Control device for refrigerating equipment

A control device for refrigerating equipment having at least one compressor and one defrostable evaporator placed in a space to be refrigerated, said device comprising:

• first and second manual setting means for generating respective output voltage corresponding to the temperature to be selected for said space and to the number of work cycles corresponding to the humidity level to be obtained in said space, said second manual setting means controlling the number of on-off work cycles to be performed by said means compressor between defrost operations;
• first and second sensor means for respectively detecting the temperatures of said space and of said evaporator and for generating corresponding output voltages, which respectively control the on-off work cycles of the said compressor according to the space temperature and to the evaporator temperature;
• a first electronic control means for controlling the on-off work cycles of said compressor depending on the output voltages generated respectively by said first manual setting means, according to the temperature to be obtained in said space and by said first sensor means, according to the temperature detected in said space;
• a second electronic control means for controlling the on-off work cycles of said compressor between defrost operations, depending on the output voltages generated by said second manual setting means, according to the selected number of on-off work cycles to be performed by said compressor and by a counter means which counts the number of on-off work cycles performed by said compressor, said second electronic control means stopping said compressor when the number of on-off work cycles counted by said counter means is equal to the number selected by said second manual setting means;
• a heating means for heating said evaporator and defrosting it, said heating means being controlled by said second electronic control means so as to be switched off when said compressor is operating and switched on when said compressor is stopped;
• and a third electronic control means for controlling the re-start of said compressor depending on the output voltages which are respectively generated by said second sensor means and by at least one reference voltage generator having a fixed reference voltage corresponding to the end of the evaporator defrosting, said third electronic control means determining the re-start of said compressor when said evaporator has been heated by said heating means at a temperature corresponding to the end of its defrosting.