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Page 64 of 65

10     Care and Maintenance

10. 

Care and Maintenance

10.1    Cleaning

Cleaning can be done with a cloth dampened with warm soapy water. Do not use scouring pads on the casing or display 
surfaces as this will scratch the device. Do not submerge or pour water over the receiver or transmitter.

Always dry the equipment before storing it.

10.2    Checking Functionality

The vLoc3-DM system can be checked using a simple test procedure. It requires an area clear of pipes and cables and free 
from metallic structures such as metal tanks, metal railings, and reinforced concrete.

A 40m square loop of wire needs to be set out on the ground with a non-metallic structure placed at 1m above the cable and at 
the midpoint of one of the straight sections. See the diagram below.

40m

Insulated Cable

1m

Black (green)

Cable

Red (white)

Cable

Method:

•  Set the transmitter to 128Hz (98Hz if in a 60Hz environment)/3Hz/6Hz, set the current to 100mA.
•  Set the locator to receive 128Hz (or 98Hz). Position the locator on the non-metallic structure and carefully align it above and 

in line with the cable. Set the gain of the locator to read approximately 50%. Check that the line indicator is pointing North/
South. If it is not, there could be an interfering signal, or you may be too near to a bend of the loop.

•  Hold the locator very still and press the “i” pushbutton. After a few seconds a result will be displayed on the instrument.
•  Check that the arrow is pointing back towards the white (or red) connection lead.
•  Check the vLoc3-DM current reading is 100mA +/-10mA (10%).
•  Check the depth is 1m +/-7cm.
•  Repeat for each of the current settings of the transmitter.
•  Successful completion of these tests confirms that both the receiver and transmitter are functional.

Содержание vLoc3-DM

Страница 1: ...vLoc3 DM Defect Mapper User Handbook English Edition Version 1 1 P N 4 04 000171 ...

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Страница 3: ...puters Generally they have a life of three to five years Under no circumstances should any attempt be made to charge these batteries Dispose of according to your company s work practice environmental standards the prevailing laws or recognized best practice Always dispose of batteries responsibly 5 General Rules regarding Disposal of Batteries Never disassemble a battery or battery pack Never disp...

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Страница 5: ... 14 3 8 vLoc3 Series Locate Modes and Screens 16 3 8 1 The Classic Screen Status Bar 16 3 8 2 vLoc3 DM Receiver Classic Screen 16 3 9 Classic Locating Modes Response 17 3 10 Alternative Locate Screens 19 3 10 1 The Vector Screen 19 3 10 2 The Transverse Plot Screen 20 3 10 3 The Plan View Screen 21 4 Using the vLoc3 DM Receiver 23 4 1 Passive Locating 23 4 1 1 Detecting Power Signals 23 4 1 2 Dete...

Страница 6: ...onnections 47 6 4 Connecting to a Pipeline 47 6 4 1 Connecting at a CP Cathodic Protection Station 47 6 4 2 Connecting to the Pipe when there is No Access to a CP Station 49 6 5 Selecting the Correct Frequency 49 6 6 Output Current Select 50 6 7 Alarms 50 6 7 1 Over Voltage 50 6 7 2 Over Temperature 50 6 7 3 Overpower 50 7 Using External GPS 51 7 1 Compatible GPS and GPS Data Loggers 51 7 2 Blueto...

Страница 7: ... Fields 59 9 2 2 2 Checking for Distorted Fields 60 9 3 Viewing Data 61 9 3 1 Viewing xls Files 61 9 3 2 Viewing kml Files 62 9 4 Interpreting Graphs 63 10 Care and Maintenance 64 10 1 Cleaning 64 10 2 Checking Functionality 64 11 Glossary 65 ...

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Страница 9: ...r On both receiver and transmitter the software revision number is displayed on the LCD during the startup sequence if the default start screen is used It can also be found in the About section of the user menu Receivers with the Tx Link option installed will show this icon label on the blade where it meets the yellow upper housing Transmitters with the Tx Link option installed will show this icon...

