Messages

3911

General Mach Discussion / Re: CS Labs CSMIO/P-A

« on: August 04, 2018, 06:26:18 PM »

Hi Mick,
I thought to follow up on the discussion about LARGE single to three phase converters. Basically your power company would be
within theirs rights to say 'No, we will not permit you connect such a device to our network'.

The first pic is a representative circuit of an off-line input rectifier you might expect in a single phase VFD or servo drive.

The second pic show the currents and voltage when powered by a 230Vrms 50Hz supply. Note the output voltage (green trace), approx. 320Vpeak
but notice it sag between cycles. You would have to say that the DC Link capacitance is marginal for the output current.
Note the output current (red trace) is reasonably steady at about 12A but look at the supply input current (blue trace). It has peaks of about 180A!

This is a real problem....offline rectifiers draw current in high amplitude pulses with big gaps in between. The power companies hate that, they call it power factor
but in truth its more about current distortion. Any other customer hooked to the network is going to have their input supply degraded because of your device.
There are various means, both passive filters and active powerfactor correction circuitry that will solve this problem but they are expensive.

Given the plethora of electronic devices that have such simple input rectifiers and in ever increasing numbers, power companies are now having to insist on
powerfactor correction and prosecute you if you fail to comply. They have to try to protect their network for all our sakes.

Given the size of the inverter you would require for a 5kW motor I think you would come up in the power companies radar and they would ask some very pointed
questions and probably insist that you improve your installation. Industrial users are familiar with this problem and are required to spend somewhere between a quarter
and a half of their total cost of installation on the required powerfactor correction equipment.

Hood has pointed out that a 2098-DSD-030 can mange about 3kW, which is pretty damn fair. Given the exemplary torque characteristics of servos verses ansynchronous
motors I think you'd find this a very suitable replacement. Certainly it represents a practical limit to singe phase technology. DSD-030's are not nearly as common or as
cheap as the smaller 020's, but can be had for around $400US on EBay.

Craig

3912

General Mach Discussion / Re: CS Labs CSMIO/P-A

« on: August 04, 2018, 05:54:49 PM »

Hi Hood,

I use the DSD-030 drive with  H and F 4075  motors, I am sure they are around the 3Kw size

I'm sure you are right....the unit I was supplied is a DSD-020 and it does a pretty fair job of powering a 1.8kW servo. The truth is you
have to really push things to get it anywhere near its maximum and the amount of electrical energy circulating when you do is scary!

Craig

3913

General Mach Discussion / Re: CS Labs CSMIO/P-A

« on: August 04, 2018, 05:17:42 PM »

Hi Hood,

you have to register with Rockwell to get it but registration is free and painless

I tried that but without supplying a purchase number they wouldn't accept my registration.


To Mick,
sorry forgot to attach the pic that relates to my previous post.

Craig

3914

General Mach Discussion / Re: CS Labs CSMIO/P-A

« on: August 04, 2018, 05:11:26 PM »

Hi Mick,
your musing about a 5kW single phase to three phase converter:

I have attached I pic of the specs for a Allen Bradley 2098-DSD-030 which is the largest single phase servo drive that I know of.

Note the continuous output current is 15A. Note that this is the peak amplitude, ie 15A peak or 10.A rms.
Note the continuous input current is 28A and the inrush and overload current is 50A.

This drive will handle about 2.2 kW or there about.

If you want to drive a 5.5kW servo then then input current would be something like 70A and the inrush/overload current 125A.
That's just plain physics......your domestic supply would never handle that.
Servos are very 'power dense' so the situation would be even worse for an asynchronous motor, by about 25%.

The last item I highlighted in the pic is the DC Link capacitors.  The incoming AC supply is rectified and smoothed by the DC Link capacitors.
They supply the drive in between the charge cycles of the incoming rectified supply. If they are not large enough the DC Link voltage will
sag between the 50Hz peaks. If you wanted to improve the performance of a single to three phase converter this capacitance would have to
increase markedly.
A three phase drive receives rectified supply charge cycles three times more regularly and can have therefore a third the capacitance as its single
phase brother and achieve the same result.
The upshot is that you COULD run a 5.5kW motor from a single phase supply IF you are prepared to have the power supply company uprate your
connection AND you were prepared to build what amounts to a HUGE 320VDC power supply. All possible but not really practical.

Craig

3915

General Mach Discussion / Re: CS Labs CSMIO/P-A

« on: August 04, 2018, 04:38:16 PM »

Hi Mick,
Schneider have a design and production division in Christchurch, my home city as it were. I met a few of their engineers recently at an industry training
event. All nice guys and as clever as hell. They are very adept at designing and installing automated systems for food production locally and around the
world. When I spoke to them about servos they told me that even they had to pay quite steeply to satisfy their projects. I came to the conclusion, which
they generally agreed, that Schneider control the inflow of technology into New Zealand in a manner to keep the price and therefore margin high.

New Zealand has by and large no import duties or sales taxes excepting GST, rather like your VAT, and consequently we can buy stuff pretty reasonably
from any international manufacturer. That's not the case with Schneider. They are not alone.....Omron (representing Yaskawa) and NHP (representing
Rockwell Automation/Allen Bradley) have the same ethos.

They can get away with this because the lack of competition allows them to.

Craig

3916

General Mach Discussion / Re: CS Labs CSMIO/P-A

« on: August 04, 2018, 04:21:04 PM »

Hi Hood,

Why did you buy the software? it is available as a free download or at least it was.

