IEEE qualified switches for pressures to 8000 psig, Vacuum, Differential or Level Control; Temperature Switches from 30° F through 510° F (-32° C through 265° C), with watertight or explosionproof enclosures.
General Description
Pressure and temperature switches for Class 1E service are modified versions of the industrial ASCO TRI-POINT product line. Special features include radiation resistance and high-temperature construction. Class 1E switches are available only as factory assembled units consisting of a single switch and transducer assembly, factory set at operating points, and tested as a single unit before shipping from ASCO.
Applications
ASCO TRI-POINT pressure and temperature switches are available for safety-related (Class 1E) applications outside containment in nuclear power plants. They are also suitable for the less stringent balance-of-plant requirements.
Operation
Pressure Switches
When pressure is applied to the transducer it is converted into movement of the piston. The piston movement is then used to control the operation of the electrical snap action switch(es) in the switch unit.
Temperature Switches
Temperature sensed by the bulb creates an internal pressure within the transducer. This pressure is then converted into movement of the piston. This piston movement is then used to control the operation of the electrical snap-action switch(es) in the switch unit. Temperature transducers are
available in two constructions, a direct-mount or capillary and bulb construction. The direct-mount unit includes a 1/2"" NPT connection for direct mounting to the process. The capillary and bulb construction allows remote mounting from the process.
Qualification
The ASCO Qualification Specification (AQS-21623) hasbeen prepared in order to provide generic qualification of pressure and temperature switches. It is based on the suggestions and requirements of IEEE-323-1974-""IEEE Standard for Qualifying Class 1E Equipment for Nuclear Power Generating Stations"" and IEEE-344-1975-""IEEE Recommended Practices for Seismic Qualification of Class
1E Equipment for Nuclear Power Generating Stations.""
The current ASCO qualification reports are:
Interlock Korea, the power moving the world
