OPERATION MANUAL DAKOTA ULTRASONICS PVX Precision A / B Scan Thickness Gauge P/N P-157-0002 Rev 1.
Dakota Ultrasonics
CHAPTER ONE INTRODUCTION .......................................................................1 CHAPTER TWO QUICK STARTUP GUIDE ........................................................2 CHAPTER THREE KEYBOARD, MENU, & CONNECTOR REFERENCE.......12 CHAPTER FOUR PRINCIPALS OF ULTRASONIC MEASUREMENT .............22 CHAPTER FIVE SELECTING THE MEASUREMENT MODE ..........................27 CHAPTER SIX MAKING MEASUREMENTS.....................................................
CHAPTER ONE INTRODUCTION The Dakota Ultrasonics model PVX is a visual precision A / B scan ultrasonic thickness gauge. Based on the same operating principles as SONAR, the PVX is capable of measuring the thickness of various materials with accuracy as high as ± 0.0001 inches, or ± 0.001 millimeters. The principle advantage of ultrasonic measurement over traditional methods is that ultrasonic measurements can be performed with access to only one side of the material being measured.
Dakota Ultrasonics CHAPTER TWO QUICK STARTUP GUIDE Turn the PVX on and off using the switch located on the bottom right corner of the keypad. When PVX is initially turned on, a flash logo and blinking lights will be displayed prior to entering into the main measurement screen. Note: This section is primarily written as a basic startup guide only. 2.1 Selecting The Transducer Type The first step in using the PVX is to select the transducer type stored in a setup.
PVX Precision Visual Thickness Gauge 3) Press the ENTER key to display the confirmation screen. 4) Press the OK key to select the setup and return to the measure screen, or ESC to cancel the selecting a setup. 2.2 Calibration The next step is to calibrate the PVX to the material and transducer being used. If a sound velocity is not known, the PVX can be calibrated to a known thickness sample. This demo will briefly explain each of possible calibration techniques.
Dakota Ultrasonics 2) Use the UP and DOWN arrow keys to scroll through the sub menu items until VELOCITY is highlighted. 3) Press the ENTER key to display the Digits Edit Box. 4) Press the UP and DOWN arrow keys to scroll the highlighted value. 5) Press the LEFT and RIGHT arrow keys to scroll the digit locations. 6) Repeat steps 4 & 5 until the velocity number is correctly displayed. 7) Press the OK key to set the velocity and return to the menu screen, or ESC to cancel entering the velocity.
PVX Precision Visual Thickness Gauge 1) Physically measure an exact sample of the material or a location directly on the material to be measured using a set of calipers or a digital micrometer. 2) Apply a drop of couplant on the transducer and place the transducer in steady contact with the sample or actual test material. Be sure that the reading is stable and the repeatability indicator, in the top left corner of the display, is fully lit and stable. Press the MENU key once to activate the menu items tab.
Dakota Ultrasonics 8) Press the OK key to calculate the velocity and return to the menu screen, or ESC to cancel entering the velocity. 9) Finally, press the MEAS key to return to the measurement screen and begin taking readings. Note: CHECK YOUR CALIBRATION! Place the transducer back on the calibration point. The thickness reading should now match the known thickness. If the thickness is not correct, repeat the steps above.
PVX Precision Visual Thickness Gauge Basic Material Type If the material velocity is unknown, and a sample thickness cannot be taken from the material, the user may opt to choose a basic material type from a list with approximate velocity numbers. It’s important to note that these velocities will not always be an exact representation of the material being tested. Use these values only if a close approximation is acceptable.
Dakota Ultrasonics 2.3 Measure The PVX is now ready to measure. There are four different measurement view options, each with a specific purpose. The steps below outline how to toggle between the different view mode options: Selecting the Measurement View Option 1) Press the MENU key once to activate the menu items tab. Press the MENU key multiple times to tab right and the ESC key multiple times to tab left until the DISP menu is highlighted and displaying the submenu items.
PVX Precision Visual Thickness Gauge BSCAN: The Time Based B-Scan provides the user with a cross sectional view of the material being tested. This mode is useful when there is concern regarding the profile of the blind surface. DIGITS: Displays the digital thickness value using a larger font size. This view is useful when the PVX is being used as a basic precision thickness gauge following the initial setup using the scope.
Dakota Ultrasonics 1) Press the MEAS key once to activate measure menu items. Press the MEAS key multiple times to move right and the ESC key multiple times to move left, until the either the DELAY or WIDTH cell is highlighted. 2) Press the ENTER key to display the digits edit box. 3) Press the UP and DOWN arrow keys to scroll the highlighted value. 4) Press the LEFT and RIGHT arrow keys to scroll the digit locations. 5) Repeat steps 3 & 4 until the DELAY or WIDTH value is correctly displayed.
PVX Precision Visual Thickness Gauge B-SCAN DIGITS In the upper left corner of each of the mode photos above, is the repeatability indicator. The repeatability indicator is represented by six vertical bars and represents how repeatable the measurements are. In regular measurement mode, the PVX makes 4 measurements a second. In scan mode, the PVX makes 32 measurements a second. When the PVX is idle, only the left vertical bar and the underline will be displayed.
CHAPTER THREE KEYBOARD, MENU, & CONNECTOR REFERENCE 3.1 Menu Key (Operation & Sub Menus ) The Menu key activates the primary menu structure containing 9 menu tab groups. These tab groups then contain sub menu items, or functions. The sub menu items have been organized in tab groups according to how closely they are related to the individual tab group names. Let’s first get familiar with how to move around in these tabs before continuing on to the sub menu functions.
PVX Precision Visual Thickness Gauge 1) Press the MENU key once to activate the menu items tab. Press the MENU key multiple times to tab right, and the ESC key multiple times to tab left until the desired tab group is highlighted and displaying the submenu items.
