Specification and design of mechanical sampling devices relative to telemetering system requirements

Multichannel Sampling Devices, commonly known as commutators in the Telemetering field, are used in most major multichannel telemetering installations. They are generally used for the purpose of sampling the outputs of a plurality of thermocouples, strain gages or other primary transducers. Although it is sometimes possible to employ other methods of sequential switching, the most effective method at this time involves the use of the mechanical rotary type switches of relatively compact construction in which direct physical electrical contact is achieved. In addition to their use as primary or secondary multiplexing devices in instrumentation systems, they are sometimes employed for the purpose of calibration, programing drift compensation of DC amplifiers, fault indication and for many other purposes.