Страница 10: ...7 Website www vivax metrotech com Email LatinSales vxmt com Central South America and the Caribbean Vivax Metrotech AUS Unit 1 176 South Creek Road Cromer NSW 2099 Australia Tel 61 2 9972 9244 Fax 61 2 9972 9433 Website www vivax metrotechaus com Email sales vxmtaus com service vxmtaus com Shanghai Vimap Technology Co Ltd 9 F Building 89 Xinhuiyuan No 1122 Qinzhou North Road Shanghai China 200233 ...

Страница 11: ... These measurement results are displayed on the screen of the receiver The measurements and data are logged into the receiver for downloading to spreadsheets or dedicated analysis programs There is no need to carry extra logging and display devices An internal 3m accuracy GPS antenna is included with the system Alternatively a Bluetooth enabled GPS device can be linked to the vLoc3 DM receiver via...

Страница 12: ...he previous and after CP stations disconnected from the pipeline s stretch to be surveyed Remember that the pipeline is not protected while the survey is being undertaken so CP stations unnecessary downtime should be avoided Choose the survey interval to match the condition of the pipeline In areas where the coating is inferior a survey interval of as little as 10m may be desirable However if the ...

Страница 13: ...e for charger 8 vLoc3 DM Low Frequency Sensor 9 Sensor Blanking Plate 10 User manual 11 Soft carry bag 1 2 3 4 5 6 7 8 9 10 11 1 Pushbutton keypad and display 7 Accessory socket and charging point 2 Model number serial number 8 Expansion sockets for additional features such as the Bluetooth module 3 Battery retaining cover 4 AA Alkaline battery pack rechargeable battery pack 9 Receiver stem 5 Mini...

Страница 14: ...bottom of the receiver stem counter clockwise for turn Grasp the low frequency sensor and rotate it counterclockwise until it releases Now fit the blanking plate supplied by following the above instructions in reverse order IMPORTANT Always install the blanking plate when the low frequency sensor foot is not attached There are critical contacts within the antenna tube that require protection Failu...

Страница 15: ...ing the unit in extreme temperature conditions i e below 0ºC and above 45ºC Although Vivax Metrotech batteries include all the required safety related features immediately discontinue the charger and battery pack s use if the battery pack becomes excessively warm Return both to where they were purchased for investigation Always ensure batteries have at least a partial charge if storing for long pe...

Страница 16: ...back to Locate Screen Increase scaling Decrease gain Reject and Jump back to the Locate Screen Press to delete a log in memory Reduce scaling Change antenna mode Go to Graph Screen Change scaling aspect see next chart When in the graphing Mode Screen the soft key operated by the key has the following functions as indicated by the changing icon Softkey icons in the Graph mode Function and Scale the...

Страница 17: ...ated with this button To exit the menu or sub menu press the i button Where the icon is not shown the enter button is used to scroll through the options of that feature Use the and buttons to scroll up and down through the menu Menu DFT New Survey Regulatory Labels Internal Menu Continuous Information Auto Power Off Warnings GPS Source Bluetooth Pairing Bluetooth Auto Connect Self Test Depth curre...

Страница 18: ...nu Scroll up and down the table of available frequencies using the and keys Simplify the operation of the receiver by selecting only the frequencies applicable to your applications To do this use the enter key to check the boxes on the right Frequencies not checked will not appear on the locate screen Frequency 1 45kHz 2 0kHz 8 01kHz 8 19kHz 8KFF 8 44kHz 9 5kHz 9 8kHz Note also that specific frequ...

Страница 19: ... to the top of the pipe i e the cover depth To enter a pipe diameter enter the user menu by using a long press of the info key When in the User Menu and scroll to DM Pipe Diameter Menu Blacklight Frequency DM Frequency DM Current DM Simultaneous Info DM Current Warning Pipe Diameter Medium 3Hz 6Hz Live Disabled Disabled Use the Enter key to enable the diameter of the pipe to be entered 0 10cm 30cm...

Страница 20: ...er in the manual The options are Locate Perspective Classic Locate Vector Locate Transverse Graph Plan View Sonde 3 5 3 Setup Features Warnings Warnings relating to Shallow cable Overload Overhead cable and Signal Overload Scroll down to the relevant warning and use the return button to select or de select GPS Source Use the Enter key to select the source of Internal or Bluetooth Internal The vLoc...

Страница 21: ...ous log record Electric Gas etc Communications Potable Water Reclaimed Water Sewer Temporary Survey Proposed Excavation Oil 3 5 4 Setup Informational About This section holds the data about the locator such as software revision calibration data etc Regulatory Labels This section shows the required FCC ID and IC information Self Test The vLoc3 series receivers have a self test feature that confirms...

Страница 22: ...ely resulting in misleading information When sweeping the locator across the direction of the line try to keep it vertical as this will improve its accuracy Overhead Cable alerts indicate that the source of the signal is mainly radiating from above This alert is usually caused by the signal traveling along overhead cables 3 7 2 DFT Discrete Fourier Transform DFT is a tool to assist in choosing a f...

Страница 23: ...ng from 0dB to 140dB will be presented next to the frequency list with 140dB being the least possible interference detected and 0db with the largest amount of possible interference 7 The results are ranked from the least interference possible at the top to the largest amount of most possible interference at the bottom 8 In this case 491Hz with 80dB is the frequency with the least interference dete...

Страница 24: ...ed Black indicates installed but not active Blue indicates active and paired 2 This icon is shown in this position when the low frequency sensor is fitted and active 5 GPS status Green indicates GPS signal lock 3 Continuous Signal Current and Depth of the target line can be set to show continuous signal current continuous depth or both 6 Speaker volume setting 7 Battery type and remaining charge 3...

Страница 25: ...ines because using a single antenna can boost the received signal The compass line direction indicator aligns itself parallel to the cable available in active modes Null Mode The vertical Null antennas receive a minimum or Null response over the buried line The null mode works well in uncongested areas but is more prone to inaccuracies due to the effects of field distortion This effect can be used...

Страница 26: ...ture is available in the Peak and Broad peak modes Information Pushbutton Depth Current Info screen shown with the low frequency sensor removed Log 0 0 78m 233mA 50 42 59 90570 N 3 26 35 54358 W 27 50m 0 SD 233mA A quick press of the i information pushbutton will display the depth and signal current information in a locate screen The top left of the display shows longitude latitude positional info...

Страница 27: ... 86m 0 2m 85 6mA 3 2 1 6 7 4 5 1462cm 8 1 Frequency selected 2 Signal current 3 Depth to the target line 4 Horizontal distance to the target 5 Scaling adjust with keys 6 Plan View of the target 7 Cross section view that shows vectors to target 8 Distance from last low frequency measurement Using the Vector screen 1 Apply the signal to the target line in the usual manner and select the Vector scree...

Страница 28: ...locator on one side of the target IMPORTANT When taking Low Frequency measurements ie 3 or 4Hz current measurements it is important to be directly over the line 3 10 2 The Transverse Plot Screen Using the Transverse Plot screen The Transverse Plot screen is used to analyze the field shape at a particular location enabling the user to better feel for the data s reliability Two plots are generated s...

Страница 29: ...ply the signal to the target line in the usual manner and select the Plan View screen by a long press on the return button until the desired screen appears 2 Position the locator within the approximate position of the target line Use the Plan View to help guide you toward the target line You can imagine that the plan view is giving you a view into the ground 3 Position yourself so that the target ...

Страница 30: ... e the locator does not need to be aligned with the target line in the forward back orientation It is recommended in this mode The current is always displayed as the signal may bleed off onto other services Regular checks on the signal current i e checking for large changes will ensure the correct line is detected 1 2m 4 5mA 6 A short press on the info button will display the information screen Mo...

