Omega Engineering SW142-20-B Thermocouple Rotary Selector Switch, 2 Pole, 20 Position

 The Isothermal design of these rotary switches minimizes temperature gradients between the input and output thermocouple wiring.  This in turn minimizes errors in transmitting thermocouple signals due to the generation of a thermal emf at the wire junctions. The low resistant silver contacts also enables switching of temperature sensitive resistance devices such as RTDs and thermistors,

Insulation Resistance: 20 Mohm at 300 Vdc
Contact Resistance: 0.004 Ohm or less
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