Abstract: Sheathing for a resistance-tape level sensor which provides a multiplicity of enclosing envelopes for guarding the critical inner electrical sensing element, and multiple venting paths for respiration and pressure-equalization of chambers formed by the separate envelopes.

Abstract: A mounting head for a resistance tape level sensor is provided which includes a cylindrical outer shell enclosing deformable elastomeric elements surrounding and supporting certain elements of the sensor and clamped to provide high internal compressive forces for sealing all leakage paths.

Abstract: A distributed resistance material level sensor which is sensitive to actuation pressure of the material in which the sensor is immersed, and ruggedized to provide protection of the sensor by forces encountered during handling and during use. The sensor includes an elongated strip having sensitive front and back surfaces and respective insensitive edges extending along the length of the sensor. An elongated protective element is provided on each edge of the sensor, the element being retained on a respective insensitive edge and having a cross-sectional extent to provide mechanical contact and abrasion protection.

Abstract: For use with a resistance level and temperature sensor, operative to provide a measure of the level and temperature of a fluent material, a readout and alarm system operative to provide a numerical readout of material level and temperature as well as visual and audible indications of alarm conditions. The system is contained within a portable housing which can be employed in hostile environments and which can provide intrinsically safe operation in explosive atmospheres.