Страница 31: ... When electrical power is distributed throughout the network some power finds its way back to the power station via the ground These stray currents can jump onto pipes and cables and also create power signals Note that there has to be an electrical current flowing to create a detectable signal For instance a live cable that is not in use may not radiate a detectable signal Also a well balanced cab...

Страница 32: ...22dB 0cm 4 5m 7 Rotate the vLoc3 receiver on its axis to obtain the maximum signal The vLoc3 receiver is now directly over the line and with the blade across the line If using the Omni Peak mode there will be no change so switch to Peak mode if the direction is required 8 The direction can also be found by rotating until the smallest signal is detected The blade is then in line with the cable pipe...

Страница 33: ...ower frequencies travel further with less bleed off onto nearby utilities than higher frequencies When using the signal clamp with the Loc3 25Tx 25 watt transmitter the clamp frequencies available are limited between 8kHz and 10kHz A transmitter is required to apply a locate signal Depending on the transmitter model the transmitters locate signal can be applied by direct connection or transmitter ...

Страница 34: ...the magnet A good example of this is to make a connection to a street lighting circuit Usually it is the practice to connect the sheath of a lighting cable to a street lamp s metallic inspection cover Making a connection to the inspection plate will energize the cable via the plate and sheath Usually there is no projection on which to clip so using the magnet on the plate provides a suitable clipp...

Страница 35: ...ose them WARNING Always follow the appropriate safety requirements mandated by safety legislation safety practice and your company s safety procedures when applying a clamp coupler to a cable BEWARE that when placing a clamp around cables carrying high current the clamp may vibrate jump or close violently due to induced current from the target cable High voltages can be induced back onto the clamp...

Страница 36: ...on of the pipe 4 4 Pinpointing Before measurements are taken it is necessary to pinpoint the pipeline precisely To do this use the following steps Rotate the locator so that the compass line direction indicator is pointing north south Move the locator in the direction indicated by the arrow Stop when the arrow changes to the opposite direction Adjust the gain by pressing the or pushbuttons so that...

Страница 37: ...ceiver very stationary and press the i pushbutton The display will show the following screen while the measurement is made 27 50m 1 05m 79 o 59 55 95961 N 179 o 59 55 95961 W Please hold still After approximately two seconds the rotating circle and progress bar will be replaced with a display similar to the below 27 50m 0 75m 79 o 59 55 95961 N 179 o 59 55 95961 W 0 00m 428 263mA 3 6Hz 1 2 3 4 5 6...

Страница 38: ...an onscreen graphing facility Access to this facility is through the info screen Press the enter key when in the Info screen 27 50m 0 75m 79 o 59 55 95961 N 179 o 59 55 95961 W 0 00m 428 263mA 3 6Hz Graphing icon The graphing screen is displayed below Log 7 1 09mA 0cm 345 05m 37 03m When in the graphing mode screen the soft key operated by the key has the following functions as indicated by the ch...

Страница 39: ...orizontal plains depending on the axis chosen When the Auto Scale icon is shown press the f key to auto scale Press the i button to return to the locate screen 4 9 The Walk back feature When in the graphing mode and receiving a valid GPS lock except the Review screen the graph will have a vertical line indicating the position of the locator along the pipeline While undertaking the survey the verti...

Страница 40: ...power system is 50Hz Locate the pipe The receiver may or may not be flashing the SD Forward Back arrows icon The arrows appear differently depending on what locate screen is used but follow the convention of green for forward and red for backward This section of the manual assumes a conventional screen is used but for reference the other screens show the arrow as below SD USA 1 41m 0 15m 0 0 8m 84...

Страница 41: ... red backward arrow illuminates at any time this indicates that the wrong line is being located 62 6 SD USA 25dB 80 8mA 0 27m 0 00m 62 6 SD USA 25dB 80 8mA 0 27m 0 00m At some point you may find that the SD arrow starts to flash The flashing SD arrow indicates that synchronization with the transmitter has deteriorated and a reset is required 62 6 SD USA 25dB 80 8mA 0 27m 0 00m Re trace your line b...

