Hey all,
the Modbus commands that a VFD understands are listed and explained in the VFD manual in the chapter on Modbus protocol.
The spindle deceleration is a function of the VFD, set by a parameter (braking with internal or external braking chopper with or without additional resistor, vs. leave spindle coasting) and can be influenced by the size of an additional braking resistor (the less resistance, the more watts transformed into heat thus the faster stop, at same time the more is the resistor’s size). See VFD manual for braking resistor specification. Be sure to have temperature sensor and cooling fan in your VFD control cabinet, braking resistor can get very hot.
Stop mode “STO (Safe torque off)” is always leave spindle coasting.