The isolation is to install the electric heating tube in the air so that the electric heating tube does not contact the refractory brick of the furnace wall, and the electric heating tube and the bracket are also insulated by insulation. This method can well prevent high temperature leakage interference.
The shielding is to wear the compensation wire of the electric heating tube in the iron tube or other metal for shielding. It can prevent electromagnetic interference and high-voltage electric field interference. When using this method, the iron pipe and shield should be well grounded, and the compensation wire should be twisted.
This method is for grounding treatment. There are two grounding forms: the first is the grounding of the reference end of the heating tube, and the second is the grounding of the measuring end of the heating tube. When use the first method, the output end of the electric heating tube (or compensation wire) is grounded through a sufficiently large capacitor (the larger the capacitor when conditions permit, the better). The second method is to ground the measuring end of the electric heating tube, that is, a metal wire is drawn out from the measuring end of the electric heating tube to ground. This method has a good preventive effect on high-temperature leakage interference.