AKM53K max torque with SimuCUBE

I have a question regarding the Kollmorgen AMK53K winding regarding its capabilities when running with the simucube + ioni pro HC. I am planning a build and have sourced Mige and Kollmorgen motors, and am weighing up the pro’s and con’s to move forward.

From my understanding the AMK53K is current bound when paired with the IONI Pro HC.
AMK53K specs (from official spec sheet);
Peak torque: 30.1Nm
Torque constant: 1.24A
Winding resistance: 1 Ohm.

Assume 32.2V RMS available from power supply.
Assuming Max torqueV = (Vrms / R) * Torque constant
And Max torqueI = I * Torque constant

Max torque from voltage: (32.2/1) * 1.24 = 39.93Nm (motor bound)
Max torque from IONI Pro HC: 25 * 1.24 = 31Nm. (Almost perfect).

I see it reported that the AKM53K is bound to ~26Nm on the IONI Pro HC, how is this the case, the calculations above imply that this motor is almost a perfect match and can be run to it’s peak torque.

Thanks in advance for your help!

You are confusing Irms and Ipos.

IONI Pro HC 25A pos = 25/1.4142 A rms = 17.67A rms.

Torque is thus 17.67x1.24 - 21.9NM

Cheers,
Beano

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Ah of course, thank you Beano.
By this corrected math then, using the Simucube and IONI Pro HC I would get the following peak performance from kollmorgen motors;

AKM53G: 20.5Nm (voltage bound)
AKM53K: 21.9Nm (current bound)
AKM54L 19.96Nm (current bound)
AKM64L 29.3Nm (current bound)

The only question remaining is I swear I have seen yourself post about 26Nm being possible form this motor, am I mistaken in having read this?

I am currently sourcing a SinCos encoder for kollmorgen, at which point I will weight up the cost/value proposition. Currently it looks like a kollmorgen build will cost me ~3 times as much as a small Mige build. Obvious question you get all the time Beano - worth it?
Impossible to answer I’m sure!

Beano I believe had a 54K which will do 26.52Nm @25A MMC

I am pretty sure Beano will say his 65L (37.12Nm) is well worth it lol…

Finding a decent Kollmorgen on ebay is the key really (cost wise) and then either hopefully getting it with the Incremental or the EnDAT with the SinCOS output would be nice or retrofitting a SinCOS.

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Yeah I’m keeping an eye on eBay, but I have sourced new kollmorgens nearby that aren’t entirely out of the question cost wise.
If anyone can point me at a good source of kollmorgen motors or encoders please let me know - simtech is the only reseller I know of, I’m current corresponding with an industrial source for new motors.

As for encoders I have sourced brand new kollmorgens with the 10,000 ppr encode, and am trying to source sincos encoders.
The 54K is where I’m at right now, I realise now that’s where I got the 26Nm number from.

Once I get the final quotes in for a new 54K with 10k or sincos encoder I can make my mind up over what I’m gonna build - affordable mige, or - ridiciculous and indulgent kollmorgen…

I am not sure where you are located but pretty much any motion control distributor could have them… I think they do tend to be pretty constant as far as pricing though across the board… As for any of the 5x servos the K winds are better matched to the SimuCUBE.

Kollmorgen does not actually have a SinCOS as standard equipment except as a secondary 2048 on the DA - ENDAT, not sure if the DB - ENDAT does as well with the multi turn but it may… it is a secondary output though and not the primary ENDAT control… The other of course is the EJ - 10K.

For a true SinCOS you will have to figure out how to adapt one which could be anything from a Mige encoder (which is fairly inexpensive about $150.00) to the Heidenhains which are relatively expensive ($250.00 -$300.000 for a 3600line if you can find it)… You could also go BiSS which is really expensive ($700-$800)

I have AKM52G, AKM53K, and AKM54K servos with BiSS available. Feel free to PM me with any questions.

Thanks Davy, it doesn’t look like I’ve been around long enough to be able to PM anyone yet :slight_smile: (Or it’s too difficult for me to figure out how…). Can you PM me - I should be able to reply once PM’d, and I do have some questions :).
Cheers.

Another query - ideal power supply situation for an AKM54K.

By my calculations Peak voltage = 18.08Vrms, and Peak current: 17.67Arms (motor is current bound).
Therefore Peak power draw = 18.08 x 17.67 = 319.5W.
Accounting for efficiency losses a 350W PS would just about do it, and 480W would be absolutely fine.
Do I have the right of this?

Now next question;
Given a peak voltage requirement of 18.1Vrms, and a peak current requirement of 17.67Arms, we need a power supply capable of supplying this. Looking at the specs of the mean well NDR 480 it seems like the 480-24 is a better fit?
NDR 480-24: 24V @ 20A
NDR 480-48: 48V @ 10A

If I understand correctly the the 48V model would not be able to drive the AKM to more than 15Nm.
Again - do I have the right of this?

If you use the 24 power supply you will probably significantly limit torque due to resistance of the servo but you will lower the rotational speed.

To be safe I would get a SDR-480, The resistance and other electrical specs for the 54K are similar to a Large Mige and it has been known to actually clip the NDR-480 at times causing under voltage faults. It seems like the servos do end up drawing a little more current than is calculated when running in Torque control mode. (ie a small Mige will get up to 400w at times)

The 48V @ 25A MMC will drive the 54K to 26.52Nm (amperage Limited)

It looks like you Might get 19.96Nm out of the 54K when running 24V if I did my calculations correctly (voltage Limited)

Hmm, what math did you use to calculate the 24V torque limit? As I see it The 24V supply will more easily service the high current requirements without menaingfully limitting on voltage?
Peak voltage req of 54K is 18.08V?

You need to consider the winding resistance, 48V DC will be able to push higher current through a resistance than 24VDC.

Most of the servos we use have a relatively high winding resistance, and might be voltage limited, as opposed to current limited by the IONI…see my list I provided yesterday in another thread. You can compare the 53K vs 53G, the K servos are typically wired for speed (RPM) with lower Torque coefficient, compared to the G-series AKM servos, which are wired more for torque, whilst speed of the servo is significantly lower.

ps: Just a very simplistic answer of course.

Cheers,
Beano

Kollmorgen has also BiSS-C type encoders in their stock as an option for new motor, you could possibly use those too if you like. They use Hengstler AD58 series encoders which are not bad.

As Phillip (Beano) said it has to do with the winding resistance/voltage… I estimated that the Voltage would be half of the 48v with losses so voltage numbers I just divided in half (there could be some variance there) and then used the standard calculations which I believe is the same as you did with all of the 48v options above as your numbers all appear correct there… For most of the Kollmorgens they are voltage limited so lowering the voltage just makes it worse.