Higher millspeed on my QT10ATC

I bought an QT10ATC M/C T3 -86 a few mounths ago and was a little bit dissapointed at the mill speed.
My ST30ATC M/C T3 -88 has 3000rpm on the mill head but this QT10ATC only did 1500rpm.
That was a litle low for my normal operation, I soon found that there was 2 options when it was sold as new 1500rpm or 2500rpm and the only differents was a pulley and shorter belts.
I checked with Mazak but I think it was to expensive, so the solution was to buy standard pulleys.
Original pulleys was 69mm in diameter on motor and 130mm as secondary.
I changed to 79mm om motor and 89 as secondary. (Motor axle is 28mm and secondare axle is 35mm) and 3 SPZ260 belts.
That gave me a theoratical speed of 2508 rpm.


Next step was to masure the real speed.
I got 2547rpm mill spindle but machine still thinks it is 1500rpm


To get the correct speed the controler there is 2 parameters to set.
GR6 sets the ratio, the rpms on mill head at full motor speed.
A10 sets a speed limit if wanted.
So I set both to 2540 and now I have a mill speed at 2540rpm and I double checked at 100, 300, 1000, 1500, 2000, and 2500 rpm and the speed on the mill head is correct.

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