With high deceleration programmed, multiple axis can generate overvoltage during rapid braking -- read that as reduce the accel/decel.
If it is a 2/3 axis move the regeneration can be an issue.
The VSD manual states you can use a single braking resistor shared between drives, using the 4th channel if you only use 3 phase motors.
I have not found the information about how to use a shared resistor.
I have been working on a 5 axis machine with six drives for the past 7 weeks.
It has had an auto transformer (4KW) added to reduce the voltage down to about 155v and now has no problems.
The documentation on the Granite drives is rather short, and leaves a lot of guesswork to get it right.
The GDTOOL is rather pedantic about the undocumented reasons for logging on and off, and it is difficult to figure how to get repeatable results.
Rather painful, with 6 big motors to tune, and once the GDtool has had a go the USB, the smoothstepper gets confused -- OMR needed. One More Reboot!
Using to vdepi boards, there is no provision to parallel the estop signals.
This means only one breakout board can use pin 10.
My solution, and a valid one, because the estop is diode orred, is to connect the pin 10's on ports 1 and 2. (with a soldered link - yuk)
I have gone for 100% opto isolation on this rebuild and now reliable, no USB errors is the result.
Back to the original question...
The above led resistor calculations are valid. Use a big value >= 33K and be satisfied with dim leds. 10Ks will cook.
By the way, this machine is 12 x 5 x 2 (XYZ + 2 axis fancy head) and that is meters! You can park 6 fork lifts IN the machine. -- Lots of fun.
Super X3. 3600rpm. Sheridan 6"x24" Lathe + more. Three ways to fix things: The right way, the other way, and maybe your way, which is possibly a faster wrong way.