3M 2250M-iD, 2273M-iD manual Sweeping Active Induction Mode Locating, Passive Sweeps

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and metal pipes), but would require increased sweep distance separation between the transmitter and receiver.

Note: If nothing is plugged into the Output Jack [T-6] of the transmitter, the transmitter will automatically turn on the internal antennae, and the last frequency used (8 kHz (12 Watt transmitter only), 33 kHz or 200 kHz) will broadcast in induction mode.

The induction frequency can be changed by pressing the Frequency button on the transmitter. For best results, the receiver should be at least 25 feet (7.6 m) away from the transmitter to begin tracing the target path and have the gain set between 78-84% when starting the sweep. This is used to establish a baseline gain threshold prior to starting a sweep. When crossing a target pipe or cable, the bar graph will close and the signal strength and audio response will increase. Attempting to trace the target close to the transmitter may lead to false indications due to the receiver detecting the large magnetic field radiating from the transmitter.

B. Sweeping (Active) Induction Mode Locating

Sweeping an area with the 3M™ Dynatel™ Locator 2200M Series allows the location of multiple metallic cables and pipes buried in an area without direct connect or coupler access to the cable or pipe. This approach is effective before any excavation takes place. Note that when specific buried objects need to be identified, it's important to use the direct connect or coupler method for applying the signal. This will help limit the applied locate signal to a specific facility that provides more position and depth accuracy along with an effective identification. There are two main types of “no access” or “blind” Induction Sweeps;

Passive Sweeps: These require only the use of the Receiver with passive frequency detection capability. This method uses existing external signal sources, such as 60 Hz/50 Hz for electric power, 15 kHz to approximately 30 kHz for low frequency radio signals, 120 Hz / 100 Hz CPS impressed current Cathodic Protection signals and the less commonly occurring CATV signal of 31.25 kHz NTSC with CRT TV turned on.

Active Sweeps: These require both the Receiver and Transmitter with Induction capability. This method refers to using a 3M Dynatel transmitter as the signal source through induction, instead of relying on passive frequencies that may exist on the buried conductor or metal pipe. Active Induction allows for detecting buried cables and metal pipes in the absence of passive signals and at deep depths and short sections. 3M Dynatel transmitters provide a choice of induction frequencies and output power levels. Higher induction output power levels are needed for detecting deeper depths and longer ranges. The 2200M Series 3 Watt transmitters provides two induction frequencies: 33 kHz and 200 kHz. The 12 Watt transmitter provides three induction frequencies: 8 kHz, 33 kHz and 200 kHz. The 200 kHz frequency is commonly used for deeper cables/ pipes and the lower frequencies are used to give longer locate distances. The 8 kHz (low frequency) induction helps in locating shallow facilities, such as risers.

C. Passive Sweeps

Select Special (single) Peak (Spl Pk) mode on the receiver and then select the frequency (source; for example, power, LF, etc.) to be traced. Passive sweeps at power frequency will detect buried power cables and conductors carrying 60 Hz/50 Hz power signal in the

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Contents 3M Dynatel Contents Rev G Rev G Rev G Intended Use Safety InformationAbout This Manual Quick Start Transmitter Battery InstallationReceiver Battery Installation Service and Accessories Cleaning3M Dynatel Transmitter 2273 Keypad and Connector Definitions Maximum Transmitter Output Rechargeable BatteryDynatel 3M Dynatel Receiver 2250M Key Pad and Display Definitions3M Dynatel Receiver 2273M Key Pad and Display Definitions Main Menu Menu DisplaysRev G Rev G Setting the Receiver Clock Configuring The ReceiverSelect Depth Units Selecting a LanguageEnabling/Disabling Frequencies Menu 6 + More SK4 + Setup SK6 + More SK6d + Tone Freq SK6jCreating User Defined Frequencies Selecting Locating Audio Filtering Power Frequency InterferenceDirect Connect Method Buried Cables And Pipes Transmitter ConnectionsRev G Dyna-Coupler Method Induction Method Non-Sweeping Passive Induction Mode LocatingPassive Sweeps Sweeping Active Induction Mode LocatingOne-person Active Induction Mode Sweeps Transmitter Set-up Two-person Active Induction Mode SweepsLocate/OK 5 + Cable/Pipe SK + Mode SK + DirNull SK Toggle Locate/OK 5 + Cable/Pipe SK + Mode SK + Dir Pk SK ToggleReceiver Modes Directional Peak Dir PkSpecial Peak Spl Pk Locate/OK 5 + Cable/Pipe SK + Mode SK + Spl Pk SK ToggleLocate/OK 5 + Cable/Pipe SK + Mode SK + Ind Pk SK Toggle Expanded ModeDepth and Current Estimate Induction Peak Ind PkActive Frequencies Locating FrequenciesPassive Frequencies Power FrequenciesAuxiliary Frequencies Locating in Directional Peak Mode Rev G Determining ADP Depth Locating Active Duct Probes SondesTransmitter Setup Locating Buried Sheath Faults and Earth Return FaultsPinpointing the Buried Fault Green Band Locating 3M Electronic Markers 3M iD Markers Alert ModeEnabling/Disabling Marker Types Press Locate/OK Single Marker Locate3M iD Marker Depth Dual Marker LocatePassive 3M Electronic Marker Non-iD Depth Creating New Templates Creating/Editing Templates for 3M iD MarkersMenu 6 + Data/Templat SK2 + User Templat SK2c Rev G Editing Templates Writing 3M iD Markers Menu 6 + Write Mode SK1Press Start Write SK Modifying Marker Data to be Written Press Menu 6 + Write Mode SK1Rev G Reading 3M iD Markers Read History Reviewing Marker Read/Write HistoryMenu 6 + Data/Templat SK2 + Read History SK2a GPS Operation Capturing the GPS Coordinates Capture Mode / ModeWrite History SK Communicating with the GPS DevicePath Mapping with GPS Menu 6 + COM Setup SK3 + GISMenu 6 + Com SK3 + GIS SK or PDA SK Creating Trace TemplatesAdditional Applications Aerial Faults ToningCable Identification Connection DiagramsMenu 6 + More SK4 + Help SK8 Help ModeMenu 6 + More SK4 + Self Test SK7 Self Test Of ReceiverStandard Configurations Product Description And Optional AccessoriesProduct Description Direct Connect Cables Earth Contact FrameOptional 3M Accessories for 3M Dynatel Locators Specification Receiver SpecificationsDetection Depth 3M Non-iD Passive Mode can display a fault resistance up to 10M Ω Transmitter SpecificationsRechargeable Battery Information Environmental and Regulatory SpecificationsRev G Important Notice Electrical Markets Division
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