How to include an indicator lamp in a limit switch circuit?

Hello to all:

I am building a Further Fabrication Y1200 from scratch. I have all my motion controls working, and limit switches are working perfect/as expected with my Ruida RDC6445S(EC) controller.

I want to add a small panel with DC bulbs that will light up when a limit swicth is triggered.

I have tried wiring a bulb in series with a limit switch using #1 GND and #5 Limit X+ on the CN4 grouping as an example…but now every time I press the limit switch while running a simple test program, the bulb comes on and the stop-motion command isn’t recognzed by the controller at all.

Sounds like I need a relay…but does anyone know what kind of voltage/amps that limit-signal produces? My voltmeter shows around 4 volts, but I can’t figure out the amperage.

Anyone have any ideas/suggestons? Thanks in advance!

4 Channel Relay Module Board with Optocoupler High & Low Module 5V/12V/24V Optional (5V)

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It’s unlikely you have six switches on your machine to accommodate both limit and home operation switches.

Ruida only watches the - inputs for home operation, once homed it then watches the + inputs for limits.

Red are home switches, green are limit switches.

These are all active low, so they only need to be pulled to ground to signal the Ruida.

Don’t fool around with relays, use the KISS principle.

Make sense?

:smile_cat:

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I use opto isolators. Stop any noise on the line and have red leds that light when tripped.

Very interesting, thanks for the information.

Here is the wiring circuit to use a LED with a switch:

There are many switches that already feature this design, you could remove the LED from the board and put some extension cables in between, that would be a quick and (very) dirty solution :slight_smile:

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There’s an interesting gotcha with Type C, the classic Makerbot switch sold by World+Dog: if you connect two of them in parallel (as you might for an Arduino controller), closing either switch shorts the power supply directly to ground through the other one.

You can wire all four Ruida axis inputs with Type C switches, because the inputs are not wired together, but keep it in mind for other machines.

They’ll blink invisibly fast, because the controller pulls the axis off the switch almost instantly, so the home position has the lights out. After homing, the Ruida controller will not let you jog the laser head far enough to bump the switches on either end of either axis.

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I figured it out :grin:

What are you doing with this Ruida? Are you attempting to use your home switches for limits?

I’m kind of lost here.

:smile_cat: