Endstop Mechanical Limit Switches with LED

Mostly Printed CNC - MPCNC Troubleshooting
1

HI!
My assembly is based on a Ramps 1.4 board and has dual end supports. I want to use in my design this end stop
Tell me what changes need to be made in the firmware for correct operation?

2

I think you should be able to use these as mechanical switch endstops assuming you can do without the LED indication. The switches for dual endstops are normally wired in series for each axis (2 switches per axis for X and Y) using the common and normally closed NC pins. No firmware mods are required but check to see if the default is normally closed. I think it should be. Hope this helps and welcome.

3

If your doing duel endstops then you just need to plug them in, just make sure you get the polarity correct or you will fry your ramps

4

Assuming you got your firmware from V1 release, no firmware changes are required. For some reason, only the dual end stop version of the firmware is available for Ramps boards, but I’m told that this firmware will also run serial setups. Some notes:

  • Assuming you have a Primo build, the trucks have mounting holes for bare limit switches. With the switches in your link, you will have to figure out some custom mounting strategy.
  • Switches are wired in parallel with a pair of wires from each of the four switches running to the control board.
  • Switches should be wired normally closed. This is what the firmware expects.
  • Polarity of the signal and ground pins does not matter
  • As long as you are careful to only use the signal and ground pins, nothing you do in experimenting with these switches will hurt your control board.

More information than you asked for.

Edit: I poked around a bit more. It appears that these switches wire up to +, -, and S. See this image.. What I don’t know is if the S line is setup for Normally Open or Normally Closed. If it is Normally Open, you likely have to rewire the connector so the yellow signal line goes to the “X Not Uses” in the connector. Alternately you could change the firmware to expect Normally Open switches. This is a simple change, but it does have consequences. The default of Normally Closed is done so that if a wire is knocked loose, homing will just fail. If the switches are wired Normally Open, then the homing will continue to drive the trucks until power is cut. If you want to skip the leds, you can wire them up as two-wire limit switches.

5

Yes, I use other endstop mounts.
Yes, at the first start I cut and re-soldered the tracks on them.

6

I used that same style of endstop switch on my build. I set them up in dual-endstop mode (for auto squaring) and haven’t had any issues with them. One thing to keep in mind with the endstop mounts is that if you ever plan on cutting metal you need to enclose them. Otherwise the metal shavings will (eventually) short them out.

Link to where I used them in my build: Build in Progress in Maryland

1 Like
7

Oh, thanks for the advice.
Yes, I will make lockers to protect the stop ends.
So nothing needs to be changed in the firmware?

stopend
stopend859Ă—692 166 KB

8

Here is the setting from my firmware:

// Mechanical endstop with COM to ground and NC to Signal uses "false" here (most common setup).
#define X_MIN_ENDSTOP_INVERTING false // Set to true to invert the logic of the endstop.
#define Y_MIN_ENDSTOP_INVERTING false // Set to true to invert the logic of the endstop.
#define Z_MIN_ENDSTOP_INVERTING true // Set to true to invert the logic of the endstop.
#define X_MAX_ENDSTOP_INVERTING false // Set to true to invert the logic of the endstop.
#define Y_MAX_ENDSTOP_INVERTING false // Set to true to invert the logic of the endstop.
#define Z_MAX_ENDSTOP_INVERTING false // Set to true to invert the logic of the endstop.
#define Z_MIN_PROBE_ENDSTOP_INVERTING true // Set to true to invert the logic of the probe.

If you are going to be using a touch plate for setting the Z axis, then you want Z_MIN_ENDSTOP_INVERTING set to true. A setting of “true” is a NO connection. A setting of “false” is a NC connection.

9

Do you also have this stopends with LEDs?

10

No I don’t. All that matters is whether you wire them NO or NC. As mentioned previously, NC is what the firmware is expecting with all the “false” values, but you can change the firmware to expect NO switches by editing the block of code you posted (with the added risk I mentioned of using NO switches).

11

Thanks :+1: