Kapex - No Load Current Draw (Please Help)

deepcreek

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It's my understanding that the electronic circuitry in the Kapex uses a tiny amount of electricity all the time even when the motor is not running.  In electrician parlance, this is called a "no load current draw" or simply "no load draw".

I'm hoping someone with a clamp-on multimeter can measure the current of a Kapex plugged directly into a U.S. 110/120V wall receptacle (NOT through a CT) and tell me how many milliamps it is using with the motor OFF.

It would also be helpful to know how much current it uses with the lasers turned on and the motor OFF.

I am not interested in how much current the motor draws so please don't bother to test this as it is not needed.

I have been using a tool activated start switch for my vacuum that is being triggered by the Kapex while the motor is off.  It does not do this with any other tool.

Thanks for your help!
 
A clamp on meter won't work (at least my fluke doesn't) because you have to isolate the neutral from the hot. If you just clamp the power cable your getting both lines which cancel each other out, resulting in a zero reading.

I used my inline meter which resolves to 10 mA. No load current draw reading was 0.00 A. So it must be less than 10 mA.

Sorry for the long winded answer, hope that helps.
 
That makes sense about the clamp on.  I don't have one so I didn't think it all the way through before asking the question.

The manufacturer of my "smart switch" says that the Kapex causes false activations of the vacuum because the electronics are always drawing current.  I suppose the laser would also draw some current.  They are trying to determine where to set a higher threshold level.

My Kapex has worked fine with this switch for four years but now as soon as I plug it in the vacuum starts.  The switch works correctly with others tools.

If anyone else can SAFELY test their Kapex, please report back to me. 
 
Something sounds a little fishy here, and I think you are getting the runaround from this manufacturer. The off-state current on a Kapex should be in the micro amp range, or a couple milliamps at worst. It's very unusual for one of these devices to get triggered from an off-state current draw. It is more common to have a problem that they are set so high that they don't detect a small tool being turned on, such as a sander. Typically, the threshold is set well over an amp or two, and this is why they don't detect small tools. For a large motor driven tool like Kapex, they could set the threshold at 5 amps.

More likely, the switch is seeing some sort of noise on the electrical line that is confusing its sensing circuit.
 
I don't think the manufacturer is giving me the runaround.  I'm dealing with their technical expert on this issue.  My switch is well out of warranty and they still offered to send me a new one.

They said that there have been other reports of false start problems using their smart switch with the Kapex.  They theorize that the no load draw of the Kapex is greater than the tolerances of their device but want to determine what level so that they can consider a redesign.

I intend to test mine to determine the resting load but am hoping that others can provide comparative values to see if there is something unusual with my Kapex.  If so, I'll contact Festool tech support.

Again, it worked fine for four years before this started happening.  The smart switch still works fine with other tools.
 
Brice_Arnold said:
A clamp on meter won't work (at least my fluke doesn't) because you have to isolate the neutral from the hot. If you just clamp the power cable your getting both lines which cancel each other out, resulting in a zero reading.

I used my inline meter which resolves to 10 mA. No load current draw reading was 0.00 A. So it must be less than 10 mA.

Sorry for the long winded answer, hope that helps.
Their is a device you plug into the outlet and then plug the tool into it that separates the H&N.
 
I used a line splitter with the 10x loop.  I was seeing 0.0-0.1 on my meter with the saw plugged in.  So 0-10mA.  With the laser turned on it was 0.1-0.2 on the meter or 10-20mA.
 
I'm pulling this from my recollection of chasing this issue a couple years ago.

We had 3 different iVac units and the Kapex would turn on one of the three when plugged in but turned off. I measured 10-15mA with the unit turned off. The Makita would do the same on that iVac unit as soon as the Laser was turned on.

We just moved the iVac units around.
 
RKA said:
I used a line splitter with the 10x loop.  I was seeing 0.0-0.1 on my meter with the saw plugged in.  So 0-10mA.  With the laser turned on it was 0.1-0.2 on the meter or 10-20mA.

I also tested mine with a line splitter on the 10x loop.  I was seeing .10 to .11 (10 to 11 mA) on my meter with the saw plugged in.  With the laser turned on, it was .12 (12 mA).

neil
 
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