ULD is USB Ultrasonic microphone for Android smartphones and tablets with driver and application for Compressed Air Leak detection and management with real leak cost calculation.

Benefits & Features

  • Fast Leak Detection
  • Immediate Flow and Cost estimation
  • CALMS Leak Management System Synchronization
  • FFT Graphical Leak detection
  • Data Export option (CSV)
  • Save energy costs on Leaks, Inappropriate uses & artificial demand
  • Save your time and improve the organization
  • Improve your environmental image
  • ISO 11011, Compressed Air Assessment compliant


The MEMS (Micro-Electro-Mechanical Systems) microphone is very sensitive, with a good signal/noise ratio and small form factor.


Connect the ULD sensor to your Android smartphone or tablet, and it will immediately be recognized as a new input. Additionally, you have to connect Bluetooth wireless headphone. With CALMS ULD Android software ULD sensor will be recognized and ready to find leaks. Next step is to log in to CALMS web service and sync data to start doing Leak Management.

See table for Android device compatibility.


ULD is factory set to work with CALMS ULD software. No field adjustment needed.

Description CALMS ULD
Sensor MEMS high sensitivity ultrasonic acoustic sensor
CPU Integrated micro-controller 32 bit
Type Digital, with high-quality low noise analog pre-amplification
Sampling rate 190 samples/second
Frequency range 96 kHz
Resolution 16 bit
Communication USB 2.0
Software ULD for Android ver.6 or higher with USB OTG *
Operating Range 0 – 45 C
Power supply USB 5Vdc
Size L 130 mm x W 18 mm
Weight 120 g
Materials Enclosure: ALU, Cable Entry ABS plastic, EPDM rubber
Phone Holder Yes (up to 5.5”)
Scope of supply ULD detector, holder, USB cable Type C or B, Bluetooth Headphones
EMC EC 2004/108/CE, 2006/95/CE
Class IP54
Approvals CE