C12 speed jitter
- Thread starter woodentop
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Since no one else has responded... I'm not aware of any reports of the problem you're describing. I would recommend that you contact Festool UK for assistance and make use of the warranty coverage.
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- Jan 22, 2007
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First the quick answer, and then for those curious, the explanation why. Simply exercise the trigger by pulling and releasing it several times. This will clean the surface of the semiconductor resistor located inside the power trigger.
Unlike most other drills, where the full power of the motor passes through the power trigger, the C12 (and all EC-TEC drills) have only a small control signal pass through the trigger. This is good, because you are not putting a lot of power through a small space with a resistive circuit (creating a lot of heat). Inside the trigger is a small, solidstate variable resistor that a conductive rubber wiper moves across. As the wiper moves, it changes resistance, which controls how much power the controller sends to the motor.
If dust gets on the surface of the resistor, it changes the resistance between the resistor and the wiper. This isn't noticeable at higher speeds because the resistance is already very low and the dust is a parallel resistance. At low speeds, this can be more noticeable.
Moving the wiper repeatedly across the glassy-smooth surface of the semiconductor resistor cleans any debris or film off the surface.
Unlike most other drills, where the full power of the motor passes through the power trigger, the C12 (and all EC-TEC drills) have only a small control signal pass through the trigger. This is good, because you are not putting a lot of power through a small space with a resistive circuit (creating a lot of heat). Inside the trigger is a small, solidstate variable resistor that a conductive rubber wiper moves across. As the wiper moves, it changes resistance, which controls how much power the controller sends to the motor.
If dust gets on the surface of the resistor, it changes the resistance between the resistor and the wiper. This isn't noticeable at higher speeds because the resistance is already very low and the dust is a parallel resistance. At low speeds, this can be more noticeable.
Moving the wiper repeatedly across the glassy-smooth surface of the semiconductor resistor cleans any debris or film off the surface.
festoolviking
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- Jul 7, 2009
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Hi!
I've got the same problem with mine so you're not alone. I will take mine to my festool rep. so they can have a say about it and hopefully sort it out.
Good luck!
I've got the same problem with mine so you're not alone. I will take mine to my festool rep. so they can have a say about it and hopefully sort it out.
Good luck!
Deansocial
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- Mar 14, 2010
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- 2,110
by jitter you mean fluctuate? my t15 did that and it was faulty electronics then it did it again and same solution
festoolviking
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- Jul 7, 2009
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- 361
Hi!
Finally got around to send my C12 in for repair, hopefully they will contact me next week for a quote. I'll keep you updated on the verdict.
Festoolviking
Finally got around to send my C12 in for repair, hopefully they will contact me next week for a quote. I'll keep you updated on the verdict.
Festoolviking
festoolviking
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- Joined
- Jul 7, 2009
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- 361
I went and picked up my C12 today. They have changed the trigger on it and the jitter is gone. The good part about this story is that I got my cordless early 2008 and I didn't have to pay anything for the repair. So talk about extended warranty! Close on 4 years. That's one thing I like about Festool, good customer care.
Festoolviking
[smile]
Festoolviking
[smile]
