Has anyone here got experience of tuning any of the AC Servos from China. I am considering getting some, specifically the Lichuan A4 type as per the pic below.
The manual doesn't seem to have much info on tuning so I downloaded their software and eventually managed to get it loaded on an old XP computer (couldn't get to work on W10 even in compatibility) The software however looks to be just an easy means of setting parameters and there doesn't seem to be much in the way of tuning compatibility built in, in other words it is just a computerised method of enter parameters rather than using the drives buttons.
I am a bit wary of buying the drives/motors in case they are a nightmare to tune so it would be good to hear from anyone who has done so and their experience of it.
Hi,
there are a plethora of cheap Chinese servos and the prices are very attractive......but the documentation is Chinglish at best and worse......
most of them do not have setup and tuning software, you have to program them by pushing buttons like a microwave. Setting up and tuning servos
is entirely hard enough without having to accommodate baffling documentation and no PC based tuning software.
I have bought three 750W B2 series Delta servos for my new build mill. Delta has very good tuning software, easily the match of any US, European or Japanese
manufacturer. They certainly cost more than the bargain basement Chinese stuff but still way less than US/European/Japanese stuff.
I was trying to help a guy on-line to set up an tune ToAuto servos, I had no problem with the quality and performance of the servos but trying to decipher the
documentation and sorting all the button-pressing programming errors was just a drag....and I had the advantage of having set-up and tuned other servos,
specifically Delta and Allen Bradley.....so the basic tuning concepts I well understand. If you are new to servos I would not recommend the cheapest Chinese
servos, they are likely to sour your experience. Delta and DMM on the other hand have good software, good support and sparkling performance at fair prices.
Craig, I have tuned many a servo, mainly Allen Bradleys from the early Electrocraft BRU style through DSM's to the DSD's, also a few others including the Berger Lahr/Schneider/Telemcanique used on the Chiron in my Avatar.
Most of them had decent software to assist in the manual tuning.
Anyway I digress, you mention the B2 drives, is it these?
There seem to be many Chinese sellers with slightly different looking drives but likely all pretty similar. The software for the above drives seems to be all Chinese so not much use but maybe it is available in English from somewhere else.
I could probably muddle my way through the tuning but it will be a bit more difficult seeing as they may end up on my Plasma Y axis so two motors/drives on that axis and that makes tuning a bit more difficult.
Anyway thanks for your reply it is appreciated.
Hi,
I'm guessing you are Hood of Mach renown, and think therefore that you'd have no problems setting up and tuning these cheap servos, after all you have
plenty of experience.
The Delta servos to which I was referring are these:
The B2 series are Deltas effective entry level model with a a 160,000 cpr encoder. The later and slightly more expensive A2 series has a 1,280,000 cpr encoder but more importantly is dual loop.
Thus you can close the position loop on a linear scale say....without requiring a feedback capable motion controller. The second loop is closed at the drive. Really clever.
There are even later models, the A3 and B3 series that have 24 bit absolute and multiturn absolute encoders.
I think any of these models will compare very favorably, and possibly exceed earlier Allen Bradley servos.
You will note that the 750W B2 series in the link is priced at $438USD, which is no doubt more than the Chinese servos at which you are considering but still much cheaper
than Allen Bradley or Yaskawa say, and yet they perform very satisfactorily in comparison.
Thanks for the info regards the Deltas, they sound like they may be worth looking at, might also enquire about the drives SZGH sell, they are a bit more expensive than the Lichuan but if they have decent software then it may be worth it, then again the Deltas may be the best route. At the moment I am just using Allen Bradley DSD's but one blew the other week so I had to rob one from the Beaver NC5 mill so I was thinking maybe some new motors/drives may be the way to go for the plasma, we will see.
Just looked and these, I think, are the ones you are talking about, not too bad a price at all. Slightly more expensive than the Lichaun but only fractionally.
Hi,
yes they look to be genuine B2 series Delta servos.
I bought a 400W model (same as your link) to experiment with prior to buying the three 750W models for my new build. I was very VERY impressed with the 400W model.
It was to have found a home on my existing mini-mill but I ended up selling it to my boss, and we made a speedo calibrator out of it.
My previous AC servo experience had been with Allen Bradley and I found the Delta's to be every bit as good in terms of quality, flexibility, control modes
etc. and at a fraction of the cost.
Suffice it to say that I found the 400W Delta to be everything I'd hoped for and therefore proceeded to buy the three 750W models. The 750W version is only about $40USD
more than the 400W version, ergo I got the larger one.
I did not realise at the time that the A2 series which has an even greater resolution encoder, but more importantly dual loop was only about another $50USD over the B2 series.
Had I known about the dual loop feature I might have paid the extra........not that I really have use for the feature......just its what I want as opposed to what I need!
I bought from Fast-To-Buy on the basis of range of products including Yaskawa, Delta, Mitsubishi, Panasonic etc. They have good, maybe not the absolute cheapest, but good prices.
They charged me $80USD each for three day DHL shipping to New Zealand from China. I tracked them from China to my doorstep in 2 days and 14 hours......so I got what I paid for.
Note that Fast-To-Buy have their own servos called ToAuto and they promote them like hell. I have no reason to doubt quality or performance but the documentation is Chinglish
and no PC based tuning software. The price may be attractive but I'm more than happy to have paid a little extra for Deltas.
Thanks again for the info. The dual loop would be wasted on the plasma but may be good for the lathe although that would require much bigger motors/drives (3Kw or so) but hopefully that won't be needed any time soon
Hi,
quite agree, I don't really need dual loop either. I bought preloaded C5 ground ballscrews, and paid a pretty penny for them, so dual loop is not required because
the quality of the screws is such that rotational position is within a few um......and more I don't require.
If I had known about the A2 features all that would have happened is I spend another $150USD and not really gain anything. I have done that sort of
nonsense before!!!
Chinese servo drive tuning question
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