Digitrex 3-3000-00a-F manual Signal Interference, Electrical Interference/Background Noise Check

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DIGITAL CONTROL INCORPORATED

Signal Interference

Before drilling (preferably before bidding on a project) the interference potential at your site(s) should be evaluated. Interference can reduce the transmitter’s range or cause variable readings and possibly result in job slowdowns. Interference comes from two different types of sources: active and passive.

Active interference is also known as electrical interference or noise and can have varying effects upon the DigiTrak locating equipment. Most electrical devices emit signals. Because DCI receivers have two types of antennas in them (depth and roll/pitch), it is possible to have interference that affects one or both signals. Some examples of active interference are traffic signal loops, buried dog fences, cathodic pro- tection, radio communications, microwave towers, cable TV, fiber-trace lines, utility data transmissions, security systems, power lines, and phone lines.

Passive interference sources (listed below) can reduce the amount of signal received or reradiate the transmitter’s signal. This can cause erroneous depth readings or, in extreme cases, no signal, i.e., “1999” in the bottom window. In addition, the FNLP and RNLP (discussed in the Locating Section) may be affected. Some examples of passive interference are:

¾Metal (pipes, rebar, trench plate, chain-link fence, engine blocks, etc.) – Metal acts as an antenna and can therefore draw the receiver to erroneous locations.

¾Saltwater – Saltwater affects conductivity and can contribute to signal degradation. Before drilling in saltwater or brackish water, conduct a range test in the salt or brackish water to determine the amount of signal loss (see “Transmitter Salt Water Range Test” in the Operational Tests Section). Depth error will be increased and roll/pitch range will be reduced. A 2-point calibration can help reduce the error (see “2-Point Calibration Procedure” in the Receiver Section).

¾Conductive earth – Drilling through formations with high metal ore content can degrade the trans- mitter’s signal and cause depth errors and reduced roll/pitch range. Again, a 2-point calibration can be used to reduce the depth error (see “2-Point Calibration Procedure” in the Receiver Section).

To install your product accurately and safely, the location of every below-ground structure proximal to the intended borepath should be confirmed by potholing. This task is the first step in familiarizing yourself with the interference potentials near the intended borepath. The next step is to conduct an electrical interference/background noise check, as described below.

Electrical Interference/Background Noise Check

An electrical interference check will familiarize you with your site conditions and help determine potential locations along the borepath where the transmitter’s signal may encounter interference. Things that can cause interference include the following: traffic signal loops, cable TV, saltwater, microwave towers, utility data transmissions, power lines, fiber-trace lines, security systems, invisible (buried) dog fences, large metal objects, rebar, and cathodic protection.

