[j3dprints]

I have read only reviews on Chinese servos 'looking well built' and I want to know if they have a good performance record with anyone.
I want to know this because for my machine with 400w / 750w drives they are the same price as Leadshine hybrids. I think others face this choice.
So I am looking at choosing between proven name brand and Chinese servos.

I read a thread before on the same topic but it devolved into a political / global economic thread.

Example servo, $350
https://www.aliexpress.com/store/pro...760394727.html

Example Leadshine easy servo $300
https://tinyurl.com/yc5mfbbr

Also as sizes go up servos can be cheaper.
As to if 'Leadshine is actually leadshine' you can verify this through them if seller is an authorised distributer.

Thanks for answers I ask a lot of questions but I think I am close to finally ordering my parts!

[RCaffin]

Steppers
Pro
Very simple electronics
Con
Very limited power
Quite limited torque at high speed
If they lose a step, that's it, and you may not be told about it unless your controller is quite expensive)

Servos
Pro
Much bigger range of power available (as much as you want)
Much higher speeds available with torque
If they fault (position error too big) they tell you
Con
Slightly more complex electronics and mechanics (ie encoder)
Higher cost typically
Controller needs tuning

As for brands - generally, You Get What You Pay For.
I use Gecko+servo, and cannot comment on other combos.

Cheers
Roger

[ger21]

I've heard that those chinese servo's work well, if you know how to set them up. I've heard that documentation is severely lacking.
I opted for DMM servos, as the price is only slightly higher, and they have better documentation and support. They would probably be much more expensive in Australia.

Comparing an AC Servo to the Leadshine "Easy Servos" is comparing apples and oranges. The AC servos are much more powerful. The Easy Servos are still stepper motors, with a torque curve that drops off as rpm's increase. AC servos have a flat torque curve, up to 3000 RPM

[WesM]

The dmm tech 400w servo and a dyn2 drive come in at around $285, thats around the same price as the chinese servo systems. I would tend to trust a brand that provides warranty and documentation on their products as opposed to a FOB china product with little or no support. If you fry one of those chinese drives you are on your own, I have read of DMM being able to repair or providing at cost replacements.

I was just looking at those chinese drives/servos for a retrofit im planning and I honestly see no cost benefit for them as opposed to DMM Tech products. The shipping from china typically makes them about the same price, at which point I lean heavily twords DMM.

[ger21]

The dmm tech 400w servo and a dyn2 drive come in at around $285,

You need a DC power supply for those, so expect to pay about $60-$75 per motor for that. The 200V motors with Dyn4 are about $100 more, but don't require the power supply.
And don't forget cables, which can add another $50-$100 per motor.
DMM sells a complete kit of 3 400w/Dyn2 for about $1450, which is a lot more than $285 per axis.

I agree about the chinese pricing though. The shipping brings them right up to DMM's pricing. What the DMM's have going for them, is that they are about $150-$250 cheaper than anything else not made in China.

[j3dprints]

You need a DC power supply for those, so expect to pay about $60-$75 per motor for that. The 200V motors with Dyn4 are about $100 more, but don't require the power supply.
And don't forget cables, which can add another $50-$100 per motor.
DMM sells a complete kit of 3 400w/Dyn2 for about $1450, which is a lot more than $285 per axis.

I agree about the chinese pricing though. The shipping brings them right up to DMM's pricing. What the DMM's have going for them, is that they are about $150-$250 cheaper than anything else not made in China.

Thanks for the info! Yes, you are correct, multiply the price by 1.33 (Aud to USD currently) then add more for shipping for DMM (for us Aussies). So prices are less for Chinese.

The Chinese servos come with cables too which to me is an advantage. Do they also require a power supply or not? I am yet to investigate the wiring setup required. I think I could work out setting them up with help from electronic engineer friends and some (lots) of reading.

[RCaffin]

If you fry one of those chinese drives you are on your own,
Contrast this with the guarantee from Gecko on their latest drives: you fry it, we fix it, for free.
In fact their Viper Drive, the 203V, survived an open challenge a year or two ago.
Good support (from any company) is $$$ in hand.

