temperature on lead 190 fig9 is greater than 5 u00b0 f if so the constant k p is set equal to zero in step 204 if not the routine simply proceeds to step 206 where a new loading percent value is calculated as described by the equation in step 206 of fig1 if the load percent is greater than 100 step 208 then the load percent is set equal to 100 at step 210 if the load percent is not greater than 100 but is less than 0 step 212 the load percent is set equal to 0 at step 214 if the load percent is between the 0 and 100 limits the load percent is set equal to the new load percent at step 216 the variable duty cycle control signal generated by the controller can take several forms fig1 and 13 give two examples fig1 shows the variable duty cycle signal in which the duty cycle varies but the frequency remains constant in fig1 note that the cycle time indicated by hash marks 220 are equally spaced by comparison fig1 illustrates the variable duty cycle signal wherein the frequency is also varied in fig1 note that the hash marks 220 are not equally spaced rather the waveform exhibits regions of constant frequency regions of increasing frequency and regions of decreasing frequency the variable frequency illustrated in fig1 is the result of the adaptive modulation of the cycle time t cyc fig1 graphically shows the benefits that the control system of the invention has in maintaining tighter temperature control and higher suction pressure with improved system efficiency note how the.