Correlator LD20HC

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  1. Products & Services
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  5. LD20HC

Correlator LD20HC

Advanced 2-in-1 measuring device for leakage location by means of correlation or acoustic leak detection

The correlator LD20 HC combines high-quality engineering "made in Germany" with the latest leak detection technology in pipelines or drinking water systems and hence can be recommended as the ideal standard equipment for water suppliers and measurement engineering service providers.

At leakage points water escapes under pressure and in doing so creates a discharge sound that is transported through the pipelines in both directions where it is ultimately detected by highly sensitive sensors, which can be mounted at readily accessible locations such as hydrants or valves.

The material and diameter of all pipes can be precisely specified

Seeing as the type of water pipe always influences the sound propagation, the material and diameter of all pipes can be specified in the LD20HC so as to examine up to 20 pipe sections in only one measuring process. The signal received is amplified and transmitted to the correlator via radio. The correlator permits 256 freely selectable filters to be applied to the signal.

Can also be used for acoustic leak and pipe detection

The LD20HC also allows the use of microphones available for the LD6000, for instance the LD6000 BMW.

Moreover, various structure-borne and ground-borne sound microphones can be connected to the LD20HC, for instance microphones available for the combined detector LD6000 such as the LD6000 BMW. A leak determined by way of correlation can be verified using a ground-borne sound microphone, but every other type of acoustic leak detection and pipe location is also possible.

Innovative smart mode with graphic and numeric smart indicator for faster leak detection

Thanks to the smart function (patent pending) the important aspects are immediately apparent: Potential points of leakage are displayed as bar indicator and the highest level denotes the leak. There is no quicker and easier way to detect leakages acoustically!

A few practical benefits:

  • Combination device for correlation measurements and acoustic leak detections
  • Advanced measuring technology with ultra-fast six-core processor in a robust aluminium housing
  • 64-bit three-point correlation
  • Frequency analysis (FFT)
  • Material and diameter of the pipe sections to be measured can be specified
  • Time-saving correlation measurements of up to 20 pipe segments in one run
  • Innovative smart function
    for a still quicker acoustic pinpoint
    leak detection (patent pending)
  • User-friendly navigation with dual keypad touchscreen control
  • Highly sensitive sound receivers
    and high-performance radio transmitters – amplified by more than 60,000 times
  • Connection for structure-borne
    and ground-borne sound microphones
LD20HC: Compact, easy handling, powerful functions
LD20HC: Delivered ready for use in a transport case
The LD20HC allows for quick, simple and precise correlation measurements

Standard scope of delivery of the correlator LD20HC

Standard scope of delivery of the LD20HC:

  • correlator LD20HC with two antennas and a shoulder strap
  • LD K – sound-protected headphones
  • charger
  • LD-TA – transmitter 1 incl. sound receiver, coloured red
  • LD-TB – transmitter 2 incl. sound receiver, coloured yellow
  • transport case for measuring device, LD-TA, LD-TB and accessories


Optionally available accessories:

  • LD-TC – transmitter 3 incl. sound receiver, coloured blue
  • LD20 MA – magnetic base antenna for correlator with amplification
  • LD20 MA+ – magnetic base antenna for correlator with amplification
    (4 dB gain)
  • LD20 Hydro – hydrophone without pressure gauge
  • LD20 Hydro UF – hydrophone adapter on DIN hydrant claw with 1-inch internal thread for assembly using hydrant wrench
  • LD6000 VK – connection cable for ground microphones
  • LD6000 BMW – ground microphone (with dead man's button) sheltered from the wind
  • LD6000 BM – universal microphone with magnetic adapter
  • LD6000 DA – tripod adapter
  • LD6000 VL – probe rod extension with tip
The LD20HC enables 64-bit FFT high-performance correlation at up to three measuring spots

Process advantages of correlation measurement with the LD20HC

Schematic correlation measurement with the LD20HC

Correlation is a computer-aided procedure by use of which very precise leak detections can be performed.

A particular sound emanates from every point of leakage, which spreads over the pipe and to hydrants, fittings or valves. The sound is registered at up to three contact measuring spots by the highly sensitive signal pick-ups and transferred to the correlator via the LD radio transmitters. From the time difference of these signals, the LD20HC – in due consideration of material, pipe diameter and length of the measured section – calculates the exact position of the leak.

While – particularly in case of long pipelines – leak detection using other electro-acoustic methods is often hardly feasible due to interference factors such as the weather, the pipe's installation depth or a high background noise, leaks can usually still be detected easily using correlation.


Korrelator LD20HC im Trotec Webshop zeigen

Korrelator LD20HC

Fortschrittliches 2-in-1-Messgerät zur Leckageerkennung per Korrelation oder akustischer Leckortung.

8,704.85 € inkl. MwSt. Nettopreis exkl. MwSt. anzeigen

jetzt kaufen

Technical data

Technical data
General information
  Article number
  Measuring principle Piezoceramic
Sensitivity >1000pC/g
  Min. measuring range [Hz] 0
  Max. measuring range [Hz] 5,000
  Frequency range 0–4000 Hz acoustic leak detection
  Measurement resolution geophone 0 – 99 digits (equivalent to dB)
  Measurement resolution correlation 5 cm for a measuring distance of 100 m
  Filter 256 high-pass and low-pass filters
  Amplification [dB] 120
  Input impedance [Ω] 1 MΩ
  Output impedance [Ω] <10 Ω
Data transmission (radio)
  Transmission frequency [MHz] 433/434 MHz
  Transmission power [mW] 500
  5.7" touch colour LCD
  Backlit display
Memory organisation
  Memory Up to 100 measurements for each operating mode
  2 x SMA antenna socket
  Bayonet sensor connection (IP65)
  3-pin headphone connection (IP65)
  4-pin charging socket (IP65)
  USB cable connection (IP65)
Device control
  Touch function
  Control dial
  Supported languages EN, EN, FR, IT, PT, PL, SE, TR, HR, SL, SK, CN
Housing design
Type of protection
Ambient conditions
  Operation - min. temperature [°C] -10
  Operation - max. temperature [°C] 55
  Storage - min. temperature [°C] -25
  Storage - max. temperature [°C] 65
Operating time
  > 10 h continuous operation
Power supply
  Battery type NiMH battery, 8.500 mAh
  Length (packaging excluded) [mm] 380
  Width (packaging excluded) [mm] 155
  Height (packaging excluded) [mm] 67
  (packaging excluded) [kg] 2.9
  (packaging included) [kg] 4.2
Standard scope of delivery
Standard scope of delivery
  Measuring device
  Shoulder strap for measuring device
  LD K - sound-protected headphones
  LD-TA – transmitter 1 incl. sound receiver, coloured red
  LD-TB – transmitter 2 incl. sound receiver, coloured yellow
  Transport case
  Operating manual
Ascertainable measured values and functions
Functions and features
  Correlation leakage location (automatic, manual)
  Acoustic leak detection (F&L, Smart)
  Automatic filter adjustment
  Automatic amplification
  Preference memory function for manual filter settings
  Sound level override protection

 standard equipment

 optionally available

 not available