Centroid Community CNC Support Forum

Hey Folks,

I am about to finish Acorn 4.5 on Hyundai/Mazak HiT 8G gang tool lathe conversion with DMM DYN4 1.0kW motors. Everything is wired and works as it should except for the Delta C2000 I am still to wire. Have a few questions here:

1. The reason I bought C2000 is in hope one day to get C axis (mostly as a simple degree defined indexer). In the 4.5 I see C axis in the wizard. Does it mean it can be working without expensive unlock? Is it possible to program the parts with C axis in Intercon (just like with rotary axis on a mill)?

2. I don't have the positioning card, yet, so for now I'd like to wire it just 'to make it work and start making parts'. Looking at the manual:

https://www.deltaacdrives.com/wp-conten ... Manual.pdf

and the TB316:

https://www.centroidcnc.com/dealersuppo ... ds/316.pdf

the questions are:

a) on page 5 of TB316 it says FWD run is NO, and REV run is NC. The schematics on p. 4-1 in the manual does not show that way and I don't see anything in the setup parameters defining that. Do I miss something?

b) Same page on TB316--RC1 and RB1 (I assume the line "normally Input 10, should read as Input 5--correct?) shows it as NC. When I was talking to DMM guys about Fault out on DYN4 they mentioned all the DMM faults can be connected to input 5 in parallel with VFD. My understanding DMM is NO, so here we obviously have a conflict. Should I just use RA1, instead (corresponded to parameter 2-13 Output Relay1 set at 11--Fault)? Also, the RC1 repeats next line after RB1. Should it be RC2 (and paralleled to RC1, since both of them are Yellow)?

c) from previous conversions, for Analog control of speed I usually used ACM and AVI. Now it also mentions AFM1 (the wiring on C2000 manual p. 4-1 shows it as 0~10V). Looking at the parameters setup table on p. 5 of the TB316 it shows the 3-20 should be setup at 7 (power output 10v=100%). Looking at the C2000 manual p. 11-11 shows that parameter 3-20 is at all Output Frequency (default 0, with no other options). The closest with '7 Power output 10v=100%' is parameter 3-23, but this one is for AFM2. It is totally confusing, and also, no idea where to connect it on the Acorn board and what does it do.

d) MO1 and MO2 are for full speed and zero speed and I see inputs can be configured in the Wizard. But then I don't see their COM. The C2000 manual p. 4-1 shows something looking like their common--MCM, which defined as 'Photocoupler Output', but no mention in the TB316. What to do with those?

Would appreciate any insights on those.

Best, M

Any insights on any of the questions?

Mark,
First, I have no experience with that particular VFD. I also have LIMITED experience with C axis positioning, though I have experimented with it.
Looking at the manual you provided (thank you for that) its pretty straight forward to wire up as a standard VFD.

A VFD is a not a servo drive nor is it meant to replace one. Most VFD's allow an encoder input to position the spindle for something like a spindle orient for a tool changer. With encoder input, they can try to maintain speed.

To have a true C axis, you'd need a way to engage and disengage a servo motor to the spindle for positioning. OR a very large servo motor meant to be used in that manner. IN one mode, the spindle drive would take 0-10VDC analog signals and drive the motor as a TYPICAL VFD would. It would need forward and reverse inputs as Acorn is currently not capable of supplying a -10-0+10VDC ananlog signal. Only 0-10VDC

IN positioning mode, the drive would be signaled to switch to position mode and would have to accept step and direction signals from Acorn.
DMM Technologies has special firmware for this, but I had limited success with it, others say they have been able to get it to work. I have yet to see a video showing it successfully working.

Wire and Program your VFD so you can get your lathe running. Worry about C axis implementation at a later date.

Perhaps others with more C axis experience can chime into the conversation.

Marty

Some of your questions (e.g. whether fault is wired to INP10; whether direction is controlled via a form C relay; and where to connect the AFM analog monitor) are because you are using an Acorn board, and TB316 was written with closed-loop controls (Oak, Allin1DC etc.) in mind.

If you use one output for forward and one for reverse, then you would be using normally-open contacts in both cases. If you use one output for run, then chain that to a second output for direction, then you would use the normally-closed contact of the direction relay for FWD, and the normally-open contact of the direction relay for REV.

You would connect the fault relay NC terminal (e.g. RB1) to whatever Acorn input you have selected to be the spindle inverter okay input.

Analog speed control goes to AVI and ACM.

AFM1 (and AFM2) are analog outputs from the drive, back to the controller. If you are using a controller with analog input capability, then you can use one of these signals to put a spindle load meter on the screen. Since Acorn has no analog input, these signals are not applicable.

If you want to use MO1 and/or MO2, then you would connect them to Acorn inputs, and you would connect your 24V return (0VDC) level to MCM.

Marty is correct in his post. Use the last page of the TB and setup the VFD without encoder feedback to get it running without a C axis option. This TB is for OAK and ALLINONE so you will not us AFM1 the Acorn is a DYI not industrial and at the price point does not have the features of the higher end controls, obviously. We install C Axis on a lathe using a Large 11kw servo (only with the oak). This is connected on the back shaft of the spindle with a tooth clutch and a 3-1 timing belt due do the high inertia of the spindle, gears, chuck and work combined in order to have the accuracy and repeatability required. We also have multiple mcodes we write in order to have it engage, disengage correctly with a proximity sensor, pneumatic valve and home sensor.

Also, with the VFD you would only be able to repeat within 20-30 encoder counts single line TTL so the variation on a radius would be extremely large.

The C2000 may be able to be use but you would need a special Delta input board and then write mcodes to command a limit amount of positions which would be pretty much worthless for all the effort you put into it. I would never go down that path. The only way is a servo motor.

Thank you all for clear and detailed answers!

Re: C axis. We have one part, which we always make for our products (about 50 pcs a month). It involves clocking at 45% two holes--one offset from the center in Z plane (0.063 " diameter .820" deep) and another side hole in X plane (.100" diameter, .125" deep). After that there is a threading operation over the side hole. As it is it takes 4 operations--1. Lathe skim cut, shaping OD and parting. 2. Mill--offset hole in Z plane. 3. Mill--side hole on a fixture to clock against the Z plane hole. 4. Back to lathe for threading and final polishing.

I almost think even mounted on a spindle simple indexing plate with two 45% clocking holes and with some means of pinning it and hand operation for that part will be by far easier and let the make the part in only one operation. Obviously, the holes are small enough and there is no any significant force involved.

Any ideas/suggestions/voice of wisdom on this one?

Best, M