Abstract: A multi-function sensor is disclosed for measuring the conditions within a container, such as fluid level, turbidity, temperature and pressure. The sensor incorporates a fluid level sensor module, a turbidity sensor module, a temperature sensor module and a pressure sensor module. The fluid level sensor module utilizes a plurality of thermocouple junctions grouped in pairs with the pairs being spaced along a line extending generally in the direction in which the liquid level may vary. The thermocouple junctions are connected in series and produce a signal indicative of the level along the sensor. Turbidity, temperature, and pressure sensor modules may also be incorporated in the multi-function sensor. Alternatively, a fluid flow rate sensor module may be included in place of the liquid level sensor module.

Abstract: A high temperature PTC device comprising a polymeric conductive composition that includes nylon-11 and a carbon-based particulate conductive filler has a switching temperature greater than 150.degree. C., preferably between about 160.degree. C. and 200.degree. C. The composition demonstrates a high PTC effect (at least 10.sup.3, and more typically 10.sup.4 to 10.sup.5 or greater) and a resistivity at 25.degree. C. of 100 .OMEGA.cm or less, preferably 10 .OMEGA.cm or less. High temperature PTC devices that comprise nylon-11 or nylon-12 compositions and that are manufactured by extrusion/lamination demonstrate good thermal and electrical stability compared with those manufactured by compression molding and do not require composition crosslinking for stability, although crosslinking may be used to further improve stability. The use of a high temperature solder for attaching electrical terminals to the device improves the PTC properties of the device.

Abstract: A motor overload protector or the like is disclosed in which a bimetal snap disc is centrally supported by a stud which is press fitted into a bore within the body. The stud is knurled to provide axially extending teeth having a root diameter at least substantially equal to the diameter of the body stud receiving bore prior to the insertion of the stud so that sufficient friction is provided to maintain the stud in the calibrated position. Additional locking is provided where necessary by forming the stud with annular ribs which interlock with a potting material applied after assembly of the stud within the body. The device is calibrated by maintaining the disc at the desired operating temperature as the stud is pressed into the body stud receiving bore until the disc operates.