Static Electricity Causes Printer Reset
I have an MK3S+, and it has been working well in the enclosure. With the weather changing, I am wearing sweaters, and when I went to go check on the printer today, I had some static electricity discharge from my arm into the case. The printer immediately beeped and reset.
What is the preferred method to ground the enclosure/printer to keep this from happening?
It sounds like the printer might have been grounded but you not...
Is there somewhere you could mount a grounding point (metal contact, resistor to ground, for fun include a neon) you could touch before touching the printer?
I touch a stainless steel kitchen sink before certain electronics but without a resistor I sometimes get a shock.
Cheerio,
RE: Static Electricity Causes Printer Reset
To eliminate static charges, I have grounded a vise and always touch it briefly with both hands before going to the printer.
Other interventions (printer ground, antistatic mat ...) have not worked reliably.
wbr,
Karl
Statt zu klagen, dass wir nicht alles haben, was wir wollen, sollten wir lieber dankbar sein, dass wir nicht alles bekommen, was wir verdienen.
RE: Static Electricity Causes Printer Reset
Would putting a touch point on the enclosure with a large resistor do the trick? I would touch the end of the resistor first, let my charge equalize, then do what I need to do.
RE: Static Electricity Causes Printer Reset
Have a look at:
and:
https://www.eevblog.com/forum/3d-printing/esd-and-3d-printers-from-filament/
Creality had an upgrade due to this too.
Hope that will help.
Cheers.
REPAIR, RENEW, REUSE, RECYCLE, REBUILD, REDUCE, RECOVER, REPURPOSE, RESTORE
Would putting a touch point on the enclosure with a large resistor do the trick?
You're still dumping charge through the system. If you are certain the enclosure itself is directly grounded and not grounding via the printer's power cable, then you should be OK.
Cheerio,
RE: Static Electricity Causes Printer Reset
Hmm. I don't understand this claim. The enclosure should be connected to the building ground for safety. I don't use the black power supply, but looking at the instructions I think that's how Prusa set it up. The frame of the black power supply is connected to the ground in the wall plug via the power cable and the power supply frame is connected to the enclosure. With the various surface finishes, there's a chance that's not true in practice in all cases (but it should be). It's uncertain if all parts of the printer frame are connected to earth ground because of all the finishes.
There is some question about the 24V however. The output of the power supply is isolated from the case and all the printer electronics is generally happy floating from building ground -- that's how Prusa set it up and it obviously works. I think it's better to earth ground the board (otherwise what is the point of the bypass caps), but there's been plenty of debate on that.
@tjh
You are essentially correct but there is no way to predict where the static discharging touch will occur, especially if printing with the enclosure open - so the route to ground may still affect sensitive electronics.
Cheerio,
RE: Static Electricity Causes Printer Reset
The frame of the black power supply is connected to the ground in the wall plug via the power cable and the power supply frame is connected to the enclosure. With the various surface finishes, there's a chance that's not true in practice in all cases (but it should be). - emphasis added
To test this, I pulled out a multimeter and did some tests. The power supply case (black) is indeed connected to the ground pin on the power connector. However, my enclosure is _not_ connected electrically to the power supply. The power supply is connected to the backing plate (starting in this step), so the backing plate and the power supply are electrically connected. The backing plate is then attached to the enclosure (starting on this step), but only using the plastic rotating pieces. The top is held to the enclosure magnetically, through a printer part. There are no electrical connections from the power supply to the enclosure.
For completeness, I even tested whether there is continuity around the enclosure itself (in my case there is not). Each edge piece of the enclosure can potentially be electrically disconnected from its neighbor, as the pass-through holes for the screws are coated. The threads to connect the enclosure are on the piece connected behind, and everything looks like it is floating by itself. One way to electrically connect the entire enclosure to itself would be to insert these between the sheets when assembling.