Affordable and Accurate Site Surveys
Herzan offers a number of site survey tools to provide users with accurate measurements of their environmental noise. Below is a description of the technology behind these tools.
VA-2 VIBRATION ANALYZER
The VA-2 is manufactured by Table Stable in Switzerland. It consists of a sensitive measurement head and controller unit. The sensor is based on the same sensor technology contained within Table Stable’s active vibration control systems. It is made using a highly sensitive piezo accelerometer. Piezos convert kinetic energy into electrical energy. The sensor senses in X, Y, and Z simultaneously.
The geometry and mass of the VA-2 sensor head is very well characterized. All sensors have their own mechanical resonance, which limits their operable frequency range. Since it’s impossible for a sensor to provide accurate measurements over an unlimited frequency range, the manufacturer must decide on the frequency area of interest when designing the sensor. The linear frequency response range for the VA-2 is 2 to 1,000 Hz, which is the area of interest for building and structural vibrations, the critical range for site surveys.
The controller unit on the system provides the power supply and setting adjustments for the system. The control unit converts the electrical energy from the piezo sensor into an analog signal which can be viewed on an oscilloscope or signal analyzer. Since sensors can be used in environments with a broad spectrum of noise levels, the VA-2 controller features adjustable gain. This allows users to increase the sensitivity of the system when there are very low noise levels or decrease it when high noise levels are present. The controller also allows the user to switch between three display modes: acceleration, displacement, and velocity.
WAVECATCHER SITE SURVEY TOOL
The WaveCatcher site survey tool integrates all the crucial pieces needed for a site survey into one portable, easy-to-use site survey tool. Most sensors provide an analog signal as their output, which can only be viewed on an oscilloscope or FFT. These instruments are often unavailable or inconvenient to use. The analog signal must be converted to digital in order to be viewed using a computer. All WaveCatcher site survey tools include an analog to digital (A-to-D) conversion unit which is designed to be small but powerful. The A-to-D unit connects to any PC using a USB cable. The A-to-D unit can also power ICP sensors when connected to a computer.
The WaveCatcher software was internally developed by Herzan to be easy-to-use. It offers an intuitive graphical user interface (GUI) and broad control over the variables. Data can be viewed as a numerical data set or displayed graphically.
All the sensors offered with the WaveCatcher were selected with the precise requirements of site survey in mind. All components were chosen to be compact and easy-to-use. The complete system is shipped in a heavy-duty carrying case to provide excellent portability.