goods in rotating inner drum 22 since accelerometer 100 is reference point independent it will not be damaged by the excursion experience by the flexibly supported outer housing 13 as would the previously described vibration detection means in the prior art in this embodiment the accelerometer 100 is mounted on door 28 on the front of outer housing 13 see fig3 because in this system configuration the front end of outer housing 13 undergoes more movement relative to the back where more weight exists due to the motor 33 and all the other devices instrumental in rotating inner drum 22 accelerometer 100 is oriented to detect acceleration of outer housing 13 along the horizontal axis across the front of the housing however it could be placed anywhere on outer housing 13 to measure acceleration along any axis as best shown in fig4 a metal target 111 is mounted on periphery of pulley 54 and thus for rotation with the inner drum 22 driven by the pulley 54 more particularly the target is mounted so as to be angularly aligned with one of the ribs in this embodiment rib 1 as will be referred to hereinafter even though the target is angularly aligned with rib 1 the target could be angularly aligned with any point on inner drum 22 also a proximity switch 108 is mounted on proximity switch assembly 109 which is mounted on support arm 16a so that a pulse 106 see fig5 will be generated by proximity switch.