To enable proper control of a grinding circuit, it is necessary to have accurate, reliable information about key operating parameters. Two such parameters are flow rate and particle size. Slurry flow measurements in a minerals processing plant, and particularly on a hydrocyclone feed line, are challenging, making it difficult to obtain reliable and accurate flow readings. The array-based flow meters have proven to provide accurate and, due to their non-invasive implementation, reliable flow readings. This technology is truly unique (Baker 2016). Automated particle size measurements have been traditionally performed with automated samplers that obtain samples from the consolidated overflow of a cyclone battery and feed the slurry samples to ultrasonic, laser, or caliper-based particle sizers. These particle sizing systems have update rates of the order of minutes and uptimes that typically range from 20% to 80%. The new technology using an impact-based technique provides for a sampler-free system with four-second updates from each cyclone in a battery.