I certainly looked and looked and then looked again....to no avail. This was at the time that you were on sabbatical.

The software is free if you buy new but given that I bought second hand.......I don't like spending hard earned money more than anybody
else but this purchase allowed me to make the best of another purchase, namely the second hand servo and drive, so I purchased and don't
feel too bad about it!

You can rest assured when I'm in the market for more servos Allen Bradley will figure very highly that I might reuse the software.

Craig

3917

Mach4 General Discussion / Re: Toolpath not showing on custom profile

« on: August 04, 2018, 01:27:14 AM »

Hi Oscar,
I don't have a CSMIO/IP and unfamiliar with its plugin. There are a few Mach4 users of the CSMIO but understand that the plugin is still in its
infancy and the personell at CSLabs have rather 'gone off the boil' when it comes to support, a shame because they used to have a great reputation
for support.

None-the-less I don't think the issue you have described has anything to do with, or at least not directly, your CSMIO plugin. My understanding is that
the tool path drawing is a feature of Machs core, not any motion plugin.

What version Mach4 are you using? I'm going to assume its the latest build....

With the default router profile open Configure/Control (note this used to be called Mach in earlier builds)/Toolpath. Pay very close attention to the settings made there.
Now open your profile (with the CSMIO) and compare the settings.

I have for instance manipulated those settings on occasion. I found for instance when viewing the toolpath for a printed circuit board etch path that the rapid
moves, typically red in colour confused the look of the tool path. I elected to make them the same colour as the background...a bit crude and not perfect
but it improved the look of the toolpath that I could determine those critical details which had hitherto been obscured.

I'm wondering if somehow the colours have been changed.....can't hurt to look. There was a thread on the forum recently that discussed the line weight that the
toolplath was drawn with. As I recall NFS has made changes that allow some of those settings to be manipulated. I'll try to fid it....it may give you some ideas
you can pursue.

Craig

3918

General Mach Discussion / Re: Need Help With New Setup (Mach3, ESS, AccuCut XPS)

« on: August 03, 2018, 07:33:17 PM »

Hi,
what breakout board are you using?

My advice would be to set up one circuit at a time and test that its working before moving on to the next. So many people set every thing
up 'according to the book', parts of it wrongly and end up with so many conflicting faults they end up hopelessly confused.

The first circuit you need to set up is the Estop. The ESS follows the same pin numbering regime as a parallel port. Thus pins 2-9
are going to be outputs, probably used for your motors. Pins 10,11,12,13 and 15 are input pins.

May I suggest that you use pin 10 as your Estop input. Unless you have some weird BoB pin 10 of the ESS will correspond to pin 10 of your BoB.
In the first instance don't bother hooking anything to the pin. Just set up pin10 port 1 in Mach as your Estop and likewise pin 10 port 1
in your ESS.

The pin when unconnected (or driven) will naturally be high, if fitted with a pull-up resistor, or low if fitted with a pull-down resistor.
You can now work out which it is. With Mach's Estop pin configured as active low, then if the pin is pulled low it will prove impossible
to reset Mach because of the enduring low condition on pin 10 of your BoB. To reset Mach you have to pull the pin high by connecting
a voltage source to it, usually via your Estop switch. With the switch contacts closed a logic high is feed to the Estop pin and Mach can be reset.
If the contacts open (or a broken wire or other fault condition) the pin will go low which Mach will detect as a fault and Estop.

Try it and see what happens. If that works out then we will hook up one of the motors.

craig

3919

General Mach Discussion / Re: CS Labs CSMIO/P-A

« on: August 03, 2018, 07:12:42 PM »

Hi Mick,

Thanks for the links but makes no sense to me to buy used motors when I can get branded stuff at such a great price

COST.  If I were to buy new, admitting that the drive has now been superseded, I would have had to shell out over $4000NZD for my MPL-A430H
and 2098-DSD-020 drive.

I agree that because you can buy Schnieder at such a good price then new makes sense, if you were paying list price or even with a good trade discount
on the list price (which is basically what I was offered by one of our electrical suppliers) they are still beyond my means.

My experience is that the only wearing parts of a an AC servo is the bearings. My servo came from a carpet factory, I don't know how much work its done,
but it hasn't 'worn' per se. If anything I would be more suspect of a secondhand drive, they are fairly high strung units. As you know electronics devices
don't wear in the same manner as mechanical devices, having said that it will 'let go' at some time. Allen Bradley is a superb brand and I do not expect their
device to have any design weaknesses.  Fortunately these particular drives are very plentiful on EBay and very reasonably priced if being selective even should
it 'go South' on me.

As it turns out that this secondhand unit, by the time I bought/made the cables and bought the setup software worked out about the same price as a new
Delta of the same power. Hence my recommendation to pay attention to the availability of cables and the price. Likewise I ended up buying from
our local Rockwell Automation distributor the setup software, cost $200NZD or about $120US. While I might have got a new Delta for the same money
I am very happy with the Allen Bradley, I've knocked up about 500hrs on it so far. Additionally the learning experience I got from perusing manufacturers
data, searching for secondhand units, making my own spindle complete with angular contact bearings and RegoFix toolholder has been worth any premium.

Craig

3920

Mach4 General Discussion / Re: work zero in mach 4

« on: August 03, 2018, 06:13:21 PM »

Hi Ken,
open Mach4 and use the view tab and select wx4.set.

This is a better screen set, it has all the features and will do everything and more of your current screen set.
If you like it just close Mach and your profile will be updated to use it instead. Easy.

Craig