MDI Spindle Voltage Incorrect

[morchips]

Hello all,

I have a hitachi WJ200 VFD attached to my acorn

In essence, I have:

* Hitachi WJ200 VFD
* Motor, at 60hz is 1750RPM
* Acorn controller
* Shielded connection to VFD

VFD is setup:

* 120Hz max (via A004 and A012)

Centroid is programmed for:

* Min Speed: 80
* Max Speed: 3500

This is the problem, from centroid I get:

* Set to 1750 (50% of max speed), outputs 6.6v (on a multimeter) or 80Hz, expected output would be 5v generating 60Hz
* Set to 3500RPM (100% of max speed) outputs 10V (on a mulimeter), or 120Hz, the correct expected output

Is there some kind of curve with the spindle output that would be causing this?

[Gary Campbell]

If you wish your analog voltage to be linear, set the wizard rpm minimum to zero. Then set your desired minimum speed in the VFD parameters (Htz Min)

[morchips]

Thanks for the reply – I set the minimum to 0 in centroid, and I get the same result.

[Nigelo]

Disconnect wires from both Vout and COM analog terminals on Acorn and measure voltage on those terminals when manually commanding 1750 rpm. Does this produce 5vdc

Did you clean up wiring as we suggested in your other thread?

And PLEASE, post a new and current Report.zip

[Gary Campbell]

Have you tried adding a 0.1mfd capacitor across the Acorn analog terminals?

[cnckeith]

Hello all,

I have a hitachi WJ200 VFD attached to my acorn

In essence, I have:

* Hitachi WJ200 VFD
* Motor, at 60hz is 1750RPM
* Acorn controller
* Shielded connection to VFD

VFD is setup:

* 120Hz max (via A004 and A012)

Centroid is programmed for:

* Min Speed: 80
* Max Speed: 3500

This is the problem, from centroid I get:

* Set to 1750 (50% of max speed), outputs 6.6v (on a multimeter) or 80Hz, expected output would be 5v generating 60Hz
* Set to 3500RPM (100% of max speed) outputs 10V (on a mulimeter), or 120Hz, the correct expected output

Is there some kind of curve with the spindle output that would be causing this?

disconnect the VFD from Acorn and go thru the Spindle Bench test starting on page 30
https://www.centroidcnc.com/centroid_di ... manual.pdf