Centroid Community CNC Support Forum

Chuck is playing it safe.
I think the dropping resistors would work..your mileage may vary.

You can buy this Meanwell Power supply that has both +24VDC adn +5VDC if you wanted (cheap too!):
http://www.jameco.com/webapp/wcs/stores ... -1?CID=PDF

Still need large 24VDC supply for your steppers

I think you're right Marty and really don't understand why they suggest a separate 5V power supply instead of using the 24V logic power supply and dropping resistors. I'm sure there is a reason and hopefully we'll find out later when either Chuck of Keith have time to dive deep into the discussion regarding this.

I already have a 10A 24V power supply for the steppers and I have a DIN rail 5 VDC supply in my "parts" bin that I'll use for the driver / acorn interface.

Orin

For clarification, my diagram shows VAC on the unit.

This is the terminal nomenclature on the case of the CWD860H that was used. The device will accept either AC or DC inputs. (The ranges for each are different). It made more sense to use the terminal ID in the drawing.

I am using 80VDC power supplies in my setup. I took the original Drive Rack and rewired it to work with the Acorn. The Drive Rack also has a separate 5VDC power supply so I went ahead and wired the four stepper drivers for that.

Hope this clarifies the diagram.

Hello all! This thread is a little scary....scary in a good way! It's so nice to see a user 's question responded to quickly & clearly by really smart & experienced fellows. It just so happens that my Acorn (should be here Tuesday) will be used with DM542 drivers and now I have a nice clear diagram right in front of me. Color me impressed!:D

DICKEYBIRD wrote: ↑Fri Aug 11, 2017 9:17 pm Hello all! This thread is a little scary....scary in a good way! It's so nice to see a user 's question responded to quickly & clearly by really smart & experienced fellows. It just so happens that my Acorn (should be here Tuesday) will be used with DM542 drivers and now I have a nice clear diagram right in front of me. Color me impressed!:D

If we work collectively together we can help make Acorn a great product for the stepper user to consider, and maybe help drive it's future development. The more that use it, the more that come here and share their experiences, the more people will get comfortable with it, knowing they have one place to come to for some guidance, and with Centroid support staff monitoring.

I enjoyed installing their DC Servo based All in One DC on my large knee mill. Its nice to have the same software from benchtop machines to full size machines. They have a team of very sharp individuals.

Like all new software, it will take a little getting used to. Be sure to check out their knee mill tutorials. I just made a new post with a couple of links, they are a little old but they still apply. Spend the time to watch it now in advance on getting your Acorn.

Marty

762x51 wrote: ↑Fri Aug 11, 2017 4:33 pm

Well, guess now I need 3 power supplies:
PS1 - 24 VCD for Acorn Logic << fyi..this logic power supply is supplied with the Acorn CNC Controller kit!>>>
PS2 - 24 VDC for stepper motors
PS3 - 5 VDC for Stepper driver / Acorn interface

Thanks to Chuck for making the drawing so quickly and to you for posting the drawing this afternoon.

Also received a email that the Acorn is inbound -

Orin

Orin, hello. fyi.. The Acorn logic power supply (PS1 on your list) is supplied with the Acorn CNC Controller kit.
so you will need two power supplies
1.) since the stepper drives you are using require 5VDC for logic power, you will need a 5 VDC power supply for that.
and 2.) you'll need a stepper motor power supply that matches (volts and amps) the motors and drives you are using as well.

below is a photo of the acorn cnc controller kit. the included items are: acorn cnc control board, 24 vdc logic power supply, 15' shielded Ethernet cable, logic power cable, 110 vac power cord.

Good Morning Keith,

The reason I had drawn the drawing showing using the 24V logic supply and 2K dropping resistors is that method of interfacing a controller with a Leadshine type stepper driver appears to be the "standard" used by almost all of the stepper driver suppliers. I spent a number of hours this weekend trying to figure out why the Acorn is restricted to 5V and couldn't find any reason for this. Anyway, I'll use a 5V supply for the step/dir/en interface but I do think using 24V and 2K resistors should work - However, I don't want to do something that will void the warranty.

Orin

PS:

Here is a copy of a drawing out of the Acorn spec PDF file (page 3):

hello. you certainly can use the dropping resistors to knock the 24 vdc down to 5vdc to power the drive logic . that is perfectly acceptable.
however meanwell 5 vdc logic power supplies are inexpensive. and its nice to not have anything else connected to the 24 VDC logic power going to the Acorn board as a newbie precaution less chance of something going wrong. so that is why chuck has things drawn the way he does. its a safe way to do things and reliable.
alternatively you can buy a meanwell RQ-50D that has both 5vdc output and 24 vdc outputs on the same power supply.
at the time of this post the meanwell RQ-50D is $16.95
http://www.jameco.com/z/RQ-50D-Mean-Wel ... 8EALw_wcB

Good Evening Keith,

Good to see your post regarding using the dropping resistors which clarifies a lot of this discussion.

I'll be using a Meanwell MDR-20-5 (5V, 3A) supply that I have sitting on the shelf and I really do like using DIN rail mounts because it's so easy to
re-position items if need-be. Like you said, "its a safe way to do things and reliable".

I'm even thinking of 3D printing a DIN rail mount for the Acorn for the final placement after temporary hookup testing. If I do make one, after testing the mount I'll post a STEP file of it in case someone else want's to make one to mount their Acorn.

Orin

762x51 wrote: ↑Mon Aug 14, 2017 11:57 am Good Morning Keith,

The reason I had drawn the drawing showing using the 24V logic supply and 2K dropping resistors is that method of interfacing a controller with a Leadshine type stepper driver appears to be the "standard" used by almost all of the stepper driver suppliers. I spent a number of hours this weekend trying to figure out why the Acorn is restricted to 5V and couldn't find any reason for this. Anyway, I'll use a 5V supply for the step/dir/en interface but I do think using 24V and 2K resistors should work - However, I don't want to do something that will void the warranty.

Orin

PS:

Here is a copy of a drawing out of the Acorn spec PDF file (page 3):

Hi Orin,
The voltage issue is not with Acorn. Acorn can handle the 24VDC, its with the drive itself. its input can't handle anything above +5VDC, so that's why the voltage dropping resistors depending on the power supply input.

Good luck with the project. Let us know how you make out. Be sure to take a few pictures.

Marty