Centroid Community CNC Support Forum

Hello everyone,

I'm upgrading a 2-axis CNC lathe with a Centroid Acorn (Lathe Pro) and using Maxsine EP100 AC servo drives for the X and Z axes.

My current setup is as follows:
- The STEP/DIR signals come from the Acorn's H2.
- These signals go through an optocoupler board (EL817, which converts 5 V → 24 V).
- The controller's STEP+ and DIR+ connect to the optocoupler outputs.
- For STEP− and DIR−, I'm not entirely sure whether they should go directly to the Acorn's COM (0 V) or to the 0 V side of the optocoupler outputs.

Right now, the drives power up, but the motors don't move. I suspect the problem could be with the ENA pins:
- The Maxsine EP100 has ENA+ and ENA− inputs, which I haven't connected yet.
- Do they need to be connected (e.g., ENA+ = +24 V and ENA− = 0 V) ​​to enable the drive?
- Or can the EP100 be configured via parameters to ignore the ENA input and always remain enabled?

My main questions are:
1. What is the correct way to wire STEP− and DIR− when using Acorn with an optocoupler board? Or is it not necessary?
2. Do the ENA+/ENA− pins need to be connected to 24 V/0 V for the drive to accept motion commands?
3. Has anyone successfully connected Acorn directly to the Maxsine EP100 and can share wiring examples or parameter tips?

I would greatly appreciate any help.

Thanks!

This is the manual on which I have been based

1.
Assuming you are talking about optocoupler boards with connections like this: https://www.amazon.com/Icstation-Optoco ... OI1HC?th=1.

I do not believe those optocouplers are necessary. Follow the second drawing on page 5 of your attached manual and use 24V for VCC. Wire the PULS-/SIGN- terminals to a resistor then to the STEP and DIR pins on Acorn's H2. H2 is open collector outputs as shown in the diagram. Use the Maxsine recommended current limiting resistor value (1.3k to 2k ohms). I'd choose 1/2 watt resistors for this.

If you were to wire this with the optocouplers, then I would connect the IN+ terminal to the DB25 output and IN- to Acorn power supply common. Optocoupler OUT pin to PULS-/SIGN- and optocoupler GND pin to power supply common. PULS+/SIGN+ go to 24V. Chose resistor as before.

2. By default, yes. Wire +24V to the EP100 COM+ terminal (pin 18 on CN1). The Acorn EN pins go to CN1 pin 10 (DI1) for Servo On. This quick start manual does not show any parameters for reassigning the inputs but it does mention that the 53rd and 54th parameters can be used to force an input terminal on. This may be used for forcing the drives to stay enabled.

3. Follow the instructions on the last page of the manual you attached to get the inputs set up correctly. The main change you need to make is to set PA20 so it will ignore the pulse inhibit input.

Other parameters (PA01, specifically) may need to be set based on your motor, which should be mentioned in the full manual for this drive. I only found a Chinese version of the full manual. However, it may have been set at the factory or dealer.

If you want to use them with more than 100000 Hz, use linedrivers, to convert Acorns Output in RS422.

Otherwise, I would connect them to the DB25 5V Step/Dir, that will work better than 24V Headers and Resistors

Uwe

OKEY, thank you very much for the support
I will implement it to do a test this weekend

Hello, good afternoon. I had a problem with the driver connection. When I was already getting everything ready on the Centroid card, I don't know if I made a bad connection and the PLC burned up. Fortunately, since I'm new to this, I ordered several cards. Before I burn any more, I'd like to share some connections I made quickly and see if you have any additional tips you can point out in case I'm missing something.
Thank you very much in advance for support.

Where / how does your GND (0V) connect to the drive? Actually, I think that's answered below, its PIN 10.

Also, Servo On is not normally switched with Enable (despite the name). Most drives want this pulled down to 0V.

Just checked the manual, correct. Servo On needs to be taken the 0V. The way to do this is to set an output for 'No Fault' condition, wire the middle of the corresponding output to 0V and the Normally Open side to the drive SON input. All 3 drives need this, I tend to take the 3 (or however many axis you have) to a common buss or common wire.