110v kapex slowing to a stop

[1Che1]

Hi guys, my 110v kapex slows to a stop when trying to cut mitres in hardwood. It does this both when on the extractor (ctl 26) and not. I never have it on a lead from the transformer. I know years ago this was a problem for 110v tools but did not think it would be a problem for festool. I also have the 110v Makita 1650w saw for 1st fix and it does not have this problem. Any help or thoughts?
Thanks

 

[joiner1970]

Snap

I've found mine works ok if it's direct into my 3.3kva transformer though and not through my midi

 

[ajones]

Chris

I would think that a 3.3kva transformer would be to small for the saw and dust extractor have you tried a 5.5kva  trany?

 

[joiner1970]

Chris

I would think that a 3.3kva transformer would be to small for the saw and dust extractor have you tried a 5.5kva  trany?

Yeah I've used it on a big 10kva one (I think it was 10 anyway) it does run ok direct off the tranny though. Just odd that the old Makita as the OP said works fine. I bet that's down to the speed control as the Makita doesn't have it

 

[ifit]

Mine is the same, you just have to let it get up to speed before cutting and ease off to let it build back up if it starts to slow down

 

[1Che1]

I tried to cut a mitre on a piece of oak 45mm x 225 with the kapex plugged straight into the transformer and it would not do it in one cut. This is the same problem a lot of 110v tools had back in the early 1990's not the year 2015! Really for the price of the saw you would think it would do what it says "cut wood"
Thanks for all your comments

 

[Phil Beckley]

Hi
With 110v you still need a 'clean' input to the transformer and output to the machine and as big a transformer as possible with a short run of cable that is in good condition. Enough power needs to reach the machine to run the extractor and the machine being used otherwise the power drop can effect the electronics and speed control.
rg
Phil

 

[1Che1]

Hi
With 110v you still need a 'clean' input to the transformer and output to the machine and as big a transformer as possible with a short run of cable that is in good condition. Enough power needs to reach the machine to run the extractor and the machine being used otherwise the power drop can effect the electronics and speed control.
Thx Phil, the input to the transformer was clean, no cable used just the one that comes on the kapex (which is only 2months old) also I tried this with the kapex on its own with no extractor. It still would not cut the oak clean in one go when trying to bevel cut, where as my Makita and my mates dewalt manged it fine (both have other issues though). I really like the kapex but this is a bad fault that needs fixing.
I have a 3.3kva transformer but I will try the 5 to see if this helps.
Thx again for everyone's replys

 

[Handyman Mike]

Sorry for going OT here, but could you satisfy an American's curiosity? Why would you be using 110V tools in the UK?

 

[Bohdan]

When you overload a transformer or approach its max rating the steel becomes magnetically saturated and this causes severe distortion to the waveform. This doesn't affect motors much but it is no longer "clean" and can have random oscillations which will upset and confuse the control electronics which are fitted to most festools.

 

[1Che1]

Sorry for going OT here, but could you satisfy an American's curiosity? Why would you be using 110V tools in the UK?

most building sites say you have to have it for safety reasons

 

[Phil Beckley]

When you overload a transformer or approach its max rating the steel becomes magnetically saturated and this causes severe distortion to the waveform. This doesn't affect motors much but it is no longer "clean" and can have random oscillations which will upset and confuse the control electronics which are fitted to most festools.

Thanks for posting this a cool way to explain the effects.
rg
Phil

 

[Phil Beckley]

Hi
With 110v you still need a 'clean' input to the transformer and output to the machine and as big a transformer as possible with a short run of cable that is in good condition. Enough power needs to reach the machine to run the extractor and the machine being used otherwise the power drop can effect the electronics and speed control.
Thx Phil, the input to the transformer was clean, no cable used just the one that comes on the kapex (which is only 2months old) also I tried this with the kapex on its own with no extractor. It still would not cut the oak clean in one go when trying to bevel cut, where as my Makita and my mates dewalt manged it fine (both have other issues though). I really like the kapex but this is a bad fault that needs fixing.
I have a 3.3kva transformer but I will try the 5 to see if this helps.

Going up to a 5+ should solve the issue, if not drop me a line.
rg
Phil
Thx again for everyone's replys

 

[Phil Beckley]

Sorry for going OT here, but could you satisfy an American's curiosity? Why would you be using 110V tools in the UK?

It also explains why not all of the Festool range is available in the U.K on 110v. A 110v needs a seperate electronic from the 230v machines along with a diffrent winding on the armature.
rg
Phil

 

[Ed Bray]

When you overload a transformer or approach its max rating the steel becomes magnetically saturated and this causes severe distortion to the waveform. This doesn't affect motors much but it is no longer "clean" and can have random oscillations which will upset and confuse the control electronics which are fitted to most festools.

110v in the UK is required to be used for commercial applications as a safety feature and was brought in to reduce the number of fatalities caused by electric shock. The 110v supply is derived from two 55 volt dual phase supplies (i.e. no neutral). This is because the risk of being killed by an electric shock is very greatly reduced with AC voltages of less than 60V. Obviously there will still a slight risk but nothing like the risk of fatality if shocked using a 240v single phase supply.

This means there is often a market for cheap used 110v power tools in the UK, although people should be aware that these have usually had a hard life (or have been stolen).

On the upside though, you can purchase 110v tools from the US (I have many times as they are typically cheaper for a given item and have a greater choice available), they run happily from a 110V Site Transformer albeit with a slightly lower speed due to the difference between the US 60hz and the UK 50hz.

 

[Handyman Mike]

...
On the upside though, you can purchase 110v tools from the US (I have many times as they are typically cheaper for a given item and have a greater choice available), they run happily from a 110V Site Transformer albeit with a slightly lower speed due to the difference between the US 60hz and the UK 50hz.

You've now got 100V single phase, if I understand this correctly. Does this still meets the safety requirements?

 

[Ed Bray]

...
On the upside though, you can purchase 110v tools from the US (I have many times as they are typically cheaper for a given item and have a greater choice available), they run happily from a 110V Site Transformer albeit with a slightly lower speed due to the difference between the US 60hz and the UK 50hz.

You've now got 100V single phase, if I understand this correctly. Does this still meets the safety requirements?

Nope, but then again neither do any of my 240V tools and as I am not a commercial user or contractor, simply a hobbyist I do not have the H&S at Work Act restrictions placed upon me that they have.

 

[Handyman Mike]

Thanks, all, for your replies on the voltage questions.

 

[ifit]

It would be nice to have a mod that bypasses the electronics in the kapex, it would then be a decent saw

 

[Trumpet]

...
On the upside though, you can purchase 110v tools from the US (I have many times as they are typically cheaper for a given item and have a greater choice available), they run happily from a 110V Site Transformer albeit with a slightly lower speed due to the difference between the US 60hz and the UK 50hz.

You've now got 100V single phase, if I understand this correctly. Does this still meets the safety requirements?

Nope, but then again neither do any of my 240V tools and as I am not a commercial user or contractor, simply a hobbyist I do not have the H&S at Work Act restrictions placed upon me that they have.

Low voltage  is defined as 48V or below I think and deemed safe - i.e.  won't result in a critical voltage across the heart under worst case conditions.

110V trannies are centre tapped with Earth, giving 55v-0V-55V, most likely fault condition is you are earthed and then get exposed to one of the lives resulting in 55V max, which is near enough technically intrinsically safe.