JMC 220V Servos with Acorn

[suntravel]

I am using JMC 220V Servos as spindle drives and for axis drive

They are available from 200W to 3000W and all drivers have the same functions and can use the same wiring for Acorn.
Despite the fact in speed mode that they use -10V / +10V they can be wired to Acorns 0-10V output and take the VFD Direction Output for the direction change.

With Acorn 6 you have -10V / +10V for the spindles and do not need to connect to the VFD Direction Output

In Position mode they can be wired directly to the Headers.

They also have an output for ZRi Home and Inputs to switch them to different modes, like from speed to position ...

Price range is on the low side and delivers with complete 3m wiring and a DIY plug for the CNC that needs some fiddly soldering
One other advantage for me is they do not need a extra power supply, saves space and bucks.

Right now I have had no problems with the servos, easy to wire and easy to tune for my needs.

Finished the schematic for axis drive, will do the next days one for spindle drive.

My wiring is with a momentary switch to reset them in case of ALM or the need to powercycle for parameter setting









In the Zip is the schematic as PDF and DWG , all JMC manuals / selection guides and the XML file for the drive types to use with Acorn.

Uwe

[cnckeith]

great! thanks, looks promising. for the axis motors can you share a parameter list of only the parameters that were changed and their values from the factory default/reset settings?

[suntravel]

I write the parameter list and tuning process tomorrow.

Uwe

[suntravel]

Wiring as spindle drive:



How to setup as axis drive:

P03-09 set to 10000 pulse/rev according to Acorn ( Set Acorn to 400 kHz )

Bench test.

Install on the axis, drive in a middle position

run AF_J-L and record the measured moment of inertia ratio and write it in P01-04

P01-02 Autotunning in real time is by default 1 (easy mode)
P01-03 Real time automatic tuning rigidity is by default 13, increase one value at time till the servo starts to vibrate, then one value back.

Now the servo will work ok, but you can go deeper in tuning using the software and adjust everything manual for the smallest position following error.

How to setup as spindle drive:

P01-01 to 1: Speed control mode
P06-09 to 23 : Speed analog command direction input on DI5
P04-14 Acceleration time 200ms/1000rpm for direct (belt) drive >500ms/1000rpm for gearbox with some lash
P04-15 Deceleration time 200ms/1000rpm for direct (belt) drive >500ms/1000rpm for gearbox with some lash
P06-40 Speed analog instruction gain 1rpm/V to 500 if you want it to turn 5000rpm when Acorn pulls out +10V
(use this parameter to fine tune the spindle speed)

Bench test.

Install on the spindle

run AF_J-L and record the measured moment of inertia ratio and write it in P01-04

Now the servo will work ok.
You can go deeper in the settings to tune the drive for maximum torque gain or best speed for rigid tapping together with Acorns parameters.

These are the basic changes to do from the factory settings.

Uwe

[suntravel]

For a new project, I have set up an other JMC Servo as a spindle drive.

Since it drives the spindle 1:1 I decided to use the build in encoder. That's working perfect, just connect the ABZ/A/B/Z outputs to Acorns encoder input.

Set up 10000 lines for the 17bit Tamagawa encoder.

With only 2 Parameters in the servo drive it can be tuned to have less than 5 rpm deviation from 0-6000 rpm

Till now I have nothing to complain about the AC JMC servos, regardless if used as spindle or axis drive, easy to wire direct to Acorn, easy to tune and reliable.

Documentation could be more detailed, they also have some nice homing and axis pairing functions I have not tested out yet.

Uwe

[cnckeith]

thanks for posting, these look nice.

[Black Forest]

What connector is on the drive to connect it to the Acorn? DB44 or DB25? Or something else? I have more money invested in crimping and wiring tools that I have in the Acorn with pro license! All these Knipex tools start to add up!

[suntravel]

What connector is on the drive to connect it to the Acorn? DB44 or DB25? Or something else? I have more money invested in crimping and wiring tools that I have in the Acorn with pro license! All these Knipex tools start to add up!

not sure, but could be JAE LVDS 51 pole, male plug with solder on is supplied with the servo kits.

German JMC distributor is working on RJ45 Adapters to save users from fiddly soldering

Uwe

[bubblevisor]

THanks Uwe for posting this useful resource. I am in the process of installing the same JASD spindle motor on my Syil X5. Looking at your wiring diagram I cannot understand why you chose to wire the ALM pins to a SSR before connecting to acorn. Is this not just connecting a relay to another relay?

[suntravel]

THanks Uwe for posting this useful resource. I am in the process of installing the same JASD spindle motor on my Syil X5. Looking at your wiring diagram I cannot understand why you chose to wire the ALM pins to a SSR before connecting to acorn. Is this not just connecting a relay to another relay?

I must admit to be no electronic engineer...

For some reason I thought it is a good idea to isolate the driver from Acorns Input. It works this way reliable, but it is maybe not necessary

Uwe