VFD wiring help! Omron 3G3M1 vs Delta MS300

[boristouchstone]

Hi all!

I'm looking forward to building a Sorotec Compact Line CNC router with the Centroid Acorn board and Clearpath servos.
However, wiring is a bit of an issue for me as I have little precious experience in that department.
What's particularly troubling is figuring out which VFD to choose and how to wiring it to the Acorn board
I'm in Europe and the Omron 3G3M1 and the Delta MS300 are the most available quality VDFs with sensorless vector control so I would to use one of these to pair up with the Teknomotor 2.2kw Electrospindle.

I've searched the web and this forum but couldn't find any wiring information with regards to these VFDs.
Does anyone have any experience and would like to offer a hand?

I've Included screenshots and the entire manual for both.

Omron 3G3M1

Delta MS300

Kind regards,
Touchstone

[centroid467]

Those are both pretty standard VFDs and either should work for running a 400Hz router spindle. They both have configurable inputs and outputs so you'd need to read the manual to figure out how to assign the functions. This being a router, you probably do not need to worry about wiring for reverse.


We have some generic schematics that will cover the required control wiring for either of these. Either of the two schematics will work for you unless you have specific requirements on the wiring.
S15009 shows an overview of how the VFD, axis drives, and E-stop contactor could be wired. The VFD enable goes through the E-stop contactor's auxiliary contact to disable the VFD when the E-stop is tripped.

S15008 shows a generic VFD and the Acorn itself. It is a little bit simpler since it does not pass the control signals through the E-stop contactor.


Wiring the power signals should follow the manufacturer's recommendations given in their manual. They'll state what kind of circuit breakers and filters are required for safety, reliability, and best performance. Use a cable designed for carrying VFD signals to carry the drive output to the motor. Pay attention to cable shielding and termination as well.



I'd say it is better to use the default assignments for the VFD I/O when possible. For instance, on the Omron drive, DI6 is likely to be the default Run Forwards input and you may as well just keep that assignment.

You'll note from the schematics that you should assign an input on the VFD to act as a fault reset signal. You should also assign a relay output on the VFD to give the fault status.

[boristouchstone]

Thanks for the reply.

I had another look through the schematics with ChatGTP's help and this is what it has come up with regarding the Delta VFD:

{{{{{{{{{{{{{{{{{{{{{{{{{{{{{{{{{{{{{{{{{{{{{{{{{{{

1. POWER CONNECTION
VFD INPUT (Mains Power):
* L1, L2 terminals on VFD ➝ Line (Live) and Neutral from your 230 V single-phase supply
* PE ➝ Earth ground
VFD OUTPUT (To Spindle):
* U, V, W ➝ spindle motor wires (order does not matter unless motor direction is incorrect — then swap any two)
* PE ➝ spindle ground
Even though the VFD takes single-phase input, it outputs 3-phase power to the spindle — this is expected.

2. CENTROID ACORN ➝ VFD CONTROL SIGNALS
Spindle ON/OFF (Digital Run Command)
* Acorn OUT1 (digital output) ➝ VFD terminal MI1
* Acorn GND (digital ground) ➝ VFD terminal DCM
VFD Parameter:
* 09-00 = 01 → assigns MI1 = "RUN Forward"
* 00-02 = 01 → Run command from external terminals

Spindle Speed (Analog Control)
* Acorn PWM-to-Analog Board (or low-pass filter output)
➝ VFD terminal AVI (analog voltage in)
* PWM-to-Analog GND ➝ VFD terminal ACM (analog common)
VFD Parameter:
* 00-05 = 01 → frequency reference is AVI (0–10 V)
* 10-00 = 06 → set analog input AVI = 0–10 V = 0 to max frequency
* 01-00 = 400 (or match spindle’s base frequency, e.g., 400–600 Hz)

3. OPTIONAL FAULT FEEDBACK TO ACORN
You can wire a fault output from the VFD to an Acorn input:
* VFD terminal RY1C → Acorn digital input (e.g., IN1)
* VFD terminal RY1A (NO) → Acorn GND
Set 11-00 to assign the relay function:
* 11-00 = 01 → "Fault output" (RY1A closes when fault occurs)

SUMMARY
Spindle Enable (M3): Acorn OUT1 - MI1
Digital GND: Acorn GND - DCM
Spindle Speed (PWM): PWM → Analog - AVI
Analog GND: PWM GND - ACM
Optional Fault In: RY1A → IN1 - Acorn Input

}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}

Simple enough.. I guess.

My question is: What the hell is Digital GND? I see AN GND, but I'm assuming that goes to ACM.

Also, I'm not quite understanding how to wiring the fault feedback

Could I get some help?

[centroid467]

Digital GND (DCM on the VFD headers) goes to the return/common of the Acorn's power supply or separate PLC power supply. It is also labeled COM on Acorn H9. (If you have multiple power supplies i.e. one to power the Acorn and another to power the PLC inputs/outputs, then their common terminals need to be tied together as well.)


Wiring the fault feedback is pretty simple too. Looking at the Delta basic wiring diagram you'll notice terminals called RA, RB, and RC. On our schematic S15008, it shows Fault Com and Fault NC.

From Delta's diagram, you'll note that RB is a normally closed contact and RC is the common terminal of that relay. As per S15008, you would wire RC to the power supply common (like you did with the DCM terminal). RA would then get wired to an input terminal on the Acorn - you can use any of them on H1 or H4.