That’s new information!
That wire is usually the cathode return wire and is connected internally in the LPS to FG. Verify that it is connected to FG with a DVM.
Your ma meter goes in series with that blue wire.
Please explain why your drawings are showing a different LPS than the pictures show???
Sorry, i pulled that off the k40.se site, was trying to figure out how do you wire the ammeter in
I don’t think the OP know the meaning of series or parallel circuits. Seeing what was drawn I don’t believe the OP knows what an electrical wire actually does so this really is more of an effort of literal steps. ie cut the blue wire, expose the copper of the 2 cut ends, connect the copper to the 2 terminals/connections of the Amp meter, etc.
It scares me when I see someone draw a circuit like what was drawn and is inside the electronics bay of a laser cutter.
hahaha… i do understand what and how circuits work… and i drew the circuit on microsoft paint… just because i don’t use fancy software to draw a schematic diagram, it doesn’t mean i’m an idiot.
We need to step back and understand what you are trying to do?
If you are just trying to add a 30 ma laser current meter to your new machine, you simply add it in line with the blue wire.
But your previous post asked how to add a laser test button…
Now your latest drawing shows the Main Control Panel that if it matches the photo is a digital control panel. That panel already has a laser test button so why are you adding one?
I do not see any reason to change any of the wirings of this new machine if you are just adding a meter. Just add it in line with the blue wire? If you need a detailed explanation of how to add it inline let me know.
AJ, you drew a circuit with an amp meter in it AND you included a circuit trace bypassing the amp meter.
Nobody called you an idiot, just lacking the understanding of electrical circuits. Terms like “in series” are terms used in describing certain ways of connecting circuit components and you seemed to have missed that.
Maybe this will help… The black wire is your blue wire…
Wire (green arrow) comes from cathode to positive side of meter (red arrow).
My ma meter is just spliced in. The side going to the supply is the meter negative and the one from the tube the positive…
Yes, because @donkjr said:
The milliamp meter is wired in series with cathode and ground. Specifically the FG ground pin on the LPS.
“laser cathode ----->+METER------> FG pin on LPS.”
that is why i asked again multiple times for clarifications… it was a simple misunderstanding because (which i later realised) Don was under the impression that my LPS did not have an L- … and I was trying to figure out how (with his explanation) put the whole thing together with the L- on my machine…
yup, that’s how i did it.
I’m changing my digital meter to an analog one
Ignore the 50mA meter… they sent me the wrong one, so I’m waiting for the replacement 30mA one
This is how you are confusing people (me).
This picture does not seem to be the same:
as this schematic protrays???
BTW your new panel is missing a LASER ENABLE switch?
No it is not, only thing in the picture that’s connected is the ammeter and the water temperature gauge. The scheme is my reference to what the original wiring and layout is before i hack it all up.
Would i really need one since the original panel did not come with one?
Sorry, my bad… my replies were all over the place and the images that i was sharing wasn’t what my of actual. will try to be clear and concise
Your right I see that your original digital panel does not have one. The digital panels I have seen have one. Evidently another ugly change in that panel’s design.
The enable function is implemented by logic internal to the digital panel.
This post explains the digital panel: Don's Laser Things: Understanding the K40 Digital Control Panel???
Without the digital panel, you need a function that enables/disables the laser.
Everything you need is on the drawing I gave your for your supply including a Laser Switch (laser enable) and a Laser test both of which you need if you are replacing the digital panel.
I suggest modifying this drawing to show your actual wiring that way we will stay on the same page :).
ok cool, will incorporate it into mine.
hehehe… will do
hey guys, sorry been pretty busy the last week… down with the flu and i got married… lol
anyway, here’s my wiring diagram that i’ve worked on, haven’t hacked it up yet, but this is what it will be. Appreciate the comments.
Before:-
After:-
Btw, please forgive me if i’m not using the appropriate symbols in the diagram… 
The way you have it the Laser Switch shorts out the interlock circuit.
The Laser Switch should be in series with the interlock circuit.
The last two connections on the LV (5V/24V) board have ? on them, how do you know where to connect them.
The L signal is routed through the LV board? Not sure why, simpler wiring perhaps?
hi I enter this discussion as I am waiting for the same machine, starting from the last scheme posted for the conversion to analogue if I wanted to change the m2 nano card with a dlc 32 v2,2 that I have at home for other things besides having the drivers and maybe an external 24v 10A power supply how should I make the connections to exploit the pwn in ligthburn?
on the circuit above we quickly tried to make a mks dlc 32 2.1v work instead of the m2 nano but we cannot go beyond 13mA with the tube, all having connected:
G-WP
-Spingle / TL
gnd mks-G
so the machine in lightburn works but with 100% power it shoots only at 13ma while with M2 nano it reaches 100% at 23ma what am I wrong?
