REED R7900 User manual

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Ultrasonic Thickness Gauge
Instruction Manual
Pantone 534 Blue
Pantone 123 Yellow
Pantone 485 Red
Pantone 123 Yellow
Pantone 534 Blue
Black Rich Black -
20/20/20/100
Blue - 100/80/30/5
Yellow - 0/27/100/0
Red - 10/100/100/5
Yellow - 0/27/100/0
Blue - 100/80/30/5
Only if you REALLY need them:
Pantone 534 Blue - 100/80/30/5
Pantone 485 Red - 10/100/100/5
Pantone 123 Yellow - 0/27/100/
INSTRUMENTS
Model R7900

reedinstruments
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2
Pantone 534 Blue
Pantone 123 Yellow
Pantone 485 Red
Pantone 123 Yellow
Pantone 534 Blue
Black Rich Black -
20/20/20/100
Blue - 100/80/30/5
Yellow - 0/27/100/0
Red - 10/100/100/5
Yellow - 0/27/100/0
Blue - 100/80/30/5
Only if you REALLY need them:
Pantone 534 Blue - 100/80/30/5
Pantone 485 Red - 10/100/100/5
Pantone 123 Yellow - 0/27/100/
INSTRUMENTS
Table of Contents
Features......................................................................................... 3
Specications.............................................................................4-5
Instrument Description .................................................................. 6
Operating Instructions..............................................................7-10
Adjusting the Sound Velocity....................................................... 7
Setting Probe Frequency ............................................................ 7
Preparing the Measurement Surface ........................................... 7
Taking Thickness Measurements................................................. 8
Zero Calibration .......................................................................... 8
Sound Velocity Measurements.................................................... 9
Setting Alarm Thickness Limits.................................................... 9
Minimum Capture Measurements ............................................. 10
Two Point Calibration ................................................................ 10
Measurement Methods ..........................................................11-13
Measurements on Cylindrical Surfaces...................................... 11
Measuring Compound Profiles .................................................. 12
Measuring an Un-Parallel Surface ............................................. 12
Influence of Material’s Temperature ........................................... 12
Material with Large Attenuation ................................................. 12
Measuring Castings .................................................................. 13
Preventing Errors....................................................................14-16
Reference Test Pieces............................................................... 14
Ultra-thin Material...................................................................... 15
Rust, Corrosion, and Pits .......................................................... 15
Error in Identifying Material ........................................................ 15
Degradation of Probe................................................................ 15
Overlapped Material and Compound Material ........................... 15
Influence of Metal Surface Oxidation ......................................... 16
Abnormal Readout of Thickness................................................ 16
Utilization and Selection of a Coupling Agent............................. 16
continued ...

reedinstruments
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3
Pantone 534 Blue
Pantone 123 Yellow
Pantone 485 Red
Pantone 123 Yellow
Pantone 534 Blue
Black Rich Black -
20/20/20/100
Blue - 100/80/30/5
Yellow - 0/27/100/0
Red - 10/100/100/5
Yellow - 0/27/100/0
Blue - 100/80/30/5
Only if you REALLY need them:
Pantone 534 Blue - 100/80/30/5
Pantone 485 Red - 10/100/100/5
Pantone 123 Yellow - 0/27/100/
INSTRUMENTS
Menu Options.........................................................................17-18
System Setup ........................................................................... 17
Print Function............................................................................ 18
Memory Manager ..................................................................... 18
Restore Factory Defaults........................................................... 18
Internal Memory Operation ......................................................... 19
Reviewing Stored Data.............................................................. 19
Maintenance...........................................................................19-20
Cleaning the Test Piece............................................................. 19
Protecting the Probe................................................................. 19
Changing the Probe.................................................................. 20
Battery Replacement................................................................... 20
Features
• Capable of performing measurements on a wide range of material
including metals, plastic, ceramics, composites, epoxies, glass, and
other ultrasonic conductive materials
• Zero function and Sound Velocity Calibration
• Two-Point Calibration
• Coupling status indicator
• Auto sleep and auto power off function to conserve battery life
• Applications include monitoring various pipes and pressure vessels
in production equipment, monitor the thinning degree during use
• For use in petroleum, chemical, metallurgy, shipping, aerospace,
aviation, and other elds

