UC100 and "noisy environments"

This Section is for users to discuss hardware

UC100 and "noisy environments"

Postby jandyman » Mon Apr 02, 2018 9:40 pm

I am considering getting a UC100 to use with the UCCNC software. It is attractive because it is cheaper than the UC400ETH (because it includes the UCCNC SW license), should be a tad easier to configure, and is not a separate piece of HW that have to mount. I could just plug the DB 25 connector straight into my Gecko 450 and away I go.

I heard it said that USB controllers can be unreliable in "noisy environments". Offhand, I don't think I have a noisy environment. It's not like I've got a motherboard mounted in a box with stepper motor drivers inches away. My laptop is several feet away from the Gecko 450, and that's all there is to my setup other than the actual stepper motors.

Is there a reason the UC100 would be a poor choice for this setup?
jandyman
 
Posts: 7
Joined: Mon Apr 02, 2018 9:31 pm

Re: UC100 and "noisy environments"

Postby Robertspark » Mon Apr 02, 2018 11:52 pm

I know of at least 2 people running uc100's with CNC plasma cutters... And it does not get much more noisier than that. Only negative being limited pin count (depends on your requirements though)

There is a limiting length on usb cables.

What do you intend to use it for (mill plasma router lathe laser 3d printer, what)?
Rob
Einstein ― “If you can't explain it to a six year old, you don't understand it yourself”
...working my way through the 1000+ ways things don't work to find the one that does
UC400eth, UC300eth, UCCNC v1.2106, Neuron Lite
UCCNC v1.2105 Macro Manual
Robertspark
 
Posts: 820
Joined: Sat Sep 03, 2016 4:27 pm
Location: Nr Liverpool, England

Re: UC100 and "noisy environments"

Postby jandyman » Tue Apr 03, 2018 12:51 am

I have a 24x48 CNC router. It has two x motors driving belts in parallel but "mirrored". Other than that it is a really standard setup, not even a variable speed spindle. It works just fine now with Mach3 and an Ethernet SmoothStepper with just a ribbon cable going to the DB25 connector on the Gecko 450, but I want to get off of Mach3.

I suppose I might think of a real spindle someday, but I'm not there right now, and it might never be necessary. I'll just be cutting wood, occasionally plastic, and maybe experiment with aluminium (VERY cautiously).
jandyman
 
Posts: 7
Joined: Mon Apr 02, 2018 9:31 pm

Re: UC100 and "noisy environments"

Postby ger21 » Tue Apr 03, 2018 12:53 am

The price difference between a UC100 and a UC400ETH should only be about $35, including the UCCNC license for both. The UC400ETH will give you an option for more I/O if you need it in the future, and it has some other features that the UC100 doesn't support, due to it's limited number of pins.
Gerry
UCCNC 2017 Screenset - http://www.thecncwoodworker.com/2017.html
ger21
 
Posts: 1039
Joined: Sat Sep 03, 2016 2:17 am

Re: UC100 and "noisy environments"

Postby jandyman » Tue Apr 03, 2018 12:59 am

I didn't see that the UC400ETH included a license, and it looked like the UCCNC SW license was about $70. Plus the price difference between UC100 looks like about $37. So isn't that a price difference of over $100? What part did I get wrong?
jandyman
 
Posts: 7
Joined: Mon Apr 02, 2018 9:31 pm

Re: UC100 and "noisy environments"

Postby ger21 » Tue Apr 03, 2018 1:30 am

jandyman wrote:I didn't see that the UC400ETH included a license, and it looked like the UCCNC SW license was about $70. Plus the price difference between UC100 looks like about $37. So isn't that a price difference of over $100? What part did I get wrong?


Where are you getting your prices from? A UCCNC license is usually $55-$60
A UC100 is about $110
A UC400ETH is about $148
Gerry
UCCNC 2017 Screenset - http://www.thecncwoodworker.com/2017.html
ger21
 
Posts: 1039
Joined: Sat Sep 03, 2016 2:17 am

Re: UC100 and "noisy environments"

Postby jandyman » Tue Apr 03, 2018 2:23 am

The prices I saw are all in Euros, so I converted. I got the prices from their website. But the major point is that when I looked at the UC100 on Amazon a few days ago, it included a UCCNC software license, and UC400ETH did not. I just went back and looked again and that seems no longer true as far as I can tell. I swear I'm not imagining things!
jandyman
 
Posts: 7
Joined: Mon Apr 02, 2018 9:31 pm

Re: UC100 and "noisy environments"

Postby cncdrive » Tue Apr 03, 2018 9:25 am

Noisy environment is in other words industrial environment where there are other equipments too, not only the CNC machine which equipments can generate noise and transmit it though the mains.
Noise can be also caused by the machine itself, e.g. a spindle motor, a plasma unit etc. In general, devices which switching high voltage and or high current causing voltage spikes and possible noise.

USB is more sensitive to noise, because USB is ground referenced communication which means that both the PC and the USB device are referenced to the same 0Volts ground potential.
The USB endpoint device and the PC ground are connected with a wire in the USB cable.
The issue with this is that if the PC ground gets noise, the ground potential is fluctating with high frequency and/or with high amplitude can cause communication problems, because the wire which makes the ground connection has inductance and resistance and so the 2 ground points will not move instantly together.

Ethernet is isolated communication. There is no common ground points on the PC side and the endpoint device. The data is transfered through high frequency mini transformers called ethernet magnetics which are built into the RJ45 jack of the UCxxxETH controllers and also one transformer is on the PC's LAN card.
Because the 2 endpoints are isolated the above mentioned ground point fluctaction caused by electrical noise can't cause problems to ethernet communication.

Ofcourse noise can be usually filtered and with proper grounding scheme it can be kept under control when it causing no issue, but especially plasma units are often heavy noise generators and especially cheap chinese ones often have no sufficient mains filter which makes things worse and so we recommend to use ethernet controllers for plasma applications.
cncdrive
Site Admin
 
Posts: 2110
Joined: Tue Aug 12, 2014 11:17 pm

Re: UC100 and "noisy environments"

Postby jandyman » Tue Apr 03, 2018 2:31 pm

Thanks for the informative reply. That's kinda what I figured and based on that I think I'm fine with USB.

Even though the UC400ETH isn't that much more expensive, I'm thinking I really don't need it. The only thing I could conceivably add to my system - which already works fine on just the DB25 interface - is a real spindle instead of a router.

But it looks like my Gecko 450 makes the VFD pins available for that, still only using the DB25 and routing the VFD pins through to a separate output connector. So that would probably also work.
jandyman
 
Posts: 7
Joined: Mon Apr 02, 2018 9:31 pm


Return to Hardware

Who is online

Users browsing this forum: Google [Bot] and 3 guests

cron