What are the performance requirements of electric heating tubes
According to the relevant national standards of the institute, the electric heating tube has the following requirements:
1. Heating-up time: Under the test voltage, the time for the component to rise from the ambient temperature to the test temperature should not exceed 15min.
2 .Rated power deviation: Under the condition of sufficient heat, the deviation of the rated power of the component should not exceed the following specified range; for components with a rated power less than or equal to 100W: ±10%. For components with a rated power greater than 100W, +5% to -10% or 10W, whichever is greater.
3 .Leakage current: cold state leakage current and leakage current after water pressure and sealing test should not exceed 0.5mA, hot state leakage current at operating temperature should not exceed the calculated value in the formula, but the maximum does not exceed 5mA I=1/6 (tT×0.00001) I—thermal leakage current mA t—heating length mmT-operating temperature ℃ When multiple components are connected in series to the power supply, the leakage current test should be conducted with this group of components as a whole.
4. Insulation resistance: The cold insulation resistance should not be less than 50MΩ during the factory inspection. After long-term storage or use, the insulation resistance should not be less than the MΩ thermal insulation resistance at the working temperature should not be lower than the calculated value in the formula, but The minimum should not be less than 1MΩ R= "(10-0.015T)/t" ×0.001 R—thermal insulation resistance MΩ t—heating length mm T—working temperature ℃.
5. Insulation compressive strength: the component should be maintained for 1 min under the specified test conditions and test voltage without flashover and breakdown.
6. Ability to withstand power-off: The component should be able to withstand 2000 power-off tests under the specified test conditions without damage.
7. Overload capability: the component should withstand 30 cycles of overload test under the specified test conditions and input power without damage.
8. Heat resistance: The element should withstand 1000 cycles of heat resistance test under the specified test conditions and test voltage without damage.