Application lost the connection with uc100

Try contacting the developer at: http://cncdrive.com/contact.html

you have noise in your system that is freezing the UC100 chip.

The UC100 is not at fault - this is most likely a noise issue

Check your USB connections.

Are you using an old tower PC or laptop?

Try a filtered USB cable or wrap the USB cable in some ferrite rings.

are there any large electrical items coming on/off during use of your machine in the same AC connection line?

Have you gounded the machine frame?

The noise is either coming form the machine side - the SC control card could be at fualt. Or its coming from the PC side.

are there any large electrical items coming on/off during use of your machine in the same AC connection line?

This was the issue i had turning a compressor off and on that was on the same AC as the stepcraft. Apart from putting stuff onto another wall socket is their anyway around this Rory?

Hi,

had the same problem always if starting a cooling pump. Then I used a "suppressor capacitor / anti-noise capacitor / decoupling capacitor".. I don't know the correct english translation and this helps 100% !
You have to connect the wires in parallel to the wall socket.

You will find them on ebay for example (here a german result): suppressor-capacitor

or have a look here on the German Wiki page just to give you an idea how to search for: capacitor
Look for those with 3 wires.

you can get a ferrite ring and wrap the USB cable around this a few times - this does a good job of suppressing some noise.

like this

And you can ground the Machine. Filtering the AC line into the machine power supply also helps. We use a filter in our control boxes also.

Its all about noise and EMC. if the Machine is correctly grounded and the AC line filtered its not a problem.

Often its not a problem even without these measures. But this is what can be done.

And a capacitor / filter is also a good option as per Doc Browns recommendation. Just be very careful as only a qualified trained person should be doing anything to AC connections.