Victor problem

[Al Skierkiewicz]

Andy,
Sorry I didn't make it to the Sensor Expo, work and union business has kept me busy the last two weeks.
As you have stated, it is not uncommon for the lights on a Victor to come on when the motor is driven particularly when selected for braking mode. (This occurs even if the breaker is pulled.) Since that is one of the conditions and you are sure that the motor is not being turned then the other motor is the one that is back feeding. I will bet that the motors are cross wired, possibly in the M- leads or there is a high resistance connection from the two Victors back to battery common. I know that there was a lot of gear crud coming out of the transmissions at Nationals and that may have made it's way into anywhere as well.
Did the Victors fail as they were in Houston? i.e. one or more of the 12 power transistors exploding? My feeling is if only one blows it's case off or if three side by side are destroyed, there was something conductive in the controller. If transistors on opposite sides of the controller blow, then there may be short in the wiring or a defective brush assembly. (Remember that the new drills have notoriously bad brush parts and I have seen some where the brush holder(s) move out of alignment and touch the body of the motor bearing housing. If a wiring error caused something to come in on the motor leads, i.e. +12 volts to M- when the motor is directed to drive forward, you might find one or two transistors in a string fail and it would always be the same string.
As a last resort, check the +5 volt line at the RC. It may have failed and is high, causing failure of the PWM input. This is pretty unlikely though, unless a 12 volt source was backfeeding through the PWM cable to the RC. I wish I could have got a look when you were here.