Dakota Ultrasonics on. The options are Spike, Thin , and Wide. Refer to page 71 for a further explanation. 3.3 CAL – Menu Units: Toggle between English or Metric units and low and hi resolutions. The readout will change from inches to millimeters (IN, IN HR, MM, MM HR). The high resolution options are indicated with HR following the units, and offer an additional decimal place of overall resolution (i.e. IN = .001” and IN HR = .0001”).
PVX Precision Visual Thickness Gauge 3.5 TUNE – Menu Gain: Increases or decreases the overall amplitude of the signal. Much like turning the volume up or down on a stereo receiver. Refer to page 55 for further info. AGC: The PVX is equipped with an automatic gain control when operating in interface-echo a nd echo-echo modes only. This is much like turning the volume up or down on a stereo receiver. However, the PVX will automatically control how much the volume is turned up or down.
Dakota Ultrasonics 3.7 SETUP – Menu Open: Displays a list of factory and user defined setups currently stored in memory. These setups can be recalled and used at any time. Refer to page 99 for further info. Save: Provides the user with the ability to save a custom setup that has been modified or created by the user. Refer to page 101 for further info. Default Setup: Loads a basic default setup. Use only as a last resort when the setups in the PVX have been corrupted and a computer is not accessible.
PVX Precision Visual Thickness Gauge Auto Find: Automatically locates the detection point if the measurement is out of the viewable display area. Refer to page 72 for further info. Scan Mode: This function enables a hi speed scan mode that increases the overall sample rate from the standard 4 measurements a second to 32 measurements a second. Refer to page 73 for further info. Alarm Status: Toggles alarm mode on or off. Refer to page 74 for further info.
Dakota Ultrasonics saved a measurement and waveform to a cell location, use this key to clear the measurement at any time. 3.12 MEAS (measurement mode) Key The MEAS key puts the PVX into it’s primary mode of operation. In this mode, the user has a complete view of the LCD, as well as control of the Hot Menu Functions.
PVX Precision Visual Thickness Gauge Alternatively , the delay, width, gain, and threshold hot function fields can be changed using the Digit Edit Box as follows: 1) Press the ENTER key to display the Digits Edit Box. 2) Press the UP and DOWN arrow keys to scroll the highlighted value. 3) Press the LEFT and RIGHT arrow keys to scroll the digit locations. 4) Repeat steps 2 & 3 until the delay, width, gain, or threshold number is correctly displayed.
Dakota Ultrasonics 3.16 ENTER key The ENTER key is used in the overall menu selection process, to activate list and edit boxes, and save measurements to grid locations. 3.17 MULTI MODE Key The MULTI MODE key activates the Load Setup List to select a factory or previously saved user setup for a variety of different transducer types and scope settings. This is a quick and efficient way to change modes and transducer types without having to manually adjust PVX.
PVX Precision Visual Thickness Gauge Probe Zero Disk & Battery Cover Refer to Diagram: The Battery cover is the large round disk shown in the diagram. Note: This same disk is also used as a probe zero disk. Simply remove the cover when replacing the batteries (3 AA cells). When performing a probe zero function, simply place the transducer on the disk making firm contact. Important: Be sure to follow the polarity labels located on the back label of the PVX.
CHAPTER FOUR PRINCIPALS OF ULTRASONIC MEASUREMENT 4.1 Time versus thickness relationship Ultrasonic thickness measurements depend on measuring the length of time it takes for sound to travel through the material being tested. The ratio of the thickness versus the time is known as the sound velocity. In order to make accurate measurements, a sound velocity must be determined and entered into the instrument. The accuracy of a thickness measurement therefore depends on having a consistent sound velocity.
PVX Precision Visual Thickness Gauge through air efficiently. By using a liquid couplant between the transducer and test piece the amount of ultrasound entering the test piece is much greater. 4.5 Temperature Temperature has an effect on sound velocity. The higher the temperature, the slower sound travels in a material. High temperatures can also damage transducers and present a problem for various liquid couplants.
Dakota Ultrasonics echoes are needed which requires a much stronger echo (reflection). In interfaceecho mode, it moves the interface further out in time eliminating any noise that’s close to the initial pulse. Important: The primary difference between interface-echo and echo -echo mode, is interface-echo mode measures from the end of an interface (delay line), to the first return reflection of the test material. However, in echo -mode, the measurement is made between two return reflections (echoes).
PVX Precision Visual Thickness Gauge Diagram 2 Refer to diagram 2. Referring to (Idle), you’ll notice that when the PVX is in interface-echo mode a waveform from the end of the delay line will always be displayed and active on the screen when idle (A). Since the gates are also used in interface-echo mode, they will be displayed (B). When measuring, two detects will be displayed between two waveforms at (C) & (F).
Dakota Ultrasonics Refer to diagram 3. The above diagram illustrates a typical view of echo-echo mode using a delay line style transducer. The end of the interface or delay line is displayed at (B). However, unlike interface echo mode the measurement is occurring between two return reflections (A) and (B). Recall that in interface echo mode, the measurements occurred between the interface (B) and the first return reflection (A). This is the primary difference between the two modes.
CHAPTER FIVE SELECTING THE MEASUREMENT MODE 5.1 The setup library The PVX contains 16 factory setups and 48 user definable preset locations to store custom setups for easy recall. These setups can be optimized for the user’s specific application needs and can also be stored on a PC and transferred bi-directionally using Dakota’s PC interface software included with the instrument.
Dakota Ultrasonics Plastics The PVX works extremely well on thin plastics using a delay line transducer and special graphite tip. Because the velocity of the standard acrylic tip has a similar velocity to most plastics, the PVX is unable to measure the material because it simply can't see it. By using the graphite tip in place of the acrylic tip, the velocity of the graphite tip allows an impedance mismatch to occur between materials, hence the plastic can successfully be measured.
