Before the first power-on after magnesium oxide refilling, sintering and cooling must be completed, a cold-state test must be passed, and insulation must meet standards to prevent breakdown, short circuits, or equipment damage.
Essential preparations before the first power-on:
Confirming completion of sintering and cooling:
Sintering should be held at 800–1000℃ for 1–2 hours to ensure sufficient recrystallization of the grains; Natural cooling in the furnace to <200℃ should be used, followed by further cooling to room temperature (approximately 25℃) after removal from the furnace, taking 3–5 hours in total; Forced cooling such as water cooling or air cooling is strictly prohibited to avoid thermal stress cracking.
Perform cold-state performance testing and meet standards.
Insulation resistance test: Measured using a calibrated 2500V megohmmeter, result ≥ 500 MΩ (500V DC);
Withstand voltage test: Apply AC 2000V for 1 minute without breakdown or flashover;
The test environment should be dry (RH≤30%), eliminating surface leakage interference.
Check component physical condition:
The metal casing should be free of deformation, cracks, or bulges;
The lead terminals should be properly sealed using ceramic sealant or metal sealant, with a protection rating of IP65 or higher;
Lead wires should be securely crimped, with a contact resistance <0.03Ω, and free from oxidation or loosening.
Installation and environmental preparation:
Install the heating element correctly into the equipment, ensuring no mechanical stress;
The power supply line should be connected to a leakage current protection device and an overcurrent alarm system;
The surrounding environment should be clean and dry, avoiding dust or moisture. All preparations must be completed before power is supplied. Power must not be supplied if any step is not up to standard in order to prevent safety accidents.
