Load cell performance evaluation: For weighing of tank content in the RECUMO project

Determination of batch mass or volume in the accountancy vessel of RECUMO is important for both process control and safeguards. A load cell based balance is a valid option to accurately and precisely measure the mass of a batch and is used in many nuclear facilities. SCK CEN bought three 30 kg capacity load cells of accuracy class C6 and mounted each of the load cells underneath a leg of a reactor frame. Over a period of 15 months, the set-up was tested regularly for accuracy, repeatability and linearity. Therefore, batch experiments with water, weighed on a reference balance, and experiments with calibration weights were performed. A preliminar absolute uncertainty of 1.2 g (1s) was found for the load cell set-up. Relative uncertainties of 0.11, 0.047 and 0.031 % were found for batch masses of 1.0, 2.5 and 4.0 kg, respectively. The load cell set-up was evaluated as accurate, precise and robust and will be used by SCK CEN as primary equipment for determination of batch mass in the accountancy vessel of RECUMO.