1. Check the connection line of the battery pack and the welding of the pole column for cracking or melting;
2. Check the rubber insulation sleeve for damage, and whether the pole and the live part are bare;
3. Check the battery pack for short circuit;
4. Check whether the box body is damaged or not, whether the special work bolt is lost or damaged, whether the cap seat is detached, and whether the battery sealing agent is cracked or leaked;
5. Check the leakage current once a week, the value of which shall not exceed the requirements of the following table;
6. Check if the power plug connector is in good condition;
7. Check the battery box and cover for serious deformation.
