An overview of the electronic expansion valve drive controller; this controller can control the opening of two EEVs as a slave board. 
 Installation conditions
Avoid installing the motherboard in the following environments:
Relative humidity is greater than 90%;
Strong vibration and turbulence;
Exposure to continuous jets of water;
Exposure to corrosive pollutant gas (such as sulfur or ammonia, salt-alkali mixed smoke);
near high-energy electromagnetic fields and high-frequency oscillation sources (avoid installing control equipment near the transmitting antenna);
Direct exposure to sunlight;
in an environment where the temperature of the outside environment varies greatly;
There are flammable and flammable gases in the environment;
Exposure to dust (due to oxidation, corrosion will reduce the insulation of components);