ACT-400

ACT-400 is based on the same architecture as Acoem’s trusted Cube ™ 4G noise monitoring terminal and IEC 61672 Class 1 Fusion™ 4G sound level meter. By removing the instruments’ display screen and accessories, but retaining all the proven technology plus the robust, waterproof casing, Acoem has been able to keep cost to an absolute minimum.

The sensor acts as a push system monitoring point rather than a hand-held meter, without the need for an external microphone or cabinet. It is mains powered but also has a back-up battery powersource. No support is required, and it can be automatically and remotely configured. In case of loss of connection, you will be able to set up alarms warning you of this event, but data will continue to be logged with information and data stored on an internal SD card.

To simplify on-site installation, Fusion has a function for the automatic detection of a calibration acoustic source which lets you calibrate and adjust the instrument without doing anything more than switching on the device.

An integrated measurement-chain verification system also performs periodic checks automatically. Electrical verification tests the entire measurement chain, including the microphone by injecting an alternating sinusoidal load on the microphone’s terminals at the selected frequencies, at one or two levels. The principle is to read reference values and check the deviation with respect to other measured values over time.

Fusion incorporates a highly sophisticated event-detection filter system — from the simplest to the most complex configuration. You can define an event and set a trigger that can be programmed over a maximum of 24 time periods. All parameters (overall level, spectral level, sliding Leq, meteorological parameters, etc.) stored at the logging interval instantaneously can be used to define the trigger. Each event can be activated by day of the week and can trigger different actions — digital coding, recording of an audio signal (WAV), video recording (using an external camera) — triggering of a parallel recording with a faster logging interval, sending of a customised text message, etc.

With Fusion, you can interface with the VAISALA WXT536 (six sensors) and WXT532 (two sensors) stations. Acoem chose these two stations because neither features moving parts, averting the risk of mechanical malfunction due to freezing temperatures or wear.

The weather station and Fusion share a power supply with a 10-metre cable connecting the two units, giving you increased flexibility when installing the system. Meteorological data is stored on the Fusion system and transmitted in the same way as acoustic data (WiFi, 4G modem, USB cable, etc.). The logging interval for meteorological data is a multiple of the acoustic logging interval. Using the remote interface, you can view the wind speed and direction (and additional weather data) in real time.