PVX Precision Visual Thickness Gauge 5.3 Factory Setup Chart Num Name 1 2 Comment 1 Gn/AGC Velocity E-E DELAY LINE 3/8 I-E DELAY LINE 3/8 3 3 0.2330 in/uSec 0.2330 in/uSec 3 E-E DELAY LINE 1/2 3 0.2330 in/uSec 4 I-E DELAY LINE 1/2 3 0.2510 in/uSec 5 6 E-E GRAPHITE STEEL I-E GRAPHITE STEEL 3 3 0.0940 in/uSec 0.0940 in/uSec 7 I-E GRAPHITE PLASTIC 3 0.0920 in/uSec 8 E-E PENCIL PTR-100E 3 0.2330 in/uSec 9 10 I-E PENCIL PTR-100E E-E PENCIL PTR-300E 3 6 0.2330 in/uSec 0.
CHAPTER SIX MAKING MEASUREMENTS The steps involved in making measurements are detailed in this section. The following sections outline how to setup and prepare your PVX for field use. In pulse-echo modes, the probe zero must be measured on the reference disk (battery disk) attached to the top of the instrument. This compensates for variation in the transducer. In all modes the sound velocity must be determined. The sound velocity is used to convert the transit time to a physical length.
PVX Precision Visual Thickness Gauge 1) Press the MULTI MODE key once to activate the load setup list containing the transducer types and settings. 2) Use the UP and DOWN arrow keys to scroll through the setup list until the target setup is highlighted. 3) Press the ENTER key to display the confirmation screen. 4) Press the OK key to select the setup and return to the measure screen, or ESC to cancel the selecting a setup.
Dakota Ultrasonics 1) Alternately, the setups can be selected from the menu items. However, this is not as efficient. Press the MENU key once to activate the menu items tab. Press the MENU key multiple times to tab right and the ESC key multiple times to tab left until the SETUP menu is highlighted and displaying the submenu items. 2) Use the UP and DOWN arrow keys to scroll through the sub menu items until OPEN is highlighted. 3) Press the ENTER key to display the list of stored setups.
PVX Precision Visual Thickness Gauge Selecting the Measure Mode Using The Tabbed Submenu Items Note: The E-E mode should also be selected for setting up the PVX in I-E mode. 1) Press the MENU key once to activate the menu items tab. Press the MENU key multiple times to tab right and the ESC key multiple times to tab left until the GATE menu is highlighted and displaying the submenu items. 2) Use the UP and DOWN arrow keys to scroll through the sub menu items until MEASURE MODE is highlighted.
Dakota Ultrasonics Performing a Probe Zero 1) Clean the surface of the Probe Zero Disk, located on top of the PVX (battery cover). 2) Apply a drop of couplant to the end of the transducer, or probe disk, and hold the transducer in steady contact with the reference disk. 3) Press the MENU key once to activate the menu items tab. Press the MENU key multiple times to tab right and the ESC key multiple times to tab left until the PROBE menu is highlighted and displaying the submenu items.
PVX Precision Visual Thickness Gauge 6.3 Material Calibration In order for the PVX to make accurate measurements, it must be set to the correct sound velocity of the material being measured. Different types of materials have different inherent sound velocities. For example, the velocity of sound through steel is about 0.233 inches per microsecond, versus that of aluminum, which is about 0.248 inches per microsecond.
Dakota Ultrasonics 6) Repeat steps 4 & 5 until the velocity number is correctly displayed. 7) Press the OK key to set the velocity and return to the menu screen, or ESC to cancel entering the velocity. 8) Finally, press the MEAS key to return to the measurement screen and begin taking readings.
PVX Precision Visual Thickness Gauge One Point Calibration Note: Be sure that a probe zero has been done prior to performing this calibration procedure if a contact transducer in pulse-echo mode is being used. 1) Physically measure a location on the sample to be measured using a set of calipers or a digital micrometer.
Dakota Ultrasonics 4) Press the ENTER key to display the Digits Edit Box. 5) Press the UP and DOWN arrow keys to scroll the highlighted value. 6) Press the LEFT and RIGHT arrow keys to scroll the digit locations. 7) Repeat steps 5 & 6 until the known thickness value is correctly displayed. 8) Press the OK key to calculate the velocity and return to the menu screen, or ESC to cancel entering the velocity. 9) Finally, press the MEAS key to return to the measurement screen and begin taking readings.
PVX Precision Visual Thickness Gauge Note: If the user opted to do a setup from scratch for interface-echo (I-E) mode, a two point calibration must be performed to set the probe zero. 1) Using a set of calipers, physically measure two known thickness locations on the sample of material. Note: The two locations should represent the desired thickness range being measured. If the range is from .050” - .
Dakota Ultrasonics 9) Apply a drop of couplant on the transducer and place the transducer in steady contact with the sample or actual test material on the thinnest, or second known thickness location. Be sure that the reading is stable and the repeatability indicator, located in the top left corner of the display, is fully lit and stable. 10) Use the UP and DOWN arrow keys to highlight the TWO POINT calibration submenu item. 11) Press the ENTER key to display the Digits Edit Box.
PVX Precision Visual Thickness Gauge Built in Material Selection 1) Press the MENU key once to activate the menu items tab. Press the MENU key multiple times to tab right, and the ESC key multiple times to tab left, until the CAL menu is highlighted and displaying the submenu items. 2) Use the UP and DOWN arrow keys to scroll through the sub menu items until MATERIAL is highlighted. 3) Press the ENTER key to display the list of Material Types.
