1. To determine if the heating tube is the correct power.
2. Determine the wiring mode of the heating pipe. It is a star or delta connection. The heating pipe of the star connection cannot be connected to a triangle and cannot be connected in the wrong way.
3. The new heating tube should be determined whether it is qualified. Judgment method: Use 500V megger to measure the quality of the heating tube. The insulation resistance of the lead wire of the heating tube to the outer casing should be greater than 1MΩ.
4. Replace a secondary leakage protection circuit breaker, and replace it with the original leakage protection circuit breaker parameters.
5. To solve the problem of voltage instability, the voltage is allowed to fluctuate by 10 ‰ When the voltage is too low, if the resistance of the heating tube is constant, the current flowing through is greater than 380V~, causing the heating tube to burn out.
6. After the replacement of the heating tube, you must use a 500V megohmmeter to measure the insulation resistance of the heating tube lead-out line to the outer casing (to the ground), the measured value must be greater than 1M Ω. For reference only.