Description The 551 Advanced Underground Locator is an intuitive, all-in-one locating device to give you tools to locate lines in a variety of situations. The kit consists of two key components—Transmitter and Receiver—to apply and detect signal, respectively, onto buried metallic lines such as:...
Display Indicators Transmitter 23. Signal Current Meter 25. Frequency (kHz) 24. Induction Mode 26. Numerical Display 27. Low Battery Receiver 28. Signal Reception Meter 32. Frequency (kHz) 29. Induction Frequency 33. Passive AC 30. 45-Degree Angle 34. Numerical Display 31. Peak/Null 35.
Performance may be impaired if signal is low. Signal Application Methods There are three methods of applying signal with the 551 Transmitter: Direct Connection (1.75 kHz + 33 kHz Simultaneously) Inductive Coupler Clamp (33 kHz Only)
For locating in general, it is best to use Direct Connection where possible to apply a strong, isolated signal to a line. With the 551 Transmitter, it is even more beneficial to Directly Connect in that Dual Frequencies can be simultaneously applied.
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Ideal placement of the Ground Stake is 2-3 feet off to the side of the path of the buried line where the line enters the ground. For unshielded multi-conductor cables, attach directly to all the conductors (fig. 2) for the strongest signal and to avoid applying the Transmitter’s voltage across any devices that remain connected, for example “2-Wire”...
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the Ground Stake and the jumper can be extended to the indoor point of connection to the line. Once connection is achieved, activate the Transmitter by briefly holding down the Power Button. Observe the Transmitter’s Signal Current Meter at the top of the display and increase the Output Level* (Up Button) until a mid-range reading (30% to 70%) is achieved.
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“Signal Frequencies” section for more information. Dual Simultaneous Frequencies By default, the 551 Transmitter sends both 1.75 kHz and 33 kHz signals through the leads. When directly connected in Dual Frequency Mode, you can switch between 1.75 kHz and 33 kHz on the Receiver to select the better performing frequency for the given situation.
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Dual Mode (fig. 5). You may wish to select a Single Frequency for a mild-to- moderate improvement in battery efficiency on the Transmitter if you only plan to use one frequency, or because you have two 551 Transmitters and wish to transmit individual frequencies to two separate lines and identify/track them separately.
Inductive Clamp – (33 kHz Only) Figure 6. Inductive Clamp If Direct Connection points are inaccessible or the line cannot be disconnected or de-energized to allow for Direct Connection, using the Inductive Coupler Clamp is another effective method of applying a signal (fig. 6). Remove the alligator clips from the leads and plug the leads directly into the Inductive Clamp.
Transmitter Induction – (133 kHz) When buried lines are inaccessible via Direct Connection or for access with the Inductive Clamp, the Transmitter’s Induction Mode can be used to broadcast a 133 kHz signal from the Transmitter’s integrated Inductive Antenna onto lines below. Place the Transmitter on the ground above the line according to the orientation depicted to the left of the Transmitter’s display (fig.
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Grounding for Inductive Coupling The line must have grounding on either side of where the Inductive Clamp or Transmitter Induction is utilized—either directly (shield bonded to ground, ground wire bonded to ground, etc.) or capacitively (buried in the ground for some distance). Figure 8.
Receiver Passive Mode The 551 Receiver will detect live AC current when in Passive Mode, the default “frequency” when first turning on the Receiver. A signal from the Transmitter is not required for tracing lines in Passive Mode; it detects the 50 Hz or 60 Hz Alternating Current* flowing through the line (fig.
Digital Mode By default, Passive detection starts in “digital mode.” Where 50 or 60 Hz electrical power hum harmonics are detected, a synthesized buzz is generated in proportion to make this potentially hazardous signal more prominent. Analog Mode Press and hold the “f” button on the Receiver in Passive Mode until “An” appears on the display;...
(crosstalk). 133 kHz This frequency is only used with the 551 Transmitter’s Induction Mode. The highest of the Receiver’s available frequencies, 133 kHz is easiest to induce with the compact internal antenna.
This can be useful for quickly tracking a cable path as it is intuitive and simple to follow. Be advised that the orientation of the tip of the Receiver also determines how much signal is received: maximum signal is received when the handle is parallel above the line, while no signal will be received when the handle is perpendicular to the line.
Depth Triangulation Figure 12. Depth Triangulation To determine the depth of the line, use Null Mode. Hold the Receiver with the tip pointed vertically downwards and mark the ground directly over the path. Turn the Receiver sideways to the path and tip it 45 degrees. When close to 45 degrees, the “45-degree”...
IntelliTrack noise rejection technology offers signal clarity in noisy environments. This mode significantly improves tracing lines near AC interference, particularly effective when tracing 1.75 kHz. IntelliTrack is available on the 551 Receiver in 1.75kHz, 33 kHz or 133 kHz frequency modes.
Frequencies Reference Chart Signal Electrical Need for Overcome Frequency Range Induction “Bleed” Interference Ground Resistance ↑High ↓Low ↑High ↑High ↓Low ↓Low High ↓Low ↑High ↓Low ↓Low ↑High ↑High SIMULTANEOUS Low Frequency: 100Hz – 8 kHz Medium Frequency: 8 kHz-65 kHz High Frequency: 65 kHz-500 kHz Best for longer cables ...
Regulatory Compliance This device complies with part 15 of the FCC Rules. Operation is subject to the following two conditions: (1) This device may not cause harmful interference, and (2) this device must accept any interference received, including interference that may cause undesired operation.
Maintenance Transmitter Battery Replacement 1. Turn off the unit. 2. Disconnect any leads. 3. Loosen thumbscrews. 4. Remove the battery cover. 5. Replace the batteries (observing the polarity indications). 6. Replace the battery cover starting with the bottom and hinging down the top. 7.
Unit Test Transmitter/Leads Test 1. Turn on the Transmitter making sure that the ends of the leads are not clipped together. The Signal Current Meter should be at one bar. A higher reading is likely a problem with the internal circuitry and requires repair. 2.
Field Test 1. Lay a wire at least 25 feet in length on the ground outside. 2. Strip the far end of the wire and wrap the end around a screwdriver/ground stake ensuring metal-to-metal contact between the wire and the ground stake.
Warranty Tempo Communications Inc. warrants to the original purchaser of these goods for use that these products will be free from defects in workmanship and material for one year. This warranty is subject to the same terms and conditions contained in Tempo Communications Inc.’s standard one-year limited warranty.
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