXIMITOR CALIBRATION EQUIPMENT SET-UP

PROXIMITOR CALIBRATION EQUIPMENT SET-UP PROBE TARGET

SPINDLE MICROMETER

EXTENSION CABLE PROXIMITOR

N E  V  A  D A 

DC VOLTMETER

B  E  N T  L  Y 

 o  u  t    c   o m v   t  

-VT INPUT

APPLICATION EXERCISE Q1. The three parts of a proximity transducer system are: a. Probe b. Extension cable c. Proximitor Q2. The ruggedised coaxial cable used in the system has a center conductor two screens . Q3. What is the electrical length of the following probe? 330106-05-30-05-020.5M . Q4. What is the electrical length of the following extension cable? 330130-045-00-00 4.5M . Q5. What is the total electrical length required by the following Proximitor? 330100-50-00 5.0M .

APPLICATION EXERCISE -17.5 Vdc Q6. The Proximitor must be supplied with a dc voltage between -26.0 Vdc  ____________ and . RF Q7. An field is created around the80 probe. mils It extends away from the face of the probe for linear range of at least . eddy currents Q8. When a conductive material is within range of the probe _____________ flow in the surface of that material. material Q9. A Proximitor must be calibrated to suit the

it has as a target. positive

Q10. The dc output from the Proximitor will go more 0Hz(dc) moves closer to the probe. ac dc Q11. A proximity system frequency response is from and

as the target 10KHz to

APPLICATION EXERCISE Q12. Name three applications for a proximity transducer system. a. Thrust measurement b. Vibration measurement Keyphasor c. _____________________ Q13. Calculate the scale factor (sf) from the following: 90mils = 18.5Vdc, 10mils = 2.25Vdc. 203mV/mil Is it within tolerance? Yes, 1.5% error Q14. Name three reasons why a proximity system could be out of tolerance. a. Incorrect supply voltage b. Mismatched components c. Incorrect target material