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Chaz
12-02-2018, 10:49 AM
Does anyone have experience of the DMM Servo systems?

http://www.dmm-tech.com/

Some interesting bits here.

1. Accept step / direction input which allows them to be driven from something other than a CS Labs IP-A or similar.
2. Centroid / Acron now offer 'official' support for these drivers.
3. Good software, their vids on youtube are good, these dont come across as your typical chinglish manuals / software.
4. Pricing seems very reasonable.

Ive ordered Centroid Acorn for my lathe, I might consider a full upgrade to servos to further improve the machine.

Thoughts / comments?

Thanks

m_c
12-02-2018, 11:29 AM
I've priced a set from them in the past, and from what I could make out, they're chinese made with a proper English manual.

Having checked the quote I got, the reason I never bought them, was at the time they were using pretty rubbish spec. I got a quote for 750W, and they had a max speed of 1080RPM.
Plus by the time all the required extra cables were added on, along with carriage, they weren't so cheap.

Most servo drives now will let you run step/dir. It's just that you're then reliant on the drives tolerances for position.
All the Kinco drives I've got can be set to run step/dir, it's just I've always used +/-10V.

Quick edit. I should add that they're current offerings are not as limited as they were. They're DYN2 drives when paired with 750W motor is still a bit limited (2000RPM), but everything else seems to be on par with other manufacturers.

Ger21
12-02-2018, 03:18 PM
Their DYN2 drives are 60V DC, while their DYN4 drives are 200V AC.

I'm using their DYN4 with 400w servos on the router I'm building.
I orderd one and set it up on my test rig, and promptly blew the drive when I powered it.
I sent it to DMM and they repaired it for free, saying it blew from over voltage.
My voltage was about 245V, which falls within their specs. They sent me a tech bulletin stating to use a line reactor to smooth out the voltage. Before I test it again, I'll be getting a transformer to lower the voltage a bit.

The reason I went with the DMM is because they have good support, and are about $100/set cheaper than the cheap chinese models on Ebay and AliExpress.

Chaz
12-02-2018, 03:23 PM
Their DYN2 drives are 60V DC, while their DYN4 drives are 200V AC.

I'm using their DYN4 with 400w servos on the router I'm building.
I orderd one and set it up on my test rig, and promptly blew the drive when I powered it.
I sent it to DMM and they repaired it for free, saying it blew from over voltage.
My voltage was about 245V, which falls within their specs. They sent me a tech bulletin stating to use a line reactor to smooth out the voltage. Before I test it again, I'll be getting a transformer to lower the voltage a bit.

The reason I went with the DMM is because they have good support, and are about $100/set cheaper than the cheap chinese models on Ebay and AliExpress.

Thanks. Most that are testing / using them are very happy. The software looks clean and functional too, certainly a strong contender for 'decent' servo stuff at hobby level. I bought Panasonic before for Thor however it was expensive and that was at 2nd hand / discount rates. I'd not have considered the Panasonic stuff at list prices.

JAZZCNC
12-02-2018, 11:54 PM
The reason I went with the DMM is because they have good support, and are about $100/set cheaper than the cheap chinese models on Ebay and AliExpress.

Think you got that wrong way round Gerry.? DYN4 Drive & 750W Motor on DMM online shop shows $457 and not sure if that includes Servo cables.
Where Lichuan 750W motor and Drive with 3Mtr cable set is $312

Ger21
13-02-2018, 12:53 AM
Shipping always pushed the chinese price up higher.
But I just looked, and see the Lichuan 400w for $350, including 10m cables. That is a good price.
I need to buy 2 more, so I may look at those.

m_c
13-02-2018, 11:16 AM
The quote I got from DMM came to about $2200, but that was in 2012.
That was for three 750W servos with DYN3 drives, all the required cables, and carriage to the UK.

What I will say though, is if you're upgrading a stepper system, the fact DMM do NEMA23/34 size motors, would make me consider those sizes to avoid having to rework brackets.