CHAPTER SEVEN USING THE A-SCAN & B-SCAN DISPLAYS A key feature of the PVX is the waveform display. The waveform is a graphical representation of the sound reflections returning to the transducer. Consider standing at the base of a canyon and screaming “Hello There”. After a brief delay, you will here multiple echoes, “Hello There’s” repeated back to you. The waveform display shows the amplitude of the signal received on the vertical (Y) axis and time (shown in units of thickness) on the horizontal (X) axis.
PVX Precision Visual Thickness Gauge 1) Press the MENU key once to activate the menu items tab. Press the MENU key multiple times to tab right, and the ESC key multiple times to tab left, until the DISP menu is highlighted and displaying the submenu items. 2) Use the UP and DOWN arrow keys to scroll through the sub menu items until VIEW is highlighted. 3) Use the LEFT and RIGHT arrow keys to scroll the view options.
Dakota Ultrasonics 7.2 Display Views RF View RF The RF mode shows the waveform in a similar fashion to an oscilloscope. It shows both the positive and the negative peaks. The peak (either positive or negative) selected for measurement is shown in upper portion of the display. This is the preferred mode for thin precision measuring modes, using delay line and pencil style transducers. It’s important to note that a measurement must fall inside the displays viewable range in order to see the waveform.
PVX Precision Visual Thickness Gauge C) Thickness Reading – Digital readout of thickness (inches or millimeters). D) Detect Indicator – The broken vertical line displays the zero crossing (flank) detection point on the waveform where the measurement has been obtained. Notice that the digital thickness readout is the same as the location of the detect indicator according to the measurements labels F, also in the diagram.
Dakota Ultrasonics Rectified View Rectified The rectified A-Scan mode shows half of the waveform. Either the positive or negative peaks are displayed, depending on the polarity selected. This is the preferred display view for flaw detection applications. It’s important to note that a measurement must fall inside the viewable display range in order to see the waveform. However, even if the waveform is outside of the viewable area, a measurement can be taken and viewed on the digital readout.
PVX Precision Visual Thickness Gauge E) Echo Signal – Graphical full waveform representation of the return echo displayed as an amplitude (vertical or “Y” axis) plotted against time (horizontal or “X” axis), this time is then converted to a physical measurement. F) Measurement Labels – The measurement labels are calculated and displayed according to where the left side of the display has been set (Delay), and the overall viewable area (Width) of the display.
Dakota Ultrasonics screen from right to left. Also notice at location J, the contour thickness changes of the bottom surface of the material. It’s important to note that the measurement range on the display be set wide enough, so that the maximum thickness of the material can be viewed on the display. Using the diagram above, if the material thickness was actually 1.75”, the underside of the material would not be viewable according to the current range at 0.00” – 1.00”.
PVX Precision Visual Thickness Gauge for instance, and passes over a flaw in the process, the scan bar will quickly deflect and alarm the user to go back and search for the defect. J) Contour (blind surface) – A view of the B-Scan displaying the blind side surface contour of the material. DIGITS VIEW DIGITS The Digits view is a basic digital thickness gauge look and feel. The larger digits make it much easier for the operator to monitor the thickness readings.
Dakota Ultrasonics display up into 5 segments, or quadrants. The measurement labels correspond to the measurement at each hash mark. G) Scan Bar – The scan bar corresponds directly with thickness represented by the horizontal labels on the on the display. As you can see from the diagram above, the filled horizontal bar is displayed at .500”. This display can be very useful when scanning materials in either B-Scan or Digits display views.
PVX Precision Visual Thickness Gauge 1) Press the MEAS key once to activate measure menu items. Press the MEAS key multiple times to move right and the ESC key multiple times to move left, until the WIDTH cell is highlighted. 2) Press the UP, DOWN, LEFT, and RIGHT arrow keys to scroll the highlighted value. 3) Alternatively , press the ENTER key to display the Digits Edit Box. 4) Press the UP and DOWN arrow keys to scroll the highlighted value.
Dakota Ultrasonics Adjusting the Width using the Tabbed Menus 1) Press the MENU key once to activate the menu items tab. Press the MENU key multiple times to tab right, and the ESC key multiple times to tab left, until the DISP menu is highlighted and displaying the submenu items. 2) Use the UP and DOWN arrow keys to scroll through the sub menu items until WIDTH is highlighted. 3) Press the LEFT and RIGHT arrow keys to scroll the value. When the correct width is being displayed, proceed to step 8.
PVX Precision Visual Thickness Gauge 9) Finally, press the MEAS key to return to the measurement screen and begin taking readings. Starting delay The starting DELAY, or starting depth, is the value displayed on the bottom lower left side of the display in both RF and RECT (Rectified) views. The DELAY will also be represented in both the BSCAN and DIGITS (Scan Bar) views, as the starting thickness depth. The starting depth is the minimum thickness value that can be viewed on the display.
Dakota Ultrasonics 4) Press the UP and DOWN arrow keys to scroll the highlighted value. 5) Press the LEFT and RIGHT arrow keys to scroll the digit locations. 6) Repeat steps 4 & 5 until the DELAY value is correctly displayed. 7) Press the OK key to return to the measurement screen, or ESC to cancel entering the DELAY. The user can also access and adjust the delay from the tabbed menus. However, this method is a more tedious process than making the adjustments using the Hot Menus.
PVX Precision Visual Thickness Gauge 4) Alternatively , press the ENTER key to display the Digits Edit Box. 5) Press the UP and DOWN arrow keys to scroll the highlighted value. 6) Press the LEFT and RIGHT arrow keys to scroll the digit locations. 7) Repeat steps 5 & 6 until the Delay number is correctly displayed. 8) Press the OK key to set the Delay and return to the menu screen, or ESC to cancel entering the Delay.
