S type platinum rhodium - 10 Platinum thermocouple on the leakage reason ( 1) On the furnace refractory at high temperature insulation fault, equipped with wire furnace furnace wall inserted with metal wire contact with thermocouple, thermocouple is easy to make furnace refractory at room temperature is a good insulating material. Resistance furnace lining with alumina refractory brick for the most part, its resistance value also significantly reduced with temperature rise. ( 2) Furnace silk and s-shaped platinum rhodium - 10 Platinum thermocouple contacts, platinum rhodium thermocouple protection tube is alumina ceramic tube, accidentally silk made separation insulation porcelain tube wear, under the high temperature insulation performance also want to reduce, cause leakage, after the leak to the thermocouple, so there is ac leakage on the thermocouple signals. S type platinum rhodium - 10 The platinum thermocouple on the leakage solution ( 1) Keep the thermocouple is not in contact with the refractory brick. ( 2) The thermocouple negative ground, eliminate the leakage on the thermocouple signal. ( 3) Add filter on the thermocouple output end device. ( 4) From the hot junction thermocouple leads to earth ground.