ACM PLUS; Family of Current, Wave, & Tide Meters

Falmouth Scientific 3-Dimensional Acoustic Current Meter (ACM-PLUS) collects, outputs and stores instantaneous current velocity data in three dimensions along with 3-axis compass data, 2-axis tilt data, temperature data, and data from optional sensors, including an integrated CTD. The current velocity and tilt data can also be output and stored as vector averages over specified averaging intervals. The ACM-PLUS is configured and operated using ACMProPlus, a Microsoft Windows based software program included with the instrument. With ACMProPlus you can configure and deploy the instrument, acquire data in real time and download the data from the instrument’s memory. And the real-time data can be viewed on a real-time monitor or a dashboard.

The ACM-PLUS Instrument

The ACM-PLUS measures current velocity in the two horizontal dimensions and the vertical dimension using four acoustic transducers. Included inside the instrument’s housing is a 3-axis solid state compass for measuring the Earth’s magnetic field and a 2-axis solid state accelerometer for measuring tilt. A temperature sensor for measuring water temperature is located on the top end cap. Along with the optional CTD, the ACM-PLUS can optionally include two auxiliary analog input channels which interface with most DC output sensors, including dissolved oxygen, pH, chlorophyll, light transmission, and others. The ACM-PLUS can be powered from an external DC power supply or from an internal alkaline battery pack. Data can be acquired in real time in ASCII format through an RS-232 or RS-485 serial interface at baud rates up to 115200 bits/sec, or the instrument can be deployed and the data stored in its memory for later retrieval. A single bulkhead connector on the top end cap provides the RS-232 or RS-485 connection and inputs external power. The ACM-Plus is small in size and low in weight and has a depth rating of 200 meters. In addition, a 1.5-ton working strength 316 stainless steel frame is included with pad eyes on the top and bottom for securing to a mooring line, and zinc anodes are attached to the frame to provide cathodic protection. Optionally available is a 5-ton 316 stainless steel frame. In addition, a 7000-meter rated ACM-PLUS is optionally available.