SPACE HEATER MONITORING DEVICE OF A CRANE FOR PREVENTING CONDENSATION GENERATED IN ELECTRIC EQUIPMENTS BY TEMPERATURE AND HUMIDITY CHANGES BY OPERATING EACH SPACE HEATER WHEN THE CRANE IS NOT USED

摘要

PURPOSE: A space heater monitoring device of a crane is provided to restrict short-circuit caused by insulation reduction of an electric equipments by monitoring a normal motion state of a space heater and to maximize the utilization of the crane by reducing failures of the crane. CONSTITUTION: A space heater monitoring device of a crane is composed of a current transformer(CT) for measuring the amount of the current put into each space heater(12) in the crane; a current control relay(CR) for checking an operation state of the crane and executing switch-controls by comparing the amount of the current measured by the current transformer with a predetermined reference current value; a first relay(R1) turned on/off by the controls of the current control relay; a second relay(R2) executing on/off operations according to on/off of the first relay; a timer(T1) for applying power according to on/off switching motions of the second relay after the predetermined time; and a warning lamp and a buzzer(11) for alarming an operator about a failure of the space heater by power fed according to the controls of the timer.