X-Controller tripping out GFCI outlet

I just finished assembling and wiring up the new X-Carve and associated X-Controller. Unfortunately, it is knocking out the GFCI outlet randomly. Initially, it occurred while I was testing out the setup of the machine. I reset the outlet and continued on with the testing. Since it appeared to be more stable I decided to try an air cut of the sample project with the router turned off. It got about 50% through and the GFCI outlet tripped again. I tried it a second time and it got all the way through. I then decided just to leave the controller on without a computer attached to the USB port and the router off. After about 30 minutes, the GFCI outlet tripped again without anything happening (no movements). One thing to note is that this outlet has never tripped in the past and I’ve run just about every shop tool you can imagine on it. There also hasn’t been any moisture over the past few days and only this outlet has been used. I also double checked the other outlets on the GFCI circuit and everything looks ok. I opened up the X-Controller and double checked the wiring according to the instructions and verified that each noted electrical connection was secure. I also double checked the wiring on the machine. After doing this, I tried another test of the sample project with the router off and the GFCI outlet tripped again about 30% of the way through. I can replace the outlet, but I’m skeptical that this is the issue since it hasn’t happened with any other piece of electrical equipment I’ve used. During the tests after the initial failure, I verified that there was nothing else plugged in on the outlets that make up the GFCI circuit.

Any thoughts? Could the power supply be defective? After finally finishing a workbench and assembling the machine I can’t wait to carve something.

The chassis ground is for safety and is not “suppose” to carry current. Realistically, the PS leaks a very small amount of current in order to filter the AC line. This is well below the trip setting for a GFI. If your leaking enough current to trip the GFI AND you have verified the electrical feed is correct, it is probably a faulty power supply. Since it doesn’t trip immediately, it sounds like a leaky cap in the filter.

There are GFI testers for around $10 you can pickup and verify the receptacle. It will also confirm it’s wired correctly.

1 Like

That is a reasonable test.

The power consumption of an X-Carve is really low compared to other shop tools so it would surprise me if it was the X-Carve to blame. It is more likely that a VAC or grinder creates spikes that trigger the limit switches of the X-Carve than the other way around.

Thanks for the helpful comments. The active community is one of the reasons I chose to buy an X-Carve. My plan is to go to the hardware store after work and purchase both a GFI tester and a new GFCI outlet. If the tester shows that the outlet is fine, I’d like to see if it fails with the X-Controller plugged in, but without the X-Carve or any other connections plugged. If this is the case, it will be easy to move the X-Controller to try it with other GFCI outlet circuits in the house. Since GFCI outlets are required by code in a garage and that is where I’m planning on running it I’ll need to get something that works there somehow. Hopefully these tests will isolate whether this is an electrical infrastructure issue or a hardware issue with the X-Controller.

I feel the same as RobertCanning. But, I’d be sure to purchase the best quality GFCI I could find. Installing a new one would also set you up with ‘clean’ copper wire under the attachment screws.

A GFI doesn’t look at safety ground itself to sense a fault. The hot and neutral wires are ran through a transformer in opposite directions. All of the current carried by the hot is returned through the neutral and the difference is zero. When ground leakage occurs, a voltage is induced across the transformer as the hot and neutral are no longer equal.

You could drive an external current through the GFI ground as long as the neutral and hot are balanced. Externally generated charges carried into the GFI ground should have no affect on tripping.

Leaky caps happen. IF there was a real problem where the ground carried all of the current, it would trip immediately. A leaky Y Cap in the filter would manifest itself in a similar way. Without having it to actually test. This is pure speculation.

A GFI tester showed that the outlet was fine. I contacted Inventables support and they shipped out a replacement power supply. I swapped this in tonight and I’ve run for several hours without any issues. This is well beyond what was possible before. I’m cautiously optimistic that the problem is solved. Many thanks for the feedback and helpful hints.

1 Like

Great to hear. Keep the thread updated if the problem comes back. I would think in most circumstances the machine wouldn’t be used on a GFI and any issue like this would have been masked.

Inventables has a datasheet for the 240W PS.

https://www.inventables.com/technologies/enclosed-power-supply

It’s under the right side of the page under Files and Attachments. The worst case leakage rating is stated less than 1mA and should be well under the GFI trip rating.

1 Like