Dakota Ultrasonics 1) Press the MEAS key once to activate measure menu items. Press the MEAS key multiple times to move right, and the ESC key multiple times to move left until the GAIN cell is highlighted. 2) Press the UP, DOWN, LEFT, and RIGHT arrow keys to scroll the highlighted value. 3) Alternatively, press the ENTER key to display the Digits Edit Box. 4) Press the UP and DOWN arrow keys to scroll the highlighted value. 5) Press the LEFT and RIGHT arrow keys to scroll the digit locations.
PVX Precision Visual Thickness Gauge 1) Press the MENU key once to activate the menu items tab. Press the MENU key multiple times to tab right, and the ESC key multiple times to tab left, until the TUNE menu is highlighted and displaying the submenu items. 2) Use the UP and DOWN arrow keys to scroll through the sub menu items until GAIN is highlighted. 3) Press the LEFT and RIGHT arrow keys to scroll the value. When the correct Gain is being displayed, proceed to step 8 .
Dakota Ultrasonics 7.5 Threshold The Threshold is the level (sensitivity) of the signal amplitude required to trigger the thickness reading. This level can be used in conjunction with the gain. Example: suppose the user can visually see the waveform they need to detect on, but the PVX is not detecting because the Gain is too low, or the Threshold to high. The Threshold level can be decreased (lower sensitivity) in order to detect signals with lower amplitudes.
PVX Precision Visual Thickness Gauge Adjusting the Threshold using the Hot Menus 1) Press the MEAS key once to activate measure menu items. Press the MEAS key multiple times to move right and the ESC key multiple times to move left, until the THR (threshold) cell is highlighted. 2) Press the UP, DOWN, LEFT, and RIGHT arrow keys to scroll the highlighted value. 3) Alternatively, press the ENTER key to display the Digits Edit Box. 4) Press the UP and DOWN arrow keys to scroll the highlighted value.
Dakota Ultrasonics Adjusting the Threshold using the Tabbed Menus 1) Press the MENU key once to activate the menu items tab. Press the MENU key multiple times to tab right, and the ESC key multiple times to tab left, until the TUNE menu is highlighted and displaying the submenu items. 2) Use the UP and DOWN arrow keys to scroll through the sub menu items until THRESHOLD is highlighted. 3) Press the LEFT and RIGHT arrow keys to scroll the value.
PVX Precision Visual Thickness Gauge 7.6 Gates The PVX is equipped with two gates that can be adjusted by the user to measure a specific region or area on and between waveforms. In pulse - echo, only a single gate can be used. The single gate has a threshold and a start point. In echo – echo (interface-echo) mode, two gates are used. The same threshold level is associated with both gates.
Dakota Ultrasonics SURFACE NOISE PROBLEM NO GATE W/GATE The diagrams above illustrate a typical surface noise condition. Refer to the NO GATE diagram: (A) refers to the noise in front of the actual back wall signal (C). Notice that without a gate activated, the PVX is detecting on the noise (A) as shown at point (B). However, the true measurement should be taken at point (C).
PVX Precision Visual Thickness Gauge the noise (A) would have decreased below the threshold level, and the PVX would have also detected the true back wall (C). This example brings all the fine adjustments into consideration, and demonstrates the versatility of having fully functional scope rather than a basic digital thickness gauge. Adjusting Gate1 using the Hot Menus 1) Press the MEAS key once to activate measure menu items.
Dakota Ultrasonics The user can also access and adjust the gate from the tabbed menus. However, this method is more tedious than making the adjustments using the Hot Menus. The procedure using the tabbed menus is outlined below: Adjusting Gate1 using the Tabbed menus 1) Press the MENU key once to activate the menu items tab. Press the MENU key multiple times to tab right and the ESC key multiple times to tab left until the GATE menu is highlighted and displaying the submenu items.
PVX Precision Visual Thickness Gauge 9) Finally, press the MEAS key to return to the measurement screen and begin taking readings. Gate 2 The GATE 2 HOLDOFF is only used in the echo -echo (interface-echo) mode. Note: The PVX must be in E-E (echo-echo) mode to be activated. GATE 2 is sometimes called a Hold-Off or Delay. The function of the GATE HOLDOFF is to prevent the second gate from triggering on noise associated with ring down of the first echo.
Dakota Ultrasonics 2) Press the UP, DOWN, LEFT, and RIGHT arrow keys to scroll the highlighted value. 3) Alternatively, press the ENTER key to display the Digits Edit Box. 4) Press the UP and DOWN arrow keys to scroll the highlighted value. 5) Press the LEFT and RIGHT arrow keys to scroll the digit locations. 6) Repeat steps 4 & 5 until the GATE2 value is correctly displayed. 7) Press the OK key to return to the measurement screen, or ESC to cancel entering the GATE 2 value.
PVX Precision Visual Thickness Gauge 3) Press the LEFT and RIGHT arrow keys to scroll the value. When the correct gate value is being displayed, proceed to step 8 . 4) Alternatively, press the ENTER key to display the Digits Edit Box. 5) Press the UP and DOWN arrow keys to scroll the highlighted value. 6) Press the LEFT and RIGHT arrow keys to scroll the digit locations. 7) Repeat steps 5 & 6 until the GATE 2 value is correctly displayed.
CHAPTER EIGHT THRU PAINT MEASUREMENT TECHNIQUE 8.1 Introduction to Thru Paint Measurement The principle behind thru paint measurement is by measuring the time between two backwall echoes returning from the test material. Since both of these backwall echoes travel the same path through the paint or coating, the thickness of the coating is subtracted out of the measurement so that only the actual material thickness can be measured.
PVX Precision Visual Thickness Gauge The most straight forward way of setting up the PVX for thru paint measurements is to select a factory setup with a corresponding transducer type from the list of setups included with the PVX. These setups will serve as a good starting point for setting customized applications. However, fine adjustments may be necessary in order to be suitable for your specific applications.
