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Spindle Speed Desviation. Fanuc 10M. Mori Seiki Mv55


Jan 20, 2020
I have a mori seiki mv50 with fanuc 10m system. After a parameter lost when I bought machine, I have some issues with spindle speed. Spindle driver is digital type. Spindle motor is AC type model 8. 6000 rpm configuration.
When I program M03S100, the speed is too fast as see. I also see spindle driver showed 700 rpm in their 7-segment led.
I tried with parameter 5613 “Compensation value for offset voltage of spindle speed analog output.”
Procedure says program M03S0, then calibrate 0V measuring at DA2 and 0V pins on spindle driver board.
When program M03S0 in MDI mode control turn on error red light but voltage is present on DA2 – 0V, so I enter a value in 5613 parameter and get 0.001V on DA2-0V test points. I think I did it ok.
Then procedure requires parameter 5614 “Data for gain adjustment of spindle speed analog output.” Data range is 700-1250.
According my maths 6000rpm = 10V. so 100rpm =0.167V. When M03S100 is programmed, the voltage is 1.139V and Spindle Driver shows 708 rpm. Spindle looks like 700 rpm but not 100 rpm as I program. Spindle Override is 100%.
Parameter information explain about Correct Voltage / Voltage Measured x800 as value of 5614. according my values 117 is the result, but data range start in 700.
From 0-700 as value of 5614 the spindle speed in driver is 708, from 701 to up the rpm is increasing.
As spindle driver is digital parameters F29=125 and F30=0.
Any suggestion about what is wrong or any other advice to check spindle speed parameter.?
On the other hand someone knows which is the maximun speed in low gear before gearbox changes to high gear? and what is the best parameter to configure 5621 or 5641?


Jan 5, 2014
Vancouver, WA. USA
Did you reload the PMC parameters (Timers, Counters, Data, KeepRelay)? Some of those affect the spindle operation.

Also, the MV55 has a 2 speed gear box in the head. When you command S100 the machine will be in low gear so the spindle motor will be running a higher RPM than the spindle speed.


Oct 10, 2009
Iirc my MV-65 had about a 6:1 reduction in low range. Low range maxed out at 1000 RPM. I know in high range 6000 RPM at the motor was 4500 at the spindle.