Low protection level: the valve motor for Denso is fully enclosed squirrel cage structure, short-time intermittent working system (10min) self-cooling type.According to the requirements of GB4942.1-85, the lowest protection grade is IP44, the highest protection grade is IP68.Valve operating conditions and different environments, the requirements of the protection level is also different.The low level of protection will cause the internal cavity of the motor to be damp or dust and other foreign matter invasion, and the insulation resistance value of the motor will decline and cause damage.

Improper packaging, transportation and storage: the package of electric valve should be rainproof, moisture-proof and dust-proof, and the package should be firm and reliable.Rainproof measures should be taken during transportation. After arriving at the site, the products should be stored in a ventilated and dry place, not in the open air.It is forbidden to debug or repair in rainy weather. After debugging, all fasteners should be tightened to ensure the tight and reliable seal of all electrical parts.

Electrical protection failure and poor quality of electrical components: the micro switch in the valve electric assembly is the key component of the control mechanism. When the valve exceeds the stroke position, the micro switch will cut off the power supply and play the role of overload protection.Most of the electric equipment manufacturers will stroke and torque protection in series together, when the excess stroke or excess torque, the micro switch in time to cut off the AC contactor coil control power, so as to cut off the main circuit of the motor.