Dakota Ultrasonics Notice that the amplitude of the cycle just to the left of (C). The amplitude of the cycle, a t (C), is less than the amplitude of the cycle at (B), in terms of overall height. If we decreased our gain, we would lose the first cycle (C) long before losing the second cycle (B). Therefore, adjusting the gain or threshold levels will not help us in this example. Our final option is adjusting the GATE2 hold-off, shown at point (C) in the incorrect diagram, to point (B) in the correct diagram.
CHAPTER NINE ADDITIONAL FEATURES OF THE PVX 9.1 Pulse Width The PVX has an adjustable pulse width option, located as a submenu item in the PROBE tab group. Pulse width, refers to the duration of time the pulser is left on. This time results in increased energy sent into the test material. There are three width options (SPIKE, THIN, and WIDE). The SPIKE setting may be desirable for high resolution and general applications to decrease the overall noise. This can be considered the normal or standard setting.
Dakota Ultrasonics 9.2 Auto Find The PVX is equipped with a very handy feature for locating the detection point of a back wall echo that is not currently in the viewable region of the display. Suppose the PVX is currently setup with a delay of 0.0” and a width of 0.500”, and the user is measuring material thickness of .625”. The PVX will make the correct measurement and display it digitally.
PVX Precision Visual Thickness Gauge 9.3 High Speed Scan The High Speed Scan feature of the PVX increases the overall sample rate from the standard 4 measurements a second to 32 measurements a second. This feature enables a user to make scanned passes over an arbitrary length of the test material, while still maintaining a reasonable representation of thickness over the scanned area or region.
Dakota Ultrasonics UTIL MENU – ALARM MODE Toggle Alarm Status (on/off) 1) Press the MENU key once to activate the menu items tab. Press the MENU key multiple times to tab right, and the ESC key multiple times to tab left, until the UTIL menu is highlighted and displaying the submenu items. 2) Use the UP and DOWN arrow keys to scroll through the sub menu items until ALARM STATUS is highlighted. 3) Use the LEFT and RIGHT arrow keys to toggle the ALARM STATUS on/off/audible.
PVX Precision Visual Thickness Gauge 4) Continue on to the next section “Setting the Alarm Lo Limit”. Setting the Alarm LO Limit 1) Assuming the ALARM STATUS is ON, use the UP and DOWN arrow keys to scroll through the sub menu items until ALARM LO LIMIT is highlighted. 2) Press the LEFT and RIGHT arrow keys to scroll the value. When the correct alarm value is being displayed, proceed to step 7 . 3) Alternatively , press the ENTER key to display the Digits Edit Box.
Dakota Ultrasonics Setting the Alarm HI Limit 1) Assuming the ALARM STATUS is ON,use the UP and DOWN arrow keys to scroll through the sub menu items until ALARM HI LIMIT is highlighted. 2) Press the LEFT and RIGHT arrow keys to scroll the value. When the correct alarm value is being displayed, proceed to step 8 . 3) Alternatively, press the ENTER key to display the Digits Edit Box. 4) Press the UP and DOWN arrow keys to scroll the highlighted value.
PVX Precision Visual Thickness Gauge Notice the +/- positions in the diagram. The positive phase is everything above the horizontal center line, and the negative everything below the center line. The PVX uses a zero crossing (flank) method for detection. Therefore, the detect line (A) is represented by the broken vertical dotted line, and is currently detecting on the negative portion of the waveform (B) at the zero crossing (C).
Dakota Ultrasonics view the positive and negative cycles of the waveform. Please refer to page 43 for information o n selecting the Display Views. 1) Press the MENU key once to activate the menu items tab. Press the MENU key multiple times to tab right, and the ESC key multiple times to tab left, until the TUNE menu is highlighted and displaying the submenu items. 2) Use the UP and DOWN arrow keys to scroll through the sub menu items until POLARITY is highlighted.
PVX Precision Visual Thickness Gauge Note: Before toggling the Rect Wave, the PVX should be set to the RECT display view option. Please refer to page 43 for information on selecting the Display Views. 1) Press the MENU key once to activate the menu items tab. Press the MENU key multiple times to tab right, and the ESC key multiple times to tab left, until the TUNE menu is highlighted and displaying the submenu items.
Dakota Ultrasonics 9.7 Language Selection The PVX is equipped with a multi language selection feature. This is an added feature for to accommodate everyone. The procedures are outlined below: Selecting the Language using the Tabbed Menus 1) Press the MENU key once to activate the menu items tab. Press the MENU key multiple times to tab right, and the ESC key multiple times to tab left, until the SETUP menu is highlighted and displaying the submenu items.
CHAPTER TEN DATA STORAGE – SETUP, EDIT, & VIEW GRIDS 10.1 Introduction to Grid (spreadsheet) format Data is stored in the PVX in a spreadsheet like format called a GRID. A GRID is simply a table of readings. The location in a grid is specified by giving a row and column coordinate. The rows are numbered from 1 to 99 and the columns are labeled from A to Z, then AA to ZZ giving a maximum of 52 possible columns. The largest grid that can be held in the PVX is limited by the total memory of the PVX.
Dakota Ultrasonics 1) Press the MENU key once to activate the menu items tab. Press the MENU key multiple times to tab right, and the ESC key multiple times to tab left, until the DATA menu is highlighted and displaying the submenu items. 2) Use the UP and DOWN arrow keys to scroll through the sub menu items until NEW is highlighted. 3) Press the ENTER key to display the new Grid Edit Box. 4) Use the UP and DOWN arrow keys to scroll through the new Grid List Items until NAME is highlighted.
PVX Precision Visual Thickness Gauge 10) Press the OK key to save the Grid Name and return to the Grid List Items menu, or ESC to cancel entering the Grid Name. Creating a Grid Note 1) Use the UP and DOWN arrow keys to scroll through the new Grid List Items until NOTE is highlighted. 2) Press the ENTER key to activate the Alpha Edit Box.