reedinstruments
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4
Pantone 534 Blue
Pantone 123 Yellow
Pantone 485 Red
Pantone 123 Yellow
Pantone 534 Blue
Black Rich Black -
20/20/20/100
Blue - 100/80/30/5
Yellow - 0/27/100/0
Red - 10/100/100/5
Yellow - 0/27/100/0
Blue - 100/80/30/5
Only if you REALLY need them:
Pantone 534 Blue - 100/80/30/5
Pantone 485 Red - 10/100/100/5
Pantone 123 Yellow - 0/27/100/
INSTRUMENTS
Specifications
Display: 128 x 64 LCD with LED backlight
Measurement Range: 0.65 to 400.0mm (0.03 to 15.7”),
dependant on materials and conditions
Sound Velocity Range: 1000 to 9999m/s (0.039 to 0.394in/µs)
Display Resolution: High: 0.01mm or 0.1mm (lower than 100.0mm)
Low: 0.1mm (more than 99.99mm)
Accuracy: ±0.04mm (lower than 10mm)
±(0.1% thickness + 0.04)mm (lower than 100mm)
±(0.3% thickness)mm (more than 100mm)
Units: Metric and Imperial, user selectable
Lower Limit for Steel Pipes:
5MHz probe: Ø20mm×3.0mm (Ø0.8× 0.12 inch)
7MHz probe: Ø15mm×2.0mm (Ø0.6× 0.08 inch)
Measurement Speed: 4 per second for a single point measurement
Memory: 5 les, up to 100 values for each le
(total of 500 logs)
Communication: RS-232 Serial Port (Optional)
Power Supply: 2 x 1.5V AA Batteries
Operating Time: 100 hours typical, with LED backlight off
Dimensions: 150 x 74 x 32mm
Weight: 238g
Includes: Transducer, couplant, 2 x 1.5V battery,
and carrying case
Probe Specifications
Frequency: 5MHz
Range: 1.2 to 300.0mm (steel)
Minimum Area: ø20×3mm
Applications: General Straight Probe

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5
Pantone 534 Blue
Pantone 123 Yellow
Pantone 485 Red
Pantone 123 Yellow
Pantone 534 Blue
Black Rich Black -
20/20/20/100
Blue - 100/80/30/5
Yellow - 0/27/100/0
Red - 10/100/100/5
Yellow - 0/27/100/0
Blue - 100/80/30/5
Only if you REALLY need them:
Pantone 534 Blue - 100/80/30/5
Pantone 485 Red - 10/100/100/5
Pantone 123 Yellow - 0/27/100/
INSTRUMENTS
Sound Velocity for Different Materials
Material Sound velocity
(m/s) (inch/µs)
Aluminum 6320 to 6400 0.250
Zinc 4170 0.164
Silver 3607 0.142
Gold 3251 0.128
Tin 2960 0.117
Steel, Common 5920 0.233
Steel, Stainless 5740 0.226
Brass 4399 0.173
Copper 4720 0.186
Iron 5930 0.233
Case Iron 4400 to 5820 0.173 to 0.229
Lead 2400 0.094
Nylon 2680 0.105
Titanium 5990 0.236
SUS 5970 0.240
Epoxy Resin 2540 0.100
Ice 3988 0.222
Plexiglass 2692 0.106
Grey Cast 4600 0.180
Porcelain 5842 0.230
Glass (Quartz) 5570 0.220
Polystyrene 2337 0.092
PVC 2388 0.094
Quartz Glass 5639 0.222
Rubber, Vulcanized 2311 0.091
Teon 1422 0.058
Water 1473 0.058

