Pixhawk settings RC3_MIN to below 1140

Hi all! I have a problem with my pixhawk :frowning: all ESCs beeping very rapidly when trying to take off, motors will not spin.
I founded a possible solution here:
diydrones.com/forum/topics/min-t … hen-trying
but I don’t known how to set [color=#BF0000]RC3_MIN to below 1140[/color]

I suppose it was in apmplanner2 : CONFIG/TUNING -> STANDARD PARAMS but I doesn’t found it…
Could anyone suggest where is the right place? :slight_smile: best regards