The blue ghost effect

[corngolem 0]

Turn off and unplug your printer, then move the extruder on one axis fast enough. The LED of the extruder and the LCD of the controller will light up !

I assume it is because the motors act as dynamos. Did you ever notice ?!

 

[kitwashere 1]

I have noticed this as well haha good name for it. I figured it probably wan't so good so I don't do it intentionally but it is kind of cool

 

[ian 32]

i was cleaning the rods with sowing maschine oil and spotted that in the dark... scary... ;-)

Ian

 

[codemaven 0]

Yeah, I've seen this and I find it very odd.... It indicates that there are no flyback diodes on the motors which is simply bad design. Motors should always have flyback diodes to prevent damage to the sensitive bits of silicon...

However, I thought that the motor controllers we use had integrated diodes on the chips so external ones should not be needed... And it's also strange that it's able to find a path all the way back to power up the LED on the TC amplifier board...

In any case, I wouldn't worry too much... Those motors can generate surprisingly large voltages across sensitive parts meant for 5v only.... But if there was a serious problem with it then we would have people complaining about blown electronics all the time. There must be enough resistances and protection in the circuit to prevent damage to the sensitive bits of silicone. I always move my head by hand and don't concern myself with it too much.... I've not had an issue yet nor have I heard of anyone damaging their electronics this way.

Cheers,

Troy.