Test Method and Acceptance Rules
After assembly, each electric heater shall have its insulation resistance measured with a 500V megohmmeter at room temperature, which shall not be less than 50 MΩ. It shall withstand a dielectric strength test of 1500V for 1 minute without breakdown or flashover. Then, under rated working voltage in air, it shall be energized for 2-3 minutes without overheating, and the insulation resistance shall not be less than 0.5 MΩ, with leakage current not exceeding 0.5mA per kilowatt. Its power shall be checked to see if it meets the order requirements (deviation ±5%). After the test, check whether all parts of the electric heater are intact. Each electric heater shall be inspected and approved by the manufacturer's quality inspection department and accompanied by a certificate of conformity before shipment.
Usage Precautions
1. The control cabinet enclosure must be reliably grounded.
2. The phase and neutral wires between the bolt heater plug and the cabinet socket must be correctly connected; misconnection is strictly prohibited.
3. When installing or removing the bolt heater, the power switch must be turned off. For ZJK series control cabinets, the voltage adjustment and indication should be at the minimum position; for WQJ low-voltage control cabinets, voltage shifting under load is strictly prohibited.
4. The dedicated bolt heater needs to be manufactured according to the specific geometric dimensions of the bolt. When ordering, you need to provide:
A. Bolt outer diameter; B. Bolt hole diameter; C. Total bolt length
D. Bolt length; E. Information on the heating control cabinet used