Dakota Ultrasonics 3) Use the UP, DOWN, LEFT, & RIGHT arrow keys to highlight the appropriate alpha characters. 4) Press the ENTER key to select a character and advance to the next field of the Grid Note. 5) Use the CLR key to backspace if necessary. 6) Repeat steps 3 through 5 until the Grid Note is completed. 7) Press the OK key to save the Grid Note and return to the Grid List Items menu, or ESC to cancel entering the Grid Note.
PVX Precision Visual Thickness Gauge 1) Use the UP and DOWN arrow keys to scroll through the new Grid List Items until TOP LEFT is highlighted. 2) Press the ENTER key to activate the Coordinate Edit Box. 3) Use the LEFT, & RIGHT arrow keys to scroll the Columns, and the UP, DOWN arrow keys to scroll the Rows. 4) Press the OK key to select the coordinate and return to the Grid List Items screen, or ESC to cancel the selection and return to the Grid List Items menu.
Dakota Ultrasonics 1) Use the UP and DOWN arrow keys to scroll through the new Grid List Items until LOWER RIGHT is highlighted. 2) Press the ENTER key to activate the Coordinate Edit Box. 3) Use the LEFT, & RIGHT arrow keys to scroll the Columns, and the UP, & DOWN arrow keys to scroll the Rows. 4) Press the OK key to select the coordinate and return to the Grid List Items screen, or ESC to cancel the selection and return to the Grid List Items menu.
PVX Precision Visual Thickness Gauge Note: If there is not enough memory available to create the grid, an error message box “NOT ENOUGH MEMORY“ will be displayed. Press the OK or ESC key to return to the Grid List Items menu. It may be necessary to free some memory in the PVX at this time. Refer to page 92 for more information on Deleting a Grid.
Dakota Ultrasonics Selecting the Auto Increment Direction The Auto Increment feature gives the user the ability to specify which direction to advance the cursor after storing a reading. 5) Use the UP and DOWN arrow keys to scroll through the new Grid List Items until INCR. DIR is highlighted. 6) Use the LEFT & RIGHT arrow keys to toggle the Increment direction NONE, NORTH, EAST, SOUTH, or WEST. 7) When the correct Increment direction is displayed, continue on to the next section “Saving the Grid”.
PVX Precision Visual Thickness Gauge Saving the Grid Once all the parameters are set, the user has the option of saving or canceling the new grid. 1) Use the UP and DOWN arrow keys to scroll through the new Grid List Items until CREATE NEW GRID? is highlighted. 2) Press the ENTER key to accept the grid parameters, and activate the confirmation screen. 3) Press the OK key to save the New Grid, or the ESC key to cancel the New Grid setup and return to the DATA menu.
Dakota Ultrasonics 4) Press the MEAS key to return to the measurement screen and begin storing readings. 10.3 Storing a reading Now that a grid has been created, it’s time to make some measurements and store the readings. The following procedures outline this process: Storing a Reading 1) Press the MEAS key once to activate measure menu items. Press the MEAS key multiple times to move right and the ESC key multiple times to move left until the LOC cell is highlighted.
PVX Precision Visual Thickness Gauge 5) Press the ENTER key to save the current reading in the highlighted cell location. 6) Abort the Grid View Box by pressing the MEAS key at any time. Note: Every time a reading is saved to memory, a picture of the display is automatically saved with the reading. 10.4 Viewing stored readings and waveforms It is sometimes necessary to go back and view the stored readings and waveforms using the PVX without a PC.
Dakota Ultrasonics a different cell, the display will be updated with the display view saved with the reading. Note: The user can also toggle the display view between RF, RECT, DIGiTS if previously saved in one of the listed modes, or B-SCAN and DIGITS if saved in B-Scan Mode, by pressing the ESC and OK keys while a location is highlighted. 4) The user may opt to clear a specific reading and save a new one at any time.
PVX Precision Visual Thickness Gauge 3) Press the ENTER key to display the Grid List Box. 4) Use the UP and DOWN arrow keys to scroll through the stored Grids until the target Grid to delete is highlighted. 5) Press the OK key to delete the Grid. 6) Press the MEAS key to return to the measurement screen. Deleting All Grids 1) Press the MENU key once to activate the menu items tab.
Dakota Ultrasonics 3) Press the ENTER key to activate the confirmation screen. 4) Press the OK key to delete All Grids from memory, or the ESC key to abort. 5) Press the MEAS key to return to the measurement screen. 10.6 Editing a grid Once a grid has been created and saved to memory, the user can edit the Comments or Increment Direction at a later time.
PVX Precision Visual Thickness Gauge 1) Press the MENU key once to activate the menu items tab. Press the MENU key multiple times to tab right and the ESC key multiple times to tab left until the DATA menu is highlighted and displaying the submenu items. 2) Use the UP and DOWN arrow keys to scroll through the sub menu items until EDIT is highlighted. 3) Press the ENTER key to display the Edit List Box. 4) Use the UP and DOWN arrow keys to scroll through the Edit options until NOTE or INCR.
Dakota Ultrasonics 9) Repeat steps 6 - 8 until the Comments are completed. 10) Press the UP or DOWN arrow key to highlight SAVE CHANGES, and the OK key to activate the confirmation screen. 11) Press the OK to save the changes or the ESC key to cancel editing the grid parameters. 12) Press the MEAS key to return to the measurement screen. 10.
PVX Precision Visual Thickness Gauge The user may have transferred grid templates from a PC to the PVX, or setup grids using the PVX at an earlier time. The name of the currently active grid is always displayed at the bottom of the Hot Menu Items in measurement mode. It’s not only important to recognize what grid is currently active, but also be able to change the active grid at any time.
