In the majority of cases, the Series 710e NIR Moisture Gauge is installed over a conveyor belt, to make non-contacting measurements of the product flow. In some instances, however, at the desired point of measurement, the product is falling by gravity within an enclosed duct. In such cases the PowderVision Sampler facilitates measurement by capturing product in the falling stream, measuring it and then returning it to the product flow, without the need to remove product physically from the process.
This convenient approach also enables measurement signals to be fed to a PLC or SCADA to enable process control.
The PowderVision is a pneumatically activated device which requires a clean air supply; this obviates the need for moving mechanical components in the process. It comprises a stainless steel tube with industrial sapphire window and sample cup.
The PowderVision is installed horizontally and is held within an adjustable flange which is welded into the duct wall. The PowderVision is adjustable in order to ensure that the cup is positioned optimally within the falling stream of product.
The measurement cycle is as follows:
• the sample cup fills with product
• the gauge measures the product for the desired constituent(s) e.g.: Moisture
• the gauge records the product measurement and displays this on the HMI screen
• the sample is ejected from the cup by a jet of air
• the cycle recommences
The measurements are controlled from the 710e Gauge HMI which sends a signal to the air valve to activate the airjet to empty the sample cup. The measurement frequency is adjusted using the HMI, according to the rate of flow of the product in the duct.
For further information on NDC’s Powdervision Sampler, visit www.ndc.com/powdervision.