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6
Pantone 534 Blue
Pantone 123 Yellow
Pantone 485 Red
Pantone 123 Yellow
Pantone 534 Blue
Black Rich Black -
20/20/20/100
Blue - 100/80/30/5
Yellow - 0/27/100/0
Red - 10/100/100/5
Yellow - 0/27/100/0
Blue - 100/80/30/5
Only if you REALLY need them:
Pantone 534 Blue - 100/80/30/5
Pantone 485 Red - 10/100/100/5
Pantone 123 Yellow - 0/27/100/
INSTRUMENTS
Instrument Description
1. Probe Socket
2. RS-232 Socket
3. Probe
4. Test piece
Keypad Description
1. Velocity Button
2. Save/Browse Data
3. Power On/Off Button
4. Zero Button
5. Up Button
6. Backlight On/Off Button
7. Mode Button
8. Down Button
9. Enter Button
Display Description
1. Coupling Indicator
2. Gain Indicator
3. Minimum Capture Mode
4. Battery Indicator
5. Main Display Area
6. Alarm Thickness Limit
7. Probe Frequency
8. Save File Name
9. Menu Option

reedinstruments
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7
Pantone 534 Blue
Pantone 123 Yellow
Pantone 485 Red
Pantone 123 Yellow
Pantone 534 Blue
Black Rich Black -
20/20/20/100
Blue - 100/80/30/5
Yellow - 0/27/100/0
Red - 10/100/100/5
Yellow - 0/27/100/0
Blue - 100/80/30/5
Only if you REALLY need them:
Pantone 534 Blue - 100/80/30/5
Pantone 485 Red - 10/100/100/5
Pantone 123 Yellow - 0/27/100/
INSTRUMENTS
Operating Instructions
1. Insert the probe into the probe socket on the meter
2. Press the Power Button to turn the meter on
3. The LCD will briey display information about the meter, and then
show the current set sound velocity
Adjusting the Sound Velocity
This instrument can display ve sound velocities alternatively.
1. Press the Velocity Button and the meter will display the current
sound velocity
2. Press the Velocity Button to switch between the 5 set velocities,
and press the Up and Down Buttons to adjust the set value
Setting Probe Frequency
1. Press the Mode Button to highlight the Probe Frequency setting
on the LCD
2. Press the Enter Button to change the frequency setting between
5M, 7M, and ZW probe frequencies
Preparing the Measurement Surface
• Clean any dust, dirt, and rust off the object, and remove any cover
such as paint.
• Smooth the surface of the object by grinding or polishing it. You
can also use a coupling agent with a high viscosity.
• If the surface has a rough machined surface and cannot be
smoothed down, adjust the angle between the probe’s crosstalk
interlayer plate (the metallic layer passing through the centre of
probe bottom) and the ne slots of the object that the interlayer
plate is perpendicular or parallel to. Take the minimum value of the
readouts as the measured thickness.

reedinstruments
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8
Pantone 534 Blue
Pantone 123 Yellow
Pantone 485 Red
Pantone 123 Yellow
Pantone 534 Blue
Black Rich Black -
20/20/20/100
Blue - 100/80/30/5
Yellow - 0/27/100/0
Red - 10/100/100/5
Yellow - 0/27/100/0
Blue - 100/80/30/5
Only if you REALLY need them:
Pantone 534 Blue - 100/80/30/5
Pantone 485 Red - 10/100/100/5
Pantone 123 Yellow - 0/27/100/
INSTRUMENTS
Taking Thickness Measurements
1. Set the Sound Velocity on the meter
2. Coat the piece to be measured with coupling agent
3. Place the probe on the area and the Coupling Indicator will appear
on the LCD
4. Read the measurement on the LCD
5. When you remove the probe the value will stay on the LCD and
the Coupling Indicator will disappear
6. Press the Save Button to save the measurement
If the Coupling Indicator ashes or doesn’t appear it means that the
coupling is not good.
Zero Calibration
1. Select the correct frequency for the probe in use
2. Set the Sound Velocity to 5900m/s
3. Select the proper Receiving Gain (see System Setup)
4. Coat the 4mm Standard Test Block with Coupling Agent and press
the probe to the Test Block
5. If the Coupling Indicator is showing on the LCD then press the
Zero Button to initiate Zero Calibration
6. The meter will beep and then the screen will indicate that the
calibration is complete
7. If Zero Calibration is not properly completed the meter will retain
the original value
8. To delete the calibration data, see Memory Manager