Dakota Ultrasonics 5) Press the ENTER key to activate the confirmation screen. 6) Press the OK key to load the grid from memory. 7) Press the MEAS key to return to the measure screen.
CHAPTER ELEVEN SETUPS – CREATE, STORE, EDIT, & RECALL 11.1 Introduction to Setups Often times, users are faced with a variety of tasks and applications that are sometimes similar, but often times very different. With a standard thickness gauge, the user would have to recalibrate for each individual application respectively. With all the features of the PVX, the number of potential applications also increases based on ability alone.
Dakota Ultrasonics Opening a Setup Note: The setups can be loaded at any time by simply pressing the MULTI MODE key. 1) Press the MENU key once to activate the menu items tab. Press the MENU key multiple times to tab right and the ESC key multiple times to tab left until the SETUP menu is highlighted and displaying the submenu items. 2) Use the UP and DOWN arrow keys to scroll through the sub menu items until OPEN is highlighted. 3) Press the ENTER key to display the Setup List Box.
PVX Precision Visual Thickness Gauge 5) Press the ENTER key to activate the confirmation screen. 6) Press the OK key to load the setup from memory. 7) Press the MEAS key to return to the measure screen. 11.3 Saving a Setup Once the PVX parameters and features have be adjusted for an application, the user may elect to save these setting to a specific setup location for future use. This can potentially save time and reduce error between users.
Dakota Ultrasonics Saving the Setup 1) Press the MENU key once to activate the menu items tab. Press the MENU key multiple times to tab right and the ESC key multiple times to tab left until the SETUP menu is highlighted and displaying the submenu items. 2) Use the UP and DOWN arrow keys to scroll through the sub menu items until SAVE is highlighted. 3) Press the ENTER key to display the Save Setup Parameters List Box. 4) Press the UP and DOWN arrow keys to scroll the Name and Note parameters.
PVX Precision Visual Thickness Gauge 5) When the parameter to edit is highlighted, press the ENTER key to activate the Alpha Edit Box. 6) Use the UP, DOWN, LEFT, and RIGHT arrow keys to scroll through the characters, the ENTER key to select characters, and the CLR key to backspace through the characters, until the Name or Note fields have been edited. 7) Press the OK key to return to the Save Setup Parameters List Box. 8) If both parameters will be edited, repeat steps 4 – 7.
Dakota Ultrasonics Note: The Name and Comments of the Setup can be edited at any time by simply repeating the Save Setup routine described above. Therefore, the Save Setup function can also be considered an Edit Function. 11.4 Using the Default Setup The default setup feature was added to the PVX to use, as a last resort, if there are no setups stored in the gauge –factory or otherwise.
PVX Precision Visual Thickness Gauge Important Note: Remember to perform a probe zero function prior to measuring. The default setup clears the probe zero value. Important Note: If interface-echo or echo-echo modes are being used, be sure to do a two -point calibration, which also sets the probe zero before measuring. 4) Press the OK key to return to the measurement screen.
Dakota Ultrasonics CHAPTER TWELVE USING THE UTILITY SOFTWARE 12.1 Computer System Requirements DakView 3 or PVXview will run on many different operating systems: Windows 95, Windows 98 (1st or 2nd edition), Windows NT 4.0 with Service Pack 5, Windows ME, Windows XP, Windows 2000 Professional, Windows 2000 Server, or Windows 2000 Advanced Server operating systems running on Intel or AMD hardware. A Pentium 166MHz or faster processor with at least 32 megabytes of p hysical RAM is required.
APPENDIX A VELOCITY TABLE Material sound velocity in/us sound velocity m/s Aluminum Beryllium Brass Bronze Cadmium Columbium Copper Glass (plate) Glycerine Gold Inconel Iron Cast Iron Lead Magnesium Mercury Molybdenum Monel Nickel Nylon Platinum Plexiglas Polystyrene PVC Quartz glass Rubber vulcanized Silver Steel (1020) Steel (4340) Steel Stainless" Teflon 0.2510 0.5080 0.1730 0.1390 0.1090 0.1940 0.1830 0.2270 0.0760 0.1280 0.2290 0.2320 0.1800 0.0850 0.2300 0.0570 0.2460 0.2110 0.2220 0.1060 0.
Dakota Ultrasonics Tin Titanium Tungsten Uranium Water Zinc Zirconium 108 0.1310 0.2400 0.2040 0.1330 0.0580 0.1660 0.
APPENDIX B SETUP LIBRARY Num Name 1 2 Gn/AGC Velocity E-E DELAY LINE 3/8 3 0.2330 in/uSec I-E DELAY LINE 3/8 3 0.2330 in/uSec 3 4 E-E DELAY LINE 1/2 I-E DELAY LINE 1/2 3 3 0.2330 in/uSec 0.2510 in/uSec 5 E-E GRAPHITE STEEL 3 0.0940 in/uSec 6 I-E GRAPHITE STEEL 3 0.0940 in/uSec 7 8 I-E GRAPHITE PLASTIC E-E PENCIL PTR-100E 3 3 0.0920 in/uSec 0.2330 in/uSec 9 I-E PENCIL PTR-100E 3 0.2330 in/uSec 10 E-E PENCIL PTR-300E 6 0.
MATERIAL SAFETY DATA SHEET N/A = not applicable or not available (To comply with 29 CFR 1910.1200) Effective Date: 2/1/04 SECTION 1 – PRODUCT IDENTIFICATION NFPA Hazardous Materials Identification System (est) Health……………………0 Flammability…………….0 Reactivity………………..0 Product Name: SOUNDSAFE Generic Name: Ultrasonic Couplant Manufacturer: Sonotech, Inc. 774 Marine Dr.