What safety checks should be used before the submersible pump is used?

1, Deep well submersible pump external circuit check: connect the submersible pump circuit, you should look at the power signal, and then closing. Such as water is slow and weak. Should be wired any two-phase change; if not on the water or water check, the submersible pump issued a "moo" sound and do not turn, should immediately stop checking. Check the order is: see if there is a fuse fuse fuse, poles lead to contact with bad, such as poor contact should be immediately removed to prevent the submersible pump running, burn the winding.
2, sealing inspection: mechanical seal box wear gap is too large, if not timely maintenance, water leakage caused by water leakage, breakdown winding, causing submersible pump burned. After the general work of 300h, the water sealing plug will be loosened to check. If the water or water and oil mixture is less than 25mL, the pump can still be used; if more than 25mL, should check the overall seal box grinding wear. If the grinding block damage, should have the appropriate technology and equipment manufacturers to repair. Usually can be used to inflate the pump pressure table to check the pump seal, inflatable pressure of 19.6kPa, for 10min, if the pressure gauge needle does not move, then as a good seal.
3, Insulation check: If the submersible pump itself leakage, after the water will cause the junction box between the leakage and the shell is not insulated. So should always check the submersible pump insulation resistance, generally should be more than 0.5MΩ, less than 0.5MΩ, submersible pump shall not be used.
4, the protection of the inspection: submersible pump protector trip coil burned, it lost the protection of the submersible submersible pump. The main reason for the tripping of the trip coil: First, the load is too large, such as well depth, water pipe bending, pump plug, bottom network plug, etc .; Second, the voltage is too low with submersible pumps.