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.

DescriptionCALMS ULD
SensorMEMS high sensitivity ultrasonic acoustic sensor
CPUIntegrated micro-controller 32 bit
TypeDigital, with high-quality low noise analog pre-amplification
Sampling rate190 samples/second
Frequency range96 kHz
Resolution16 bit
CommunicationUSB 2.0
SoftwareULD for Android ver.6 or higher with USB OTG *
Operating Range0 – 45 C
Power supplyUSB 5Vdc
SizeL 130 mm x W 18 mm
Weight120 g
MaterialsEnclosure: ALU, Cable Entry ABS plastic, EPDM rubber
Phone HolderYes (up to 5.5”)
Scope of supplyULD detector, holder, USB cable Type C or B, Bluetooth Headphones
EMCEC 2004/108/CE, 2006/95/CE