Advice on buying servos.

[Ger21]

OK, so just to be clear. A 400W AC servo motor would typically be coupled to a driver powered by AC at a voltage less than 240v?

No, most of the currently available 400w AC servos are 220-240V

[Agathon]

No, most of the currently available 400w AC servos are 220-240V

Nice.

[Agathon]

What do you think of this: http://www.ebay.co.uk/itm/Samsung-RS...-/282340382590

Might it be suitable for my app or am I barking up the wrong tree?

[Agathon]

Is it important that the servo driver and motor are from the same manufacturer? Or is just that the driver and motor must match electrically speaking?

[Ger21]

The most important is that the encoder connections on motor match what the drive requires.
Some encoders/drives use 12 or more wires, some use as few as 5 or 6.
Imo, unless you really know what you're doing, it's best to but a matched set from the same manufacturer.

Not sure if they are available over there, but here inthe US, and Canada, DMM are the best bang for the buck.

[Agathon]

The most important is that the encoder connections on motor match what the drive requires.
Some encoders/drives use 12 or more wires, some use as few as 5 or 6.
Imo, unless you really know what you're doing, it's best to but a matched set from the same manufacturer.

Not sure if they are available over there, but here inthe US, and Canada, DMM are the best bang for the buck.

Many thanks Gerry. Those DMM servos are very good VFM.

[Boyan Silyavski]

The Samsung servos need a Samsung drive. Or better said, you could not hook other servo motor to a brand drive. As it auto detects motors and will give " Faulty" all of the time. Samsung motors have 9 wires to encoder, some 11. The one on link is with 9 wires.

The only way you could make a similar motor work is Universal servo drive like Granite Devices.

And yes, that motors are good price and good ones, but you can check the Samsung PDF manual link i send you earlier and see that for yourself. But remember what i told you about the servo cables. Dont make decisions without knowing what will cost you when you include them. The good thing is these motors are in Europe. You could buy the drives for around 130 each, used.

DMM are out of question in Europe. Going that way is better to buy Chinese drives or the second hand Samsung. I have pondered over that many times last years and every time money and price prevails.

[Agathon]

Just out of interest, via a socket screw axial to the ballscrew, I used a precision torque screw-driver (usually used for very carefully setting the torque on small screws) to see how much torque was required to move the table. As might be expected the initial torque required to overcome the stiction was higher that what was required to keep it moving. However the maximum torque required was surprisingly low - 0.5 Nm. I might just pop a 16mm slot-drill in a collet and see how much torque is required to make it cut steel...