New Kapex on a CT26 in the US - minimum power requirements and circuit capacity

[Paul K]

I'm sure that the specs indicate that a larger circuit would be appropriate for this configuration, but in the real world, particularly on a job site, normally you would on have a 15 amp circuit.

I am not on the jobsite, but in my world's smallest work closet, would a kapex plugged into a CT 26 and then into the wall, if they run without blowing the breaker, am I OK or do I risk damaging the motors, etc.? If they run, will they only run half speed if the power is insufficient? This is my first kapex and I am used to the scream of a typical miter saw, the kapex is much quieter and I am concerned that I am running at something less that top speed.

According to a call with my electrician, he says that the motors will pull full power through the circuit and if they don't trip the breaker I should be good to do, so long as we make sure that the breaker has not gone bad.

What say you? Absolutely must upgrade the wiring and circuit to a 20 amp or 30 amp circuit, or if it works, run it normally if it is not tripping the breaker. I cut some 8 quarter hard wood and it seemed to run OK, but the motor sound seems off to me, will go to the store and listen to theirs, I suppose.

Thanks for your help. If there is a thread on this topic that I missed, please let me know.

One last thing - I wasn't aware of all of the history and discussion of motor problems with the Kapex - have the prior issues been resolved with the current version being sold?

 

[ChuckS]

Yes, there've been discussions on the points you raised in this forum and the conclusions have always been that using the Kapex with the CT26 on a 15 amp outlet is absolutely fine.

And there have not been any "smoking" motor issues reported on the REB model.

 

[Cheese]

I've run a Kapex and a CT MINI on a 15A service for the last 10 years...so far so good.

 

[Vondawg]

On a mini and a 26 no problems

 

[pixelated]

My shop closet is on a 15A circuit, my CT26 + miter saw does fine, as others mentioned.

 

[DarrenM]

Timely thread as I just purchased a CT36 yesterday and had a similar question. The circuits in my shop are 20 amp so no issue with breakers tripping. But my new vac has a label beside the power outlet that says "3.7A maximum". I bought the CT36 at a Festool demo event and the rep said "it's just a CYI thing that Festool does in North America". I had intended to use that outlet to power my Kapex and occasionally a Bosch track saw so I could take advantage of the automatic switching. But obviously both of those tools draw well over 3.7 amps. The track saw in particular probably draws 12 amps or more under load.

Even if the CT36 outlet can safely handle that much power, it has to flow through 25 feet of cord, plus another 15 feet of track saw cord before it gets to the tool motor. Seems like there will be a lot of voltage drop over that length so maybe I should only use the CT36 for smaller tools like sanders?

Should I just get the Bluetooth remote and plug my heavier power tools into their own circuits instead of trying to run them off of the CT36 outlet?

 

[rmhinden]

Should be fine running off of the CT36 outlet. Remember that these are peak loads ("maximum"), these usually happen at startup. The CT36 is triggered after the track saw is started up, so you won't be getting both peak loads at the same time.

Bob

 

[tjbnwi]

Unscientific but gives you a little more information.



Tom

 

[Cheese]

Unscientific but gives you a little more information.



Tom

Interesting Tom thanks...

It seems the initial in-rush current is higher on the CT 22 as is the constant current draw. The CT 22 hovers around 21 amps while the CT 36 drops to the upper 19's. No big deal but interesting.

 

[Cheese]

Interesting Tom thanks...

It seems the initial in-rush current is higher on the CT 22 as is the constant current draw. The CT 22 hovers around 21 amps while the CT 36 drops to the upper 19's. No big deal but interesting.

OK, so now that makes sense. I assumed the current draw was the same on both CT's but I see the CT 22 is rated at 1200 watts while the CT 36 is rated at 1000 watts.

 

[DarrenM]

Thank you for sharing the video - very interesting indeed.

The video proves that connecting high current tools such as mitre saws or track saws does work (although a 20 amp circuit is certainly preferred).

