On the use of a capacitive diaphragm gauge for dust detection in next-step fusion devices

The technology underlying a ceramic capacitive diaphragm gauge (CDG) manometer has been investigated for use as a microbalance for measurement of dust accumulation in next-step fusion devices such as ITER. Initial trials have confirmed in principle the use of CDG devices as dust microbalances and both the gauge head and electronics have been adapted to address the environmental constraints. Remote electronics, capable of controlling the gauge at a distance of $30\mathrm{m}$ , have been developed and a prototype device has been tested in the laboratory, where a sensitivity of $500\mu \mathrm{g}∕{\mathrm{cm}}^2$ and dynamic range of at least ${10}^3$ were demonstrated. The work shows that this approach is a promising contender to measure dust accumulation in next-step fusion devices.