Cause Analysis: (1) Short circuit. (2) Short circuit between terminals in a thermocouple junction box. (3) The compensating wire is short-circuited due to insulation burnout. (4) The compensation wire does not match the thermocouple. (5) The polarity of the compensation wire and the thermocouple are reversed. (6) The insertion depth is not enough and the installation position is wrong. (7) The thermocouple cold junction temperature is too high. Approach: (1) If it is checked, it can be dried if it is caused by moisture; if it is due to poor insulation of porcelain tube, it should be replaced. (2) Open the junction box and clean the wiring board. (3) Re-insulate the short circuit or replace the new compensation wire. (4) Replace with the same type of compensation wire. (5) Reconnect correctly. (6) Change the installation position and insertion depth. (7) The connecting wire of the thermocouple is replaced with a compensating wire so that the cold end moves away from the high temperature area. B Thermal potential is larger than actual. Cause Analysis: (1) Compensation wire and thermocouple type do not match. (2) The insertion depth is not enough or the installation position is wrong. (3) The hot electrode deteriorates. (4) There is interference signal entering. (5) The reference temperature of the thermocouple is too high. Approach: (1) Replace the compensation wire of the same type. (2) Change the mounting position or insertion depth. (3) Replace the thermocouple. (4) Check the source of interference and eliminate it. (5) Adjust the reference temperature or make corrections. C, measuring instrument indicates instability, sometimes not, when the time is high. Cause Analysis: (1) Poor contact of the hot electrode at the terminal. (2) The thermocouple has intermittent short circuit or intermittent grounding. (3) The hot electrode has been broken or is not broken. (4) The thermocouple is not mounted securely and it will oscillate. (5) The compensation wire has grounding or intermittent short circuit. Approach: (1) Reconnect. (2) Take the thermocouple's hot electrode out of the protective tube to find the point of failure and eliminate it. (3) Replace the new electrode. (4) The installation is firm. (5) Find out the point of failure and eliminate it. D thermocouple potential error. Cause Analysis: (1) The hot electrode deteriorates. (2) The thermocouple is not properly installed and installed. (3) The surface area of ​​the thermocouple protection sleeve is too much. (4) Measuring circuit short circuit (thermocouple and compensation wire). (5) The thermocouple circuit is broken. (6) The terminal is loose. Approach: (1) Replace the thermocouple. (2) Change the installation position and installation method. (3) Clean up. (4) Replace the short circuit with insulation. (5) Find the broken line and reconnect it. (6) Tighten the terminal. 15A S20A military steel bar 30CrMnSiA Alloy Steel bar Military Steel Bar,military steel bar modification,15A S20A military steel bar,30CrMnSiA Alloy Steel bar SHANDONG LE REN SPECIAL STEEL CO., LTD. , https://www.sdbrightsteelbar.com
Fault phenomenon: A thermal potential is smaller than the actual value.