Страница 42: ...puncture the ground with the spikes Fully inserting them is only necessary where the ground conditions are particularly dry or high resistance The A frame should be plugged into the accessory port The receiver will automatically recognize the A frame and enter the fault find mode The display will be similar to the one below 96 dB 98Hz 3 6Hz 1 0 00m 1 2 3 4 5 6 7 8 9 10 11 12 13 14 1 Locate frequen...

Страница 43: ...ate section of the screen to position the A frame above the pipe The signal strength will be displayed and if the signal is strong enough an arrow will point forward Press the pushbutton to save the reading This will enter the result into the graph The scaling of the graph is automated and may change as points are added Only the last 20 records will be shown on the screen If you need to review oth...

Страница 44: ...ng the A frame where there are Many Defects Such as Porous Coating Poorly coated pipelines such as old bitumen coating may create a confusing result when multiple defects interfere with each other To overcome this it is sometimes beneficial to adopt a different approach This alternative approach involves using the A frame perpendicular and to one side of the pipeline See the diagram below Note the...

Страница 45: ...e available and both enable simultaneous ACVG and current gradient mapping To take a DM current reading when in the A Frame mode press the Info key If in simultaneous mode the following will be displayed 40 7m 1 18m 50 o 42 59 90570 N 3 o 26 35 54358 W 0 00m 146 584mA 3 6Hz 96 dB Pressing the Enter key will save both A frame and DM current readings If in standard mode the display below will be dis...

Страница 46: ...on lead Loc3 25Tx 6 Ground stake 7 Mini USB lead 5 2 Display 4Hz 98Hz 3 9 0 mA 1 2 4 5 6 7 8 3 1 High Voltage Warning 2 Active frequency 3 Mode indication icon 4 Units mA volts ohms 5 Speaker level 6 Output step bar graph 7 Battery level or DC Input icon 8 Digital readout mA volts ohms Output Protect Warning The transmitter checks the line when connected Output protected against accidental momenta...

Страница 47: ...enu Structure Volume Voltage Resistance LCD Contrast Receiver Link Disabled Frequency Menu About When the i information pushbutton is pressed the display will show the volume level Use the and pushbuttons to increase reduce or turn the speaker off off low medium high Keep pressing the i information pushbutton and the display can be toggled to show voltage resistance or other functions as shown in ...

Страница 48: ... Follow instructions detailed in the General Safety Care Information section of this document Dispose of batteries following your company s practice and environmental standards the prevailing laws or recognized best practice Always dispose of batteries responsibly The 25 watt transmitter ships with the Li ion battery tray An optional alkaline tray can be used with the 25 watt transmitter but the p...

Страница 49: ...s manual Only use the battery charger supplied as using an unapproved charger may damage the battery pack and may cause overheating 5 7 Removing and Installing the Battery Tray These procedures apply to both the Alkaline or Rechargeable battery tray Removing the 25 watt transmitter battery tray 1 Reach under the catch and pull to unlock 2 Lift up the catch and repeat for all four catches 3 Lift th...

Страница 50: ... beep rate from the speaker and the current reading on the display FUSE Wherever a direct connection can be safely made without the risk of injury damage to the customer s plant or the transmitter it is the best way of applying the transmitter s signal The positioning of the ground connection can also influence the degree of coupling experienced Ground connections generally should not be made to o...

Страница 51: ...f transmitting frequencies The factory will preset the most commonly used frequencies Additional frequencies are available to be selected in the frequencies list 5 8 4 Frequencies and Maximum Power Output Frequencies power outputs Loc3 25Tx Direct connection 25 watt 32Hz 9 82kHz Pushbutton Pushbutton 4Hz 128Hz 3Hz 128Hz 4Hz 8Hz 128Hz 4Hz 8Hz 512Hz 4Hz 8Hz 128Hz 8 19kHz 512Hz 128Hz As with most man...

