Losing steps/position, again

[Doddy]

Just to be pedantic: You've shown a number of power suppliers - not transformers (there's a subtlety in the wording there). I'd hold onto the 3A PSU for services and sensors, and supplement it with a new toroidal transformer for the drivers. Possibly hold onto the 12V depending on what it's currently used for, but it would make sense to rationalise the cabinet as far as is practicable, if for nothing else other than ease of maintenance). Your friend's suggestion of using two toroidal in parallel - broadly speaking, yes, but you're getting little benefit than using a single big one, unless you already have access to these? (or are looking to increase in future?, possibly just provision for the space of a future toroidal? - might make sense). I'm not quite sold on wiring two transformers in parallel that might have a different manufacturing tolerance - you could end up pumping some power from one transformer into another, but the power involved might be lost in the noise.

Your choice of 36V for the Z? - the original idea was to understand if the increased voltage improved your most susceptible axis. But that's your call and your game - leave you to it. I'd recommend replacing with the BFG toroidal transformer in the future.

Steppers with 6 wires?, measure the resistance between these - three will be (likely) connected to each coil - centre tapped, you probably should connect between the two wires of each three that has the greatest resistance (example you might find A-B = 1.5R, B-C = 1.5R, A-C = 3R, connect to A-C)

[ngwagwa]

Just to be pedantic: You've shown a number of power suppliers - not transformers (there's a subtlety in the wording there). I'd hold onto the 3A PSU for services and sensors, and supplement it with a new toroidal transformer for the drivers. Possibly hold onto the 12V depending on what it's currently used for, but it would make sense to rationalise the cabinet as far as is practicable, if for nothing else other than ease of maintenance). Your friend's suggestion of using two toroidal in parallel - broadly speaking, yes, but you're getting little benefit than using a single big one, unless you already have access to these? (or are looking to increase in future?, possibly just provision for the space of a future toroidal? - might make sense). I'm not quite sold on wiring two transformers in parallel that might have a different manufacturing tolerance - you could end up pumping some power from one transformer into another, but the power involved might be lost in the noise.

Your choice of 36V for the Z? - the original idea was to understand if the increased voltage improved your most susceptible axis. But that's your call and your game - leave you to it. I'd recommend replacing with the BFG toroidal transformer in the future.

Steppers with 6 wires?, measure the resistance between these - three will be (likely) connected to each coil - centre tapped, you probably should connect between the two wires of each three that has the greatest resistance (example you might find A-B = 1.5R, B-C = 1.5R, A-C = 3R, connect to A-C)

Sorry for the incorrect terminology. I won't be throwing anything away and the 12V was for the V5 Spindle controller which isn't used.
Z was a typo should have been X

I have discovered the coils are centre tapped and I know which are which, my problem now is finding out where the tap leads go to.

[JAZZCNC]

I have discovered the coils are centre tapped and I know which are which, my problem now is finding out where the tap leads go to.

They don't go anywhere just terminate them so can't short.

[ngwagwa]

They don't go anywhere just terminate them so can't short.

On the machine side I can't get to them inside the cabinet (short of cutting them where they enter the stepper). According to the Denford documentation they do not connect to the umbilical. I will look if I can see them on the underside of the machine tomorrow.
Just before I left the workshop I was reading somewhere that was saying depending what you do with the tap wires will give more speed or more torque but I can't seem to find it now, my . laptop must be as forgetful as me.

[dazp1976]

Your choice of 36V for the Z? - the original idea was to understand if the increased voltage improved your most susceptible axis. But that's your call and your game - leave you to it. I'd recommend replacing with the BFG toroidal transformer in the future.
)

My thoughts too.
Look at the inductance level on the steppers. Square root the figure and then multiply by 32.
This will give you your ideal voltage for the steppers to sing.

For example an inductance of 3.5mh= 3.5 Sqrt *32 = 59V!!
Inductance of 2.5mh= 2.5 sqrt*32 = 50V!!
Inductance of 8mh= 8 sqrt*32 = 90.5V!!
See where I'm going with this?

You'll find 36V with nema23 size motors is a bit of a dissapointment. You want at least 48V.

