1. The single-phase power cable of mobile electric machinery and hand-held power tools must use three-core soft rubber cable, and the three-phase power cable must use four-core rubber cable; When wiring, the cable jacket should be put into the terminal box of the equipment and fixed.
2. Check the following items before using power tools:
(1) The shell and handle have no crack and damage;
(2) The protection grounding wire or neutral wire is connected correctly and firmly;
(3) Cables or flexible wires are in good condition;
(4) The plug is intact;
(5) Switch operation is normal, flexible and without defect;
(6) The electrical protection device is intact;
(7) The mechanical protection device is in good condition;
(8) The rotating part is flexible.
3. The insulation resistance of a power tool should be measured regularly with a 500V megohm meter. If the insulation resistance between the live part and the shell cannot reach 2M ω, it must be repaired.
4. The electrical part of the power tool after maintenance, must be insulation resistance measurement and insulation withstand voltage test, test voltage is 380V, test time is 1 minute.
5. The electrical circuit connecting the electric machinery and tools should be equipped with a separate switch or socket, and equipped with leakage current action protector, metal shell should be connected to the ground; It is forbidden to connect more than one device at a time.
6. The rated leakage current of the current leakage protector shall not be greater than 30mA, and the action time shall not be greater than 0.1 seconds; The rated leakage operating voltage of voltage type leakage protector shall not be greater than 36V.
7. The operation switch of the electric machine and tools should be placed in the part accessible to the operator. When rest, off work or sudden power failure, should be cut off the power switch.
8. Wear insulating gloves or stand on insulating pads when using portable or mobile power tools; Do not hold wires or moving parts of tools when moving them.
9. When using class III insulated power tools on damp or acid-containing sites and in metal containers, reliable insulation measures must be taken and supervised by special personnel. The switch of power tools should be located within the reach of the guardian.
10. The disk plane of the magnetic sucker electric drill should be flat, clean and rustfree. Measures should be taken to prevent the drill body falling after the loss of power when sidetracking or backtracking.
11. When using electric spanner, the anti-torque fulcrum should be firmly pressed and the nut should be fastened before starting.