Страница 52: ...the user can work with only their preferred frequencies rather than having a more extensive list of frequencies to scroll through Enter the Frequency Menu 1 Press the i pushbutton four to six times based on the mode that the transmitter is in until reaching the Frequency menu sub menu In Direct Connection mode Volume Voltage Resistance LCD Contrast Receiver Link Disabled Frequency Menu About In SD...

Страница 53: ...tup menu 1 Press the i pushbutton seven times to get to the Multi Frequency screen and press the f pushbutton to activate the multi frequency mode An x symbol will appear indicating that the multi frequency mode is activated Press the f pushbutton again to go to the Multi Frequency Setup screen to choose the frequencies Volume Voltage Resistance Multi Frequency LCD Contrast Receiver Link Disabled ...

Страница 54: ...4 Signal Output Cable 5 DC power cord 2 1 3 4 Ref Control Function 1 Power To power on off the unit 2 LCD Display View menu status and information from the transmitter 3 Output Current Active Standby Rotate rotary switch to select output current Press and hold to power on or standby 4 Frequency Status Rotate rotary switch to select a frequency Press momentarily to view status refer to status scree...

Страница 55: ... 100V it will display an overvoltage alarm 6 3 Power Supplies and Connections 1 2 3 4 5 1 Mains Input 2 Mains Input Fuse 5A 250V 3 12 60V DC Input 4 Output Fuse 10A 250V 5 Output Socket 6 4 Connecting to a Pipeline 6 4 1 Connecting at a CP Cathodic Protection Station WARNING Connecting to the CP station involves removing connections from the CP transformer rectifier and should only be performed by...

Страница 56: ...lead to the socket CP Station Ve Ve Mains Socket Mains Input Disconnect Leads from CP station To Anode Bed Red Black Making the connection at the CP Station using the Mains Socket to power up the transmitter 4 If there is no main socket it is possible to use the transformer rectifier s DC output See the diagram below CP Station Ve Ve Disconnect leads from CP station Red Black To Anode Bed Black Re...

Страница 57: ...ground will need to be generated by driving a ground stake into the ground a few meters perpendicular to the pipe The ground needs to be low impedance so the copper ground rod needs to be at least 0 5 meters long In some cases multiple stakes may be necessary A poor ground will result in the transmitter showing the overvoltage alarm even at low currents If this occurs add more ground rods connecte...

Страница 58: ... the output will not be stabilized To overcome this select a lower current setting Other causes of overvoltage alarms are 1 Pipeline in very good condition small high impedance faults will require higher voltages to achieve the requested current 2 Poor anode bed Poor anode beds will require a high voltage drop across them to create the requested current 3 Poor pipe connections 6 7 Alarms 6 7 1 Ove...

Страница 59: ...ted 6 If the Bluetooth icon is grey this means the GPS option is not fitted or incorrectly fitted 7 The Bluetooth can communicate with external devices that are also Bluetooth enabled Generally Bluetooth devices fall into two categories high or low power devices vLoc3 DM Bluetooth is compatible with low power devices 7 3 Pairing with external GPS Dataloggers To pair with an external device first e...

Страница 60: ...ired with an external device see the previous section on Bluetooth devices Once paired with an external device the vLoc3 DM will await valid GPS data from the external device The GPS icon will turn green when a valid GPS signal is detected The change can take from a few seconds to a few minutes depending on the device and whether it is doing a cold or hot start 50 42 59 90570 N 3 26 35 54358 W 27 ...

Страница 61: ...The locator s configurations and settings can be locked enabling equipment or safety officers to ensure that users cannot override features selected or removed by management requires optional lockout dongle The first part of this manual Basic Operation describes usage not requiring a USB security dongle The second part of this document Advanced Features describes usage requiring a security dongle ...

Страница 62: ...on number is checked against the latest version available on the Vivax Metrotech server The user is notified if an update is available as shown below This feature will only be available if the computer is online Clicking on the Update Now button will download the latest version from the Vivax Metrotech server which the user can install ...