DigiTrak® Mark III Operator’s Manual

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Contents Mark III Directional Drilling Locating System Trademarks Table of Contents Remote Display System Remote Telemetry License Limited Warranty Safety Precautions Vii RememberViii Dear CustomerBasic DigiTrak Equipment IntroductionDigiTrak Directional Drilling Locating System Basic DigiTrak Operation IntroductionTechnical Support 3000-00b-F Showing Display Window Icons ReceiverDigiTrak Receiver Side View DigiTrak Receiver Top ViewDisplay Window Icons ReceiverTo turn the receiver on Depth Measurement Units Receiver Battery Voltage LCD TestFirmware Version Remote Channel Setting On/OffClicking vs. Holding the Trigger Receiving the Transmitter’s SignalsTo turn the receiver off To change the channel Changing the Receiver’s Channel SettingTo change the measurement units Battery Status Display for Receiver and TransmitterReceiver Battery Status Voltage Remaining Changing the Depth Measurement Units English vs. MetricUltrasonic Function Temperature RangeUse of Ultrasonic Measurement To Determine Actual Depth Zeroing the Ultrasonics Calibrating the Receiver Determining 1-Point Calibration SignalDo not calibrate if To calibrate newer receivers Confirming Proper CalibrationReceiver Depth Antenna Plumb Line Using Depth Antenna Plumb Line to Mark Locate PointsSeries Firmware Functions Finding Firmware VersionRunning Time Meter Display Procedure for Observing the Predicted DepthDigiTrak Transmitter TransmitterHow a Transmitter Works BatteriesAntenna Index Slot Back FrontTransmitter Temperature DisplayBattery Status Display Temperature OverheatVerifying Proper Fit of Transmitter in Housing Sleep Mode Automatic ShutoffHow Transmitter Should Fit in Housing Front End Cap of Transmitter Showing Temp Dot and Index Slot To install a transmitter in the housingTips for drilling with a sensitive-pitch transmitter Locating the TransmitterSensitive-Pitch Transmitters Transmitter as an InclinometerRange Type Rating SpecificationsModel Type Length Signal Battery Temp Color Transmitter Serial NumbersRemote Display Unit Remote Display SystemTransmitter Temperature and Battery Status On/Off and Setting the ChannelRemote Display Using DigiTrak Receiver for Remote Steering Setting up DigiTrak Receiver For Remote SteeringRemote Steering ~ I5 DataLog CapabilityDigiTrak Battery Charger Battery ChargerBattery Charger Control Panel Battery ChargerCharging a Battery Battery IsSetup for Discharging a Battery Manually Conditioning a Battery in the ChargerConditioning a Battery Manually Indicator Lights and Meanings3000-00f-F System Operating Instructions Start-up ProcedureShutdown Procedure Moisture and Temperature AvoidanceGeneral Maintenance Optimal Operating TemperaturesSystem Operation Electrical Interference/Background Noise Check Signal InterferenceSuggestions for Dealing with Interference Signal InterferenceSelf-Test for Mark III Receivers Operational TestsReceiver Balance Check Receiver Gain Test Operational TestsTransmitter Tests Transmitter Distance Color Transmitter Signal Strength ValuesCurrent Draw Test Transmitter Salt Water Range TestTransmitter Model Average Current mA Transmitter Battery Tests 3000-00i-F Locate Points Fnlp & Rnlp and Locate Line PLL Locating ModeLocating Mode Trigger Held LocatingHandling the Receiver LocatingSide View Finding the Rear Negative Locate Point Rnlp from the Drill Using Plus/Minus Indicators for LocatingUsing Plus/Minus +/- Indicators for Locating Locating the Transmitter from the DrillPlus Changes To Minus Drill Fine Tuning Rnlp Location Walking Toward LeftFinding the Positive Locate Line PLL from the Drill Finding the Front Negative Locate Point Fnlp from the Drill Fine Tuning Fnlp Walking Toward LeftFinding the Transmitter and Its Depth Method for Confirming Position Locating the Transmitter from the FrontMethod for Confirming Position Locating the Transmitter from the FrontOff-Track Locating Locating on the FlyOff-Track Locating Four-Turn Technique Splitting the Front and Rear Negative Locate PointsTo find the Fnlp or the Rnlp Pitch Divider Calculating Depth Based on Distance Between Fnlp & RnlpCalculating Depth from Pitch Running off Pitch or Calculating Depth from PitchElliptical Shape of Transmitter Signal Field Transmitter’s Signal ShapeAntenna Configuration Signal ReceptionPositive Locate Line Above Transmitter Front and Rear Negative Locate PointsOrientation of Field Lines with Respect to Antennas 3000-00j-F DigiTrak Cable Transmitter System Cable Transmitter SystemLabel Indicating Cable-Ready Remote Display Cable TransmitterCable Transmitter Power Supply Connected to Remote Display Power SupplyCable Transmitter Adding Batteries in Series Remote Display with Cable Transmitter CapabilityOperation Viewing the Cable System Battery StatusProblem/Concern Causes/Solutions Section to Consult TroubleshootingTroubleshooting Troubleshooting Troubleshooting Troubleshooting 3000-00l-F Glossary Glossary Set the Ultrasonics Start-up = Power-up = Boot-upRemote Display RollUltrasonic Transducers Ultrasonic FunctionAppendix Percent Depth Increase 100 AppendixPercent of Grade to Degree Conversions Pitch Transmitters Percent Degree Degree to Percent of Grade Conversions Pitch Transmitters Degrees Percent 10.0 Calculating Depth Based on Distance Between Fnlp and Rnlp 3000-00n-F Remote Telemetry License 3000-00o-F Limited Warranty Warranty Claim Procedures
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