But I do find it strange that Festool does NOT rate the dust extractors for this scenario in spite of what the Festool rep told me. In my manual for the CT36, it shows max power consumption for the dust extractor itself is 8.3 amps (1000 watts). Then it shows "Total Connected Load" max 12 amps (1440 watts). It confirms that by saying "Max Rating of Connected Power Tool" max 3.7 amps (440 watts). So that outlet is really only meant for smaller tools like sanders or maybe a small router.

I *think* there are 2 reasons they do this:

1. A 15 amp breaker should allow 15 amps continuously at room temperature. But they are derated to 80% (12 amps) when installed in a panel beside other breakers due to potential heating from the other breakers.
2. Because the cumulative length of the 25 foot CT power cord + the length of the saw power cord could easily result in excessive voltage drop at the tool. This is very hard on electric motors and should be avoided if possible.

For me I think I will get the Bluetooth module and remote for use with my Kapex and track saw and put them on their own circuit, separate from the CT. I'll use the CT outlet for my smaller power tools though.

 

[Cheese]

So, seeing as you're really getting into the fine points of this example, don't forget including the additional wire length from the main service breaker box to the actual outlet that you've plugged the CT into. It all adds up...a foot at a time.

 

[4nthony]

But I do find it strange that Festool does NOT rate the dust extractors for this scenario in spite of what the Festool rep told me. In my manual for the CT36, it shows max power consumption for the dust extractor itself is 8.3 amps (1000 watts). Then it shows "Total Connected Load" max 12 amps (1440 watts). It confirms that by saying "Max Rating of Connected Power Tool" max 3.7 amps (440 watts). So that outlet is really only meant for smaller tools like sanders or maybe a small router.

I *think* there are 2 reasons they do this:

1. A 15 amp breaker should allow 15 amps continuously at room temperature. But they are derated to 80% (12 amps) when installed in a panel beside other breakers due to potential heating from the other breakers.
2. Because the cumulative length of the 25 foot CT power cord + the length of the saw power cord could easily result in excessive voltage drop at the tool. This is very hard on electric motors and should be avoided if possible.

For me I think I will get the Bluetooth module and remote for use with my Kapex and track saw and put them on their own circuit, separate from the CT. I'll use the CT outlet for my smaller power tools though.

I see photos and videos of the Kapex plugged into CT's all the time but never gave it a second thought. Now that I have a Kapex, I noticed the difference in ratings.

In Festool's marketing videos, they show the BT remote connected to the hose. In the Festool Live videos, Sedge shows it plugged into a CT 48 with no remote. In the SedgeTool videos with the Kapex, there's no remote.







I wonder if a warranty claim on a CT has ever been denied due to excessive draw on the auto-on socket?

The safest option would be to use the remote but good to know most use it without and don't have any issues.

 

[demographic]

So, seeing as you're really getting into the fine points of this example, don't forget including the additional wire length from the main service breaker box to the actual outlet that you've plugged the CT into. It all adds up...a foot at a time.

A good point.
I'm a UK based site carpenter and have (amongst other Festool offerings) a TS55 and a CTM26 Cleantec extractor.
Although the UK household power is 230-240 volts, our site voltage is 110-115 through a stepdown transformer which usually have 16 amp sockets.
Thats all fine and good... usually. However, sometimes when we have a mass of cable laid out from the transformer to the tool and extractor they kind of fight for power.
As the saw has a soft start the extractor winds up, then the saw starts getting into its stride a d the extractor slows down yada yada yada.
Keeping short (ish) cable runs (seems OK on my 25 metre reel though) makes the problem go away.
Or running 32 amp sockets and cables upto the extractor then a 1 metre 32 plug down to a 16 amp socket then the extractor.

So, yeah. Keep an eye on those cable runs.

 

[ChuckS]

I used to have a CT26 and Kapex 120 used together on a 15a circuit. No issues of any kind for 8 yrs or so. Now, the Kapex is used with a shop vac on a 20A circuit after a minor shop power upgrade. I'm sure the CT will work with any Festool tools on any 15A circuit.