Chamber pressure appts. probe with pressure dependent resistance - pref. with the probe resistances protected by silicone coating

摘要

Device for measuring pressure within an enclosure is based on one or more pressure sensitive resistance elements mounted on a probe and connected to a suitable meter. The resistance is made of a blend of conductive and non-conductive matl. and is connected across opposite sides of a Wheatstone bridge circuit. Over a pressure range of e.g. 0-400 bars responds with up to 20% signal level change, compared with about 2% for a conventional strain gauge. Pref. the probe resistances are protected from damage, moisture etc. by a coating of silicone resin. Suitable resistances are commercially available, e.g. hot-moulded type EB-RcR20 from Allen-Bradley.