[ngwagwa]

M

You'll find 36V with nema23 size motors is a bit of a dissapointment. You want at least 48V.

Daz you seem to have missed a few of the posts. The 36V was/is only intended as a test/stop gap measure

[JAZZCNC]

Inductance of 8mh= 8 sqrt*32 = 90.5V!!
See where I'm going with this?

Ye, I see it as well and now go find me a typical low Nm nema17 or 23 with an inductance of 8Mh.! . . . . Doesn't matter how you want to try to spin it, you can't put 100v on a small stepper and expect it to last long. Put 240V on it and watch what happens to it. (In fact I think I have some small motors kicking around and a mains 240V drive, so when I get back to work I'll show you exactly what happens!)

If you don't believe me then go read the rest of the Gecko info where you got those figures from and read what Maris Fremanis the Owner of Gecko as to say about it and the effects of having too high a voltage.!

I know you probably didn't like me pulling you up on what you said, but it was wrong and misleading so it could quite easily end up in someone burning their house down if they listened to your wrong advice. That's why it needed pointing out and why you need to watch what you say unless known to be absolutely correct.

[dazp1976]

Ye, I see it as well and now go find me a typical low Nm nema17 or 23 with an inductance of 8Mh.! . . . . .

3nm with 6.8mh https://www.ebay.co.uk/itm/3pcs-Nema...kAAOSw5CZcig1u
3nm with 9mh https://www.ebay.co.uk/itm/1pc-Nema-...1338d93d000784
3nm from supposed respected company: 6.8mh in parallel 27.2mh in series!! wth. https://www.automationtechnologiesin...l23h286-20-8b/
0.54nm Nema17 with 4.8mh is shocking enough afaic. https://www.automationtechnologiesin...epper-motor-3/

[JAZZCNC]

3nm with 6.8mh https://www.ebay.co.uk/itm/3pcs-Nema...kAAOSw5CZcig1u
3nm with 9mh https://www.ebay.co.uk/itm/1pc-Nema-...1338d93d000784
3nm from supposed respected company: 6.8mh in series 27.2mh in parallel!! wth. https://www.automationtechnologiesin...l23h286-20-8b/
0.54nm Nema17 with 4.8mh is shocking enough afaic. https://www.automationtechnologiesin...epper-motor-3/

See here you go again giving out wrong information and not understanding how steppers work.!!

First, it's 27mh in series not parallel and that isn't uncommon when wired in series. For our needs with routers, it's 6Mh which just means it's a shit motor and to give it a wide birth.

It's a known fact that motors wired in series have higher Mh and require higher voltage if you want speed from them, this is why most of those you list have high inductance. If you look all except the third on list only have 4 wires and are probably Series wound motors.? Again anyone who fits these to a router is a moron who didn't do his research.!

However, all of this doesn't change the fact that your advice that "Doesn't matter wether you have Nema 17/ 23/ 34size motors etc, the drivers regulate output voltage to the motors themselves." is seriously wrong and potentially dangerous if took to the extremes ie: 240Vac drives with nema 17 motors.

I'm done with this now.!!

[dazp1976]

See here you go again giving out wrong information and not understanding how steppers work.!!

First, it's 27mh in series not parallel and that isn't uncommon when wired in series. For our needs with routers, it's 6Mh which just means it's a shit motor and to give it a wide birth.

It's a known fact that motors wired in series have higher Mh and require higher voltage if you want speed from them, this is why most of those you list have high inductance. If you look all except the third on list only have 4 wires and are probably Series wound motors.? Again anyone who fits these to a router is a moron who didn't do his research.!

However, all of this doesn't change the fact that your advice that "Doesn't matter wether you have Nema 17/ 23/ 34size motors etc, the drivers regulate output voltage to the motors themselves." is seriously wrong and potentially dangerous if took to the extremes ie: 240Vac drives with nema 17 motors.

I'm done with this now.!!

You asked for examples. I wouldn't use them for paperweights and they theoretically should not be allowed on the market to dupe people.
Would avoid Automation Technologies when it comes to a lot of steppers too. Pretty dire afaic. Seen many recommend A,T. Shocker.