In the past, motor protection used fuses, overcurrent relays, thermal relays, thermostats, etc., but these methods have their own advantages and disadvantages. There are no absolutely reliable protection measures for variable load equipment such as power installations. Therefore, a variety of combinations must be adopted, which can be summarized in two aspects:
First, determine the increase or decrease of the motor input current;
Secondly, it is necessary to judge the heating of the motor itself.
Either way, the time margin given by the thermal capacity of the motor must be considered. Generally, the basic method of overload protection of refrigerator solenoid valve is: the overload protection of the continuous operation or jog operation of the motor, the use of temperature control devices; the resistance-rotation protection of the motor, the use of thermal protection; the use of fuse or fuse for short-circuit accidents Overcurrent protection.
In valve procurement, only clarifying specifications, types, pressures, and other practices that meet the procurement requirements are not perfect in the current market economy environment. For the sake of product competition, valve manufacturers all carry out different innovations under the unified valve design concept, thus forming their own corporate standards and product personality for intake solenoid valves. Therefore, it is necessary to make detailed technical requirements in the valve procurement process and reach an agreement with the manufacturer as an attachment to the valve procurement contract.