Controller Board Package opened and does not fit on frame

My controller board package was not sealed, instead opened.



Source:
mustun.ch/michael/2013/08/08 … ot-sealed/

It is normal that the package was opened, as it is produced and programmed in different facilities.
We will check into the fitting issue. It is strange, as nobody ever complained about this, and all boards are the same.

Ok, thanks for your information about the package. Good to know.

Maybe if you use brute force it can fit… but it can damage your PCB board.

[quote=“VEL417”]It is normal that the package was opened, as it is produced and programmed in different facilities.
We will check into the fitting issue. It is strange, as nobody ever complained about this, and all boards are the same.[/quote]

With my board, the smallish plastic washers were exactly the same as in the pictures posted by “flag”.
The circular “stand off” doesn’t fit into the board holes.

This part actually is designed for isolated mounting of semiconductors in TO-220 package to a heatsink.

Maybe including true plastic washers instead would be an improvement.

Also, the slotted mounting screws are too long, I had to shorten them for about 2mm.

Then, the circular “stand off” gets pressed enough for a tight fit.

By the way: Is it by design that the printer’s metal frame is not connected to ground? Wouldn’t that be some kind of improvement, EMV-wise?

[quote=“clm”] […]
By the way: Is it by design that the printer’s metal frame is not connected to ground? Wouldn’t that be some kind of improvement, EMV-wise?[/quote]

Right, just flat normal spacers will do the job!

Oh, you are right! This is a real electric shock problem.

Please note that the kit is running from 15VDC, coming from an isolated power supply.
There is absolutely no risk for and electric shock.
Grounding is not required.

Grounding is surely not required for reasons of electrical shock.

But it might improve the printer’s EMI behaviour; consider that there are relatively high pulsed currents in use to drive the stepper motors, and that these are connected to the driver circuitry via unshielded ribbon cable, for a length around 1 metre.