Страница 63: ...cation s needs while keeping the user interface uncluttered The toolbar at the top of the screen enables the user to create configurations The application toolbar looks like this New vmcfg MyLocator3 Opens an existing configuration file vmcfg Reads the configuration from the connected locator Saves the configuration to a file Displays information about MyLocator3 Writes the configuration to the co...

Страница 64: ...d to fit the width of the screen If the scaled image height is less than the LCD height then the image is centered vertically and white bars are used as padding If the scaled image height is greater than the LCD height the image can be re positioned vertically by clicking and dragging the left mouse button anywhere on the image To insert your startup screen first click on the Open button Then brow...

Страница 65: ...sferring Data from the Locator 8 2 7 Frequencies Page The Frequencies page will allow the user to refine which frequency modes are available when the locator F key is pressed and which frequencies appear on the locator menu ...

Страница 66: ... two for Vivax Metrotech s distributors repair centers managers and level three for Vivax Metrotech use only 8 3 1 Supervisor Lockouts This feature is available to anyone with a dongle Contact Vivax Metrotech to purchase a dongle When a dongle is connected to your computer via a standard USB socket the icons for the Splash Screen page Frequencies page and the Menu Settings page will change color t...

Страница 67: ...rong earth s magnetic field to induce an interfering signal into the sensors resulting in errors The vLoc3 DM must be kept still while it is taking measurements 9 2 2 Interference Distorted Fields The vLoc3 DM evaluates the electromagnetic field signal radiating from a pipeline to determine the information required It assumed that the field is uniformly radiating from the pipe Unfortunately the fi...

Страница 68: ...leeving It is common practice to insert a pipe in a protective steel sleeve This may distort the signal and cause errors Take readings before and after the sleeve If they are the same the pipeline is well insulated through the sleeve Sleeves are very often used at road crossings 9 2 2 2 Checking for Distorted Fields Check to see if other radiated fields are distorting the signal Locate the pipe fi...

Страница 69: ...n is populated automatically as the GPS option was used when data were collected If GPS was not used the distance between measurements would have to be inserted manually It is now possible to generate a graph Graphs are most commonly done as vLoc3 DM current against distance Highlight the Accumulated Distance records and then press the Ctrl key while highlighting the vLoc3 DM Current column From t...

Страница 70: ...e If connected to the web and if the Google Earth application is installed on the host computer Google Earth will automatically launch and zoom to the site location Pins will indicate survey points Clicking on a point will show measurement details for that point note these details are continually under review and may change without notice The map is a typical representation but note that this feat...

Страница 71: ...e is a defect at this point However looking at points 1 to 20 shows that there is in fact a trend of signal loss at points 10 13 which is the more likely fault location 4 3 2 1 mA Distance Graph A 5 6 7 8 9 10 11 12 13 14 15 17 18 19 20 16 Also note the step response at points 1 to 2 This is typical of readings near the application point and may not represent a fault The step is often caused by th...

Страница 72: ...agram below 40m Insulated Cable 1m Black green Cable Red white Cable Method Set the transmitter to 128Hz 98Hz if in a 60Hz environment 3Hz 6Hz set the current to 100mA Set the locator to receive 128Hz or 98Hz Position the locator on the non metallic structure and carefully align it above and in line with the cable Set the gain of the locator to read approximately 50 Check that the line indicator i...

Страница 73: ...60Hz and LF VLF radio Passive signals A wide range of signals that radiate from buried pipes or cables These signals come from various sources in the environment and couple to the buried overhead lines Typical examples 50 60Hz and LF VLF radio Peak A maximum response to a buried line Pinpoint Using a receiver to identify the exact position of a buried line Response The indication that the receiver...

Страница 74: ... Notes Vivax Metrotech Corporation 3251 Olcott Street Santa Clara CA 95054 USA Toll Free 1 800 446 3392 Phone 1 408 734 1400 Website www vivax metrotech com ...

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