Cheers
Roger
(I am quoting Gecko because I use them; I have no connection to them.)

[mactec54]

Thanks for the info! Yes, you are correct, multiply the price by 1.33 (Aud to USD currently) then add more for shipping for DMM (for us Aussies). So prices are less for Chinese.

The Chinese servos come with cables too which to me is an advantage. Do they also require a power supply or not? I am yet to investigate the wiring setup required. I think I could work out setting them up with help from electronic engineer friends and some (lots) of reading.

Don't go by the price, go by what you are getting, compare the packages, you won't find any in this price range, that will equal the Dmm system, just there encoder advantage, makes them superior to any one else

[j3dprints]

Don't go by the price, go by what you are getting, compare the packages, you won't find any in this price range, that will equal the Dmm system, just there encoder advantage, makes them superior to any one else

The 3 axis DMM kit you guys (US or near) get for $1441 I pay around $2200 AUS for after shipping. There would be additional import costs, unless you broke up the shipping. I think DMM could also work with AUS people on this, they seem like good people.
The chinese servos however I can obtain for around $1100 AUS (that's 3 axis) which I believe offer just as many features as DMM and can be run on high voltage AC. I think they might even have additional features.

[mactec54]

The 3 axis DMM kit you guys (US or near) get for $1441 I pay around $2200 AUS for after shipping. There would be additional import costs, unless you broke up the shipping. I think DMM could also work with AUS people on this, they seem like good people.
The chinese servos however I can obtain for around $1100 AUS (that's 3 axis) which I believe offer just as many features as DMM and can be run on high voltage AC. I think they might even have additional features.

The cheaper Chinese servo's don't even come close as far as features go, it's what you can afford to buy, and what you will be happy with, if a stepper was a thought, then any servo system would work for you and you would be happy with it

[ericks]

I have read only reviews on Chinese servos 'looking well built' and I want to know if they have a good performance record with anyone.
I want to know this because for my machine with 400w / 750w drives they are the same price as Leadshine hybrids. I think others face this choice.
So I am looking at choosing between proven name brand and Chinese servos.

I read a thread before on the same topic but it devolved into a political / global economic thread.

Example servo, $350
https://www.aliexpress.com/store/pro...760394727.html

Example Leadshine easy servo $300
https://tinyurl.com/yc5mfbbr

Also as sizes go up servos can be cheaper.
As to if 'Leadshine is actually leadshine' you can verify this through them if seller is an authorised distributer.

Thanks for answers I ask a lot of questions but I think I am close to finally ordering my parts!

I have Leadshine stepper drives, been using them for a few years.... Never ever had any issues with them. So i expect their servo stuff to be good too.

[WesM]

I think Mactec is referring to the DMM tech encoders 16bit (65,536 ppr) vs the 2500 ppr chinese product.

However if it really is almost twice as expensive, I guess you have to evaluate what tech support, documentation and a industrial encoder are worth.

[RCaffin]

IF the boxes meet Australian supply regulations - IF, then all you should need is a simple mains filter between the wall and the boxes.
One filter for the whole system would be enough.

Cheers
Roger

[j3dprints]

IF the boxes meet Australian supply regulations - IF, then all you should need is a simple mains filter between the wall and the boxes.
One filter for the whole system would be enough.

Cheers
Roger

Thanks, and if they need something to dampen our power spikes? I believe depending on the area you're in here you can vary up to 250v or something (I'll have to check). If that's the case, and they only appreciate up to 245... ? Is it an expensive device required?

[WesM]

Thanks, and if they need something to dampen our power spikes? I believe depending on the area you're in here you can vary up to 250v or something (I'll have to check). If that's the case, and they only appreciate up to 245... ? Is it an expensive device required?

It may be worth talking to DMM and seeing what they recommend. They have been very helpful the last couple times I called about their Servo/drives.

[mactec54]

It may be worth talking to DMM and seeing what they recommend. They have been very helpful the last couple times I called about their Servo/drives.

If you did go with the Dmm system and use there high voltage Servo Drives, you would have to use a line reactor, or a Transformer so you can stabilize your line voltage, or you would kill the servo Drives with the over voltage that you are experiencing, this would be a must to get under control for any system you use

[j3dprints]

They do indeed seem good. You can get them for 600 shipped.

