SubSurface - LD-18 Operating Instructions Training
The LD-18 Digital Water Leak Detector is primarily designed for water leak “pinpointing,” the term used to describe the task of finding the exact location directly over a leak in a pressurized water pipe:
The LD-18 has both Standard Accessories and Optional Accessories:
- Amplifier with LCD Display, Controls, and USB Connection (to PC Computers)
- Padded Case for Amplifier
- 40 inches Belt (50 inches and 60 inches Optional)
- Ground Microphone and Handswitch
- Magnet Base and Nutdriver
- Heavy-Duty ABS Plastic Carrying Case
- Aviation-Grade Stereo Headphones
- PC Software and USB Cable
- Sensor with Strong Magnet and 9.75 ft. Cable (to listen at valves and hydrants)
Controls and switches for the LD-18 digital amplifier:
Amplifier’s LCD Display screen for listening and pinpointing:
Adjustments in the field:
At the spot no. 1, do you hear the leak? If “Yes,” than the LD-18 hears the leak too. Hold the Mute Switch closed and let the LD-18 listen for 30 – 60 seconds or longer until the Minimum Noise Level becomes constant. Press the SAVE button while still holding the Mute Switch.
Each time the SAVE button is pressed (while the Mute Switch is closed), the Minimum Noise Level is recorded in the LD-18’s memory and a file number is assigned. Press FILE to see the File List, and press FILE again to see the GRAPH:
With the Minimum Noise Levels saved at 5 – 10 spots directly over the pipe, examine the GRAPH by pressing FILE twice:
The Minimum Noise Level at each spot is the actual leak sound, and where it reaches a peak is where the leak is pinpointed.
The Band Pass Filters (HI and LO Filters) and Notch Filters (Off, 50 Hz, 60 Hz) are used for removing extraneous continuous noises like AC hum (60 Hz in USA), motors, air conditioners, wind, and traffic. Extraneous noises can interfere with the LD-18’s ability to hear the leak sounds.
The Noise Reduction function removes intermittent noises like footsteps, passing cars, and dogs barking. Choose Lv.3 (3.0 sec.) to remove the longest lasting intermittent noises, up to 3.0 seconds long. Intermittent noises longer than 3.0 seconds cannot be removed.