reedinstruments
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9
Pantone 534 Blue
Pantone 123 Yellow
Pantone 485 Red
Pantone 123 Yellow
Pantone 534 Blue
Black Rich Black -
20/20/20/100
Blue - 100/80/30/5
Yellow - 0/27/100/0
Red - 10/100/100/5
Yellow - 0/27/100/0
Blue - 100/80/30/5
Only if you REALLY need them:
Pantone 534 Blue - 100/80/30/5
Pantone 485 Red - 10/100/100/5
Pantone 123 Yellow - 0/27/100/
INSTRUMENTS
Sound Velocity Measurements
The sound velocity of a material can be measured using a test piece with
known thickness. Select a test piece with a minimum wall thickness of
20.0mm. Turn off the minimum capturing function prior to taking
measurement.
1. Measure the test piece with a calliper or micrometer
2. Measure the test piece with the probe until it displays a value and
remove the probe
3. Adjust the display to the actual thickness with the Up or Down
Buttons and press the Velocity Button
4. The LCD will display the Sound Velocity
5. Press the Save Button to save the value
Setting Alarm Thickness Limits
This meter will alarm if the thickness measurement is out of the pre-set
limits. When the measurement is lower than the low limit or higher than
the high limit, the alarm will sound.
1. Press the Mode Button to highlight the Alarm setting on the LCD
2. Press the Enter Button to adjust the Low Limit
3. Press the Up and Down Buttons to adjust the Low Setting
4. Press the Enter Button to save the Low Setting, and to set the
High Setting
5. Press the Up and Down buttons to adjust the High Setting, and
press the Enter Button to save the setting

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Pantone 534 Blue
Pantone 123 Yellow
Pantone 485 Red
Pantone 123 Yellow
Pantone 534 Blue
Black Rich Black -
20/20/20/100
Blue - 100/80/30/5
Yellow - 0/27/100/0
Red - 10/100/100/5
Yellow - 0/27/100/0
Blue - 100/80/30/5
Only if you REALLY need them:
Pantone 534 Blue - 100/80/30/5
Pantone 485 Red - 10/100/100/5
Pantone 123 Yellow - 0/27/100/
INSTRUMENTS
Minimum Capture Measurements
When the probe couples with the work piece it will display the current
measurement. When the probe is lifted away it will display the minimum
value of the measurement carried out while the MIN Indicator ashes for
several seconds. If you continue taking measurements while the MIN
Indicator is ashing, the former measurements will continue to take part
in the minimum value capturing. If you carry out measurements after the
MIN Indicator stops ashing the minimum value capturing will re-start.
When the Minimum capture function is ON the LCD will display the MIN
Indicator.
Two Point Calibration
1. Select two standard samples of the same material to be
measured, among which one has a thickness equal to or slightly
higher than the tested piece, and the thickness of another test
piece is slightly lower than the tested piece
2. Before carrying out 2-point calibration, turn off the Minimum
Capture Function and Erase the CAL Data in the Memory Manager
3. Set the 2-point calibration to ON in the System Setup Menu
4. Press the Mode Button to return to the main display
5. Press the Enter Button at any time during measurement to enter
the 2-Point CAL
6. Measure the thinner standard test piece and use the Up and Down
Buttons to adjust the measurement to standard value
7. Press the Enter Button and the LCD will prompt to measure the
thicker piece
8. Measure the thicker standard test piece and use the Up and Down
Buttons to adjust the measurement to standard value
9. Press the Enter Button when the calibration operation is nished