Is 2500 ppr really a big deal on these servos?

Also servos outperform a leadshine in every respect, really? I am not after super fast rapids, I would like Tormach potential which boast under 150ipm for their ipm speeds on their mills and good ACCURACY. I am aware they use open loop with torque reserve and good engineering to not miss steps. With leadshine closed loop steppers I could achieve no missed steps and similar IPM / accuracy I think. Or with their clones. I have read steppers if they don't miss steps can actually be more accurate than servos (in my price range).

Prices for Aussie customers and pros/cons I've noted are as follows:
Leadshine CLONE CLOSED LOOP steppers for like $700 AUD delivered (clones so.... not as great drivers?)

Leadshine closed loop genuine (chinese models) are more like $900 (steppers, not servos, but is this really a disadvantage if you're not chasing massive IPM)

Chinese Servos come in at 1000 to 1200 (good but 2500ppr, and bad manuals),

Chinese servos with better encoders - around 1500-1600

DMM for just under $2000 delivered to Aus.

I am really really looking toward option 1 - leadshine clones. Save 1400 over DMM. I reckon they will equal whatever Tormach has and the money I'll save will be better spent on other things - better ballscrews later, hiwin rails for x and y, A nice surface table, or even money off a Skyfire / Tormach / VMC which I might upgrade too later.

[Al_The_Man]

Is 2500 ppr really a big deal on these servos?
.

Keep in mind that that is the basic quadrature count, most controllers will times this by 4 by counting all four edges.
Resulting in 10k pulses/rev in this case.
Al.

[mactec54]

They do indeed seem good. You can get them for 600 shipped.

Is 2500 ppr really a big deal on these servos?

Also servos outperform a leadshine in every respect, really? I am not after super fast rapids, I would like Tormach potential which boast under 150ipm for their ipm speeds on their mills and good ACCURACY. I am aware they use open loop with torque reserve and good engineering to not miss steps. With leadshine closed loop steppers I could achieve no missed steps and similar IPM / accuracy I think. Or with their clones. I have read steppers if they don't miss steps can actually be more accurate than servos (in my price range).

Prices for Aussie customers and pros/cons I've noted are as follows:
Leadshine CLONE CLOSED LOOP steppers for like $700 AUD delivered (clones so.... not as great drivers?)

Leadshine closed loop genuine (chinese models) are more like $900 (steppers, not servos, but is this really a disadvantage if you're not chasing massive IPM)

Chinese Servos come in at 1000 to 1200 (good but 2500ppr, and bad manuals),

Chinese servos with better encoders - around 1500-1600

DMM for just under $2000 delivered to Aus.

I am really really looking toward option 1 - leadshine clones. Save 1400 over DMM. I reckon they will equal whatever Tormach has and the money I'll save will be better spent on other things - better ballscrews later, hiwin rails for x and y, A nice surface table, or even money off a Skyfire / Tormach / VMC which I might upgrade too later.

You heard wrong they could never be as accurate as AC Servos, even the cheap ones, when you have to chase your dollars as I said before buy what you can afford, but don't get the servos that Edmunns just listed, if these where the ones you looked at

It looks like the genuine Leadshine is your best bet , with there encoders at,2500=10,000ppr if they are incremental, yes Encoders are a big deal, these servo's are not worth the extra money to buy them, the Dmm Encoder is 65,384ppr standard

[RCaffin]

Yeah, you REALLY need to check that.
The problem is that a lot of such gear is primarily aimed at the USA market, and so caters to 110/220 VAC. Pushing up to 240 VAC is usually OK, but here in Oz we do get higher surges at times. A lot of that 110/220 VAC gear can't handle that.

I once had an entire jellied-lead battery backup system (many $k) go up in flames for exactly that reason. The batteries melted down after the switching transistors shorted out. Eventually we took to not switching the power on until after 9 am and switching it off before 5 pm - to avoid the mains surges which were happening when local industry powered up and down. The surges AND spikes were incredible, and Elcom were not helpful.

Cheers
Roger
Sydney