This is part 2 of the RoboElectronics X2 CNC controller project.

Now that the power supply for the stepper motors is inside the controller enclosure lets go on.
The rest of the electronics placed in this controller need some power to.
Therefor I have placed another switching power supply 12V 8,5 Amps.
This will power the secondary side of the XD14 breakout board (See part1).

12V 8A 100W power supply

But as I told you the breakout board is isolated, so also the PC side needs some small power.
So I had to place a USB connector in the back panel of the  CNC controller.
You can also choose to place the breakout board directly on the back panel of course.

USBa for XD14

In the front panel will be a power switch, but this switch can only transfer 6Amps of current.
The solution to this is to use a SSR (solid state relay).
This is basically a normal relay but without moving parts ‘solid state’.
So with a small voltage and current I can now switch 24~380Vac at 60Amps.
I will use 2 SSR’s as I will also start and stop the spindle (kress 1050FME) from the software.

60A Solid state relay SSR

Here you can see the two power supply’s the two SSR’s and the shunt for the panel meter.

Power supply's and SSR's

Now it’s time to introduce you to a new feature… And again just an extra, and not needed to run CNC.
The PoKeys55T from poscope.

PoKeys55 is an easy-to-use USB device that combines standard keyboard and joystick simulation,
and does not require complex programming knowledge.
Pokeys55 provides 55 digital I/O (5V tolerant), 5 analog inputs (10-bit) and 1 analog output (10-bit).
All the I/O is controlled by the provided software.
PoKeys55 can be used as industrial or CNC control, custom joystick or keyboard or data acquisition board.

Why do I use this? Well because I already know I will make a pendant in the future.
And I will use is to drive a 4×20 display in the front panel.
What will the display show? Don’t know yet 🙂 but I like the extra’s haha…lol
For more info on this part, and the datasheets etc. checkout the poscope website.

pokeys55T USBb for PoKeys

I routed out a piece of acrylic and mounted the breakout board and the PoKeys on it.
This way I could place it on top of the SSR’s to save valuable space in the way to expensive enclosure.

Breakout board + PoKeys55T

The display that the pokeys can drive must be one of the HD44780 chipset.
I will use a 4 row 20char display, blue LCD 4×20

Mains power connector used is type Neutrik NAC3FCA and Neutrik NAC3MPA.
The mains power out for the spindle is the Neutrik NAC3FCB and Neutrik NAC3MPB.


That’s it for part 2, in part 3 I will be making the front and back panel for the enclosure.




    • Robo Says Beantwoorden


      Thank you for your advice, although mine is working really fine, for a long time now with daily use…
      But well maybe im lucky…

      I really use the kress for hours and hours and are using the second set of brushes now.
      Never had any trouble with the ssr or the kress it self… By the way, this is the 1050 FME with the 27000 rpm circuit board.

      best regards

      • nophead Says Beantwoorden

        I have a Kress 800FME and an identical looking relay. It has the same manual as 1050FME so I am surprised its electronics are significantly different but they must be if yours works.

        • Robo Says Beantwoorden

          I also do not think the electronics would be very different…
          But really i have had no troubles at all, and think it is switched about 1000 times or so 🙂

          Maybe nice to know that kress does sell the circuit boards as spare parts as i recall.
          Maybe something that could be different is that my kress is still grounded to earth.
          And i use 230V so no 115V (not sure what you use)

          • nophead Says

            240V here in the UK but mine only has a two core cable, so the only earth is via the router frame.

          • Robo Says

            Same here…. but the router frame is connected to earth…
            Really not sure if this has something to do with it.
            If the machine is still not to old, you can send it to kress for repair..
            At my first one the shaft broke within a view months of abuse, but the did not even ask anything, just shipped a new one straightaway

          • nophead Says

            BTW, the leakage when my SSR is off is enough to make the Kress buzz.

          • Robo Says

            Think there is your problem… the SSR…
            Mine is ON or OFF no leakage or buzz whatsoever..
            The Kress has a softstart circuit, i guess that circuit does not like it when you supply a fraction of the needed voltage.

            For further conversation i would suggest to email me to prevent this page from clogging.

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