ONICON, a Clearwater, FL-based manufacturer of energy measurement systems, has been acquired by Harbour Group. Founded in 1987, the company designs and manufactures measurement systems and flow-metering devices like BTU meters and turbine, electromagnetic, ultrasonic, thermal mass and vortex flow meters for water, steam, gas and compressed air applications. St. Louis-based Harbour Group invests in a number of industries, including manufacturing, distribution and specialty services.