digital motor employed at 40 the current flowing to the motor is checked at 41 it is determined whether the current flow meets an acceptable limit at 46 if the current flow is not acceptable the 34 no current 34 error count is located at 47 the error count is advanced by 1 to account for new 34 no current 34 error at 48 the new 34 no current 34 error count is loaded in the memory at 49 the acceptable error established in the romset program i e how many transient errors will be allowed before the movement of the system is terminated such as 50 or 100 this allows flexibility so the doctor can make a determination depending on the environment of the patient at 50 the new 34 no current 34 error count is checked and a determination is made regarding whether it is below the maximum established as too many errors at 52 if the error count is above the maximum number of allowable 34 no current 34 errors the system physically burns a fuse designated the 34 open 34 indicator to show that for some reason there has been 34 no current 34 to the motor when there should have been current more than a maximum number of established times possible causes of the 34 no current 34 condition could be an open circuit or extensive interference from an external electrical field at 50b if the error count is below the maximum number of allowable 34 no current 34 errors the system loops back prior to decrement on time count and the process is continued at 42 if the current flow is acceptable a delay is imposed to match the time use for a 34 no current 34 decision at 43 the on time count.