leonlai,
You can view the parameter values on the HIM while the drive is active. Unless there is some safety restriction preventing you from getting close to the drive while the motor is running, you shouldn't have to wait until it's off.
You are sort of repeating yourself without answering some of the important questions being asked. The first question was what is the Catalog Number of the PowerFlex 70 drive you are using? It is not always vital to give this info but it can be, depending on the specific issue at hand.
Next question - is the drive supposed to run in reverse ever? I would guess, as you've mentioned the motor is being used as a "flow actuator" that it is not. Also, because you only have it wired for Stop/Start and not Fwd/Rev. Either way, can you please confirm this? Also, if it is not normally commanded to run in reverse, can it actually turn in reverse of its own accord, as in freewheel.
The Flying Start feature - I would agree, if the motor cannot turn in the forward direction of its own free will, then you would be better off disabling this feature. However, if it can freewheel, or be restarted before coming to a standstill, then this feature is best left enabled. As jraef stated, it is not on by default, so "someone" would have had to have enabled it, if it is indeed already enabled.
A drive will normally start with a speed reference of 0Hz and then ramp up to the setpoint speed reference. This is fine when the motor is at a standstill. You have 0Hz and relatively low current at startup.
Where you have a motor that is already spinning, the initial 0Hz speed reference can act to brake the spinning motor, which can exert huge forces on the mechanics of the application. With 0Hz and initial rotation, larger currents are generated. This scenario is not good for the motor and its coupling and is also not good for the drive.
The Flying Start feature is designed to prevent the drive from issuing the normal 0Hz speed reference at startup when a motor is already spinning. The Flying Start can sweep in a positive and negative direction until it "finds" the motor i.e. matches its speed (Hz) and voltage (phase). Once they are synchronized, the drive can then command the motor to the speed reference and resume normal control.
By the way, another thing you have not mentioned so far is what and where is the speed reference coming from?
If your motor is reversing, while Flying Start is enabled, and you know the motor is never commanded for reverse, then the normal procedure where Flying Start is to be left enabled, is to set...
P190 [Motor Direction]= 2 "Reverse Disabled"
(The default is = 0 "Unipolar")
This means that the direction is no longer changeable from any source, including the Flying Start feature. It will now look for the spinning motor on a positive sweep only.
This configuration is based on the fact that you know you are not commanding a reverse direction, and you know that the motor application cannot freewheel in the reverse direction of its own free will, prior to startup.
That is one possibility here.
Once we know more on those parameters we'll have more to chew on.
Regards,
George
Here's a couple of shots of a PowerFlex 700 I just viewed the parameters on while running...
Regards,
George