The LET-1000-RD relay testing set has been designed to optimize the tests
required to check the sensitivity of electronic and electromechanical overload
relays and their response on the corresponding I/t curve. A combination of
different equipment sets has traditionally been used to run this type of test, with
consequent loss of time and possibility of error. The LET-1000-RD contains all
the systems required of such tests in a single unit of small size and weight and
can easily be handled by two people
Having determined the current range required, select the output from those available (250, 500, 1000A) and connect the tested receiver between the 0 terminal and the target terminal using cables of appropriate section for the current used. The operator should ensure that the terminals are properly tightened particularly in the higher fields, in order to avoid loss of power and undue heating.