WHILE TESTING A SHOP-VAC, ELECTRICIAN HAD CHECKED ALL CONNECTION WITH THE MACHINE LOCKED OUT ANDCOULD FIND NO PROBLEM WITH IT. HE SUPPLIED POWERIT (110 VOLT) AND STARTED CHECKING CONNECTIONS WITH TEST INSTRUMENT. THE WEIGHT OF THE TEST PROBE CAUSE A LOOSE CONNECTION TO BE COMPLETED ALLOWING THE MOTOR TO RESTART. THE FINS CUT THE EE FINGER.