【2025 Temperature Meters】Can one thermocouple be connected to multiple display instruments or DCS system cards?

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【2025 Temperature Meters】How to determine whether a temperature measurement system meets the technical requirements for process measurement: https://bbs.hcbbs.com/forum.php?mod=viewthread&tid=5696411&shareuid=172778

Even when thermocouples, thermal resistors, and bimetallic thermometers are of good quality, proper installation procedures are essential. To obtain as accurate measurement results as possible and minimize errors, it is crucial to pay attention to the depth at which these devices are inserted.

【2025 Temperature Instruments】Calculation and selection of thermometer sleeve strength per ASME PTC 19.3 TW-2016: https://bbs.hcbbs.com/forum.php?mod=viewthread&tid=5696410&shareuid=172778

①The insertion depth of the temperature sensor with a fixed threaded mounting is calculated as half the diameter of the pipe plus the size of the mounting boss for the sensor plus the thickness of the insulation layer. ◆ Thermocouples and thermal resistors have external sealing; taking the insulation layer thickness into account is necessary to ensure easy installation or removal without damaging the structure of the insulation layer. The common lengths for the mounting bosses of temperature sensors are 60 mm and 120 mm (they can also be manufactured to meet specific requirements), while the typical thickness of the insulation layer is 120 mm. ◆Bimetallic thermometers are hermetically sealed; the method for calculating the insertion depth is the same, but 30 mm should be subtracted from the size of the temperature sensor’s protrusion (this is related to the structure of the protrusion).

②The insertion depth of the temperature sensor installed on the fixed flange is calculated as half the pipe diameter plus the size of the flange connection pipe plus the thickness of the insulation layer

③For temperature sensors without fixed fixtures, with movable flanges or movable threads, the insertion depth must be adjusted by the user. For example, in the case of thermocouples used to measure temperature inside a furnace, the insertion depth is typically calculated as the actual length inserted into the furnace plus the thickness of the furnace body (including the thickness of the furnace walls) plus the thickness of the insulation layer.

①For different measurement media, the insertion depth of the temperature sensor varies. To ensure measurement accuracy, the sensitive part of the temperature sensor must be fully inserted into the medium being measured. The required immersion length for temperature sensors is generally as follows: ◆ When measuring gases, thermocouples should have an immersion length of more than 95 mm, while thermal resistors and bimetallic thermometers should have an immersion length of more than 115 mm. ◆When measuring liquids, thermocouples, thermal resistors, and bimetallic thermometers should all be larger than 46 mm. ◆The total insertion depth of the temperature sensor is: temperature sensor mounting boss + tube wall thickness + immersion length.

①For different measurement media, the insertion depth of the temperature sensor varies. To ensure measurement accuracy, the sensitive part of the temperature sensor must be fully inserted into the medium being measured. The required immersion length for temperature sensors is generally as follows: ◆ When measuring gases, thermocouples should have an immersion length of more than 95 mm, while thermal resistors and bimetallic thermometers should have an immersion length of more than 115 mm. ◆When measuring liquids, thermocouples, thermal resistors, and bimetallic thermometers should all be larger than 46 mm. ◆The total insertion depth of the temperature sensor is: temperature sensor mounting boss + tube wall thickness + immersion length.