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Benja
21-08-2018, 04:26 PM
My machine uses AC for everything. a single transformer with 3 outputs 40v 24 v and 12v ac

The stepper drivers that are in it are also AC. They can accept 30v - 80v AC. I want to upgrade the drivers to a digital stepper driver such as the EM806 which would also seperate the drive voltage from the logic voltage which i dont think is a bad thing either.


Could someone give me advice on whether running DC stepper drives within an AC system is Good idea or not does it make any difference? The breakout board runs on 24v ac

From what I can see after investigation the only use for the 40v is to the drivers so it wouldnt affect anything else. the 24 runs a number of other things so i would leave the original transformer in just seperate off the the new drives with a new DC power supply
I would really appreciate some advice on it.

Clive S
21-08-2018, 06:00 PM
My machine uses AC for everything. a single transformer with 3 outputs 40v 24 v and 12v ac

The stepper drivers that are in it are also AC. They can accept 30v - 80v AC. I want to upgrade the drivers to a digital stepper driver such as the EM806 which would also seperate the drive voltage from the logic voltage which i dont think is a bad thing either.


Could someone give me advice on whether running DC stepper drives within an AC system is Good idea or not does it make any difference? The breakout board runs on 24v ac

From what I can see after investigation the only use for the 40v is to the drivers so it wouldnt affect anything else. the 24 runs a number of other things so i would leave the original transformer in just seperate off the the new drives with a new DC transformer.

I would really appreciate some advice on it.

Ok Transformers are AC not DC If you are going to use EM806 drive 68v Dc would be good.

https://www.zappautomation.co.uk/electrical-products/power-supplies-43/linear-power-supplies.html

or build one.

Benja
21-08-2018, 06:19 PM
Hi Clive yes that was the power supply i had in mind . so it doesnt matter that all the other contol gear is AC no? I never even realised there was such a thing as AC stepper drives or an ac bob!

I realise it sounbds a bit crazy as of course a dc psu is powered by ac. but since everything is stright up AC I thought i would check with folk who know about these things.


That one at zapp is out of stock. I would have no idea how to build one. this might do it i guess? https://cnc-plus.de/en/CNC-Electronics/Power-Supplies/CNC-power-supply-with-4x-10A-and-max--72V-DC-voltage-output-.html If I hooked it up to the original transformer. not quite the seperation I was looking for

Clive S
21-08-2018, 06:55 PM
Hi Clive yes that was the power supply i had in mind . so it doesnt matter that all the other contol gear is AC no? I never even realised there was such a thing as AC stepper drives or an ac bob!

I realise it sounbds a bit crazy as of course a dc psu is powered by ac. but since everything is stright up AC I thought i would check with folk who know about these things.

These will work off AC https://www.ebay.co.uk/itm/2DM860H-2phase-NEMA23-NEMA34-Stepper-Motor-Driver-32bit-DSP-DC80V-1-5-6-0A/401403682399?hash=item5d75861e5f:g:02MAAOSwb85alhS 1

Benja
21-08-2018, 11:27 PM
These will work off AC https://www.ebay.co.uk/itm/2DM860H-2phase-NEMA23-NEMA34-Stepper-Motor-Driver-32bit-DSP-DC80V-1-5-6-0A/401403682399?hash=item5d75861e5f:g:02MAAOSwb85alhS 1

Thanks that looks great but I was hoping to get something sorted in the next couple of days.

I just hooked up an EM 503 to the X using another psu i have spare, just to prove concept as it were.
Fuck me its a diffent machine!
Only did one axis. They are drivers I'm intending to use on the Novamill upgrade. I had to tune down a bit but shocked at the difference.

The 806's will be brilliant i think, im almost tempted to put 3 ph hybrids on but i think thats for another day. i'll see how well this goes first for the money its looking like a very good upgrade.

Clive S
22-08-2018, 06:46 AM
I would have no idea how to build one

There are only 3 components in the unregulated power supply and have look at this excellent vid from Joe on this forum. Using a 500 or 650 Va toroidal transformer, 3 caps and a rectifier.

This would be better than a regulated PS.


https://www.youtube.com/watch?v=4OoQQg76ar4&list=PL1FIADAKba_tiLqXbUkzD30sZjtp_VyqY

Benja
22-08-2018, 08:05 AM
Hey that doesnt look too bad, I'll have to figure a shopping list for RS then.
Going to Zapp this morning to pick up the 806's :)

Clive S
22-08-2018, 08:40 AM
Hey that doesnt look too bad, I'll have to figure a shopping list for RS then.
Going to Zapp this morning to pick up the 806's :)

Here you go.:-
1 off https://www.rapidonline.com/vigortronix-vtx-146-625-125-625va-toroidal-transformer-230v-primary-2-x-25v-88-0012

1 off https://www.rapidonline.com/50a-bridge-rectifier-metal-case-519318

3 off https://www.rapidonline.com/samwha-hc2a478m35040ha-4700uf-100v-85deg-hc-snap-in-capacitor-11-3121

3 off https://www.rapidonline.com/lcr-ep0882-p-35mm-nylon-capacitor-mounting-clamp-11-3004

Benja
22-08-2018, 10:51 AM
Here you go.:-
1 off https://www.rapidonline.com/vigortronix-vtx-146-625-125-625va-toroidal-transformer-230v-primary-2-x-25v-88-0012

1 off https://www.rapidonline.com/50a-bridge-rectifier-metal-case-519318

3 off https://www.rapidonline.com/samwha-hc2a478m35040ha-4700uf-100v-85deg-hc-snap-in-capacitor-11-3121

3 off https://www.rapidonline.com/lcr-ep0882-p-35mm-nylon-capacitor-mounting-clamp-11-3004


Bloody hell man, thank you very much. :) I think ive got a bit of AL that should do the job nicely too

Benja
23-08-2018, 11:36 PM
806's now installed , using a leadshine switching psu at the min and will swap out for the linear once its built :) although the switching will work fine im sure sounds like the linear will be more efficient and possibly more stable in the long run. also fun to build! :) thanks Clive for your help.

Those drivers are night and day from the analogues I was using, motion is smoother and quiter even though ive gone from 1/10 to 1/5 Ms. Very happy but with a faint feeling I should have gone for the easy servo even though logic says this setup should be just as accurate.

Key thing for me I think is I know these are now running at full power. The proof will be in production.