Lightobject.com Support Forum

I'm making good progress on my laser build.

Two AWC608 related questions:

1. Is it OK to power the AWC608 from a 12V supply? I will be using 48V for my steppers, and I have 12V handy in the machine for the DSP.
The DSP appears to be happy sitting on the bench, drawing about 200ma @ 12V, but I don't have enough of the machine assembled to try it for real.


2. Where's a good place to attach things like the E-Stop button and the interlocks for the cover?

It seems kind of silly to stick the interlocks in the "protect" loop for the chiller, but maybe that's how it's done. On an Epilog, if you open the cover it disables the laser but the XY still moves. So, having the interlocks force TL to be deasserted would have the same effect.

The E-Stop might be the one to put in the interlock loop. OTOH, maybe E-Stop should just kill the power to the DSP and the laser PSU.


/Mitch.

My e-stop (we are talking about the BIG RED button here, aren't we?) cuts the mains supply to the internal mains distribution board (socket strip) - this removes mains from the laser PSU and the 24v PSU.
It does NOT stop the water system, the fans or lights from working (commonest reason to hit it in a hurry is unwanted flames so exhaust and a chance to see where they're coming from is important!).

Hi Nick,

Thanks -- this is along the lines of what I'm thinking as well.

I'm planning to use an Arduino or other micro controller to serve supervisory functions, including:

- Interlock switches for doors (to disable but not power off laser)
- Temperature sensors before/after tube
- Coolant flow rate sensor
- Laser power ammeter
- Motor disable to geckos
- Red dot on/off
- Relays for air assist, chiller, exhaust, laser+stepper PSUs, DSP.
- interior LED lights

Software will do most of the logic (hour meter, power up sequencing, over temp detect, coolant detect, and maybe E-Stop). The micro controller will be powered all the time. If I get really geeky I'll have "user IDs" to log laser on hours per person.

Trying to figure all this out, I kept trying to match the AWC608's pins to useful functions that need to be supervised.

If I do a software E-stop, I'll kill the power to the DSP, laser, and steppers.

but I'm far from that point - I've got the basic x/y/z frame done (from scratch build, custom design), just making plans for what goes in the electronics bay at this point.

Thanks!

/Mitch.

Mitch
Occam He say KEEP IT SIMPLE!!!
IMHO, forget Arduino controls (you bought the kit to engrave and slice stuff up, not to give you a chance to play at coding!) and use simple switches, for example: Between the WP and ground on my PSU I have, in SERIES, a cabinet lid proximity switch (Maplin, Radio Shack etc window alarm component costing pennies), a water pressure on/off switch (eBay, £3) and a switch which is the spare line of a DPST switch turning my water cooler on and off. No Arduino needed here.
The rest is just about equally simplistic.
All, naturally, merely my opinion...

NickWL wrote:Mitch
Occam He say KEEP IT SIMPLE!!!

Ha! Excellent advice. Keep an "I told you so" in your back pocket, you might need it!

IMHO, forget Arduino controls (you bought the kit to engrave and slice stuff up, not to give you a chance to play at coding!) and use simple switches, for example: Between the WP and ground on my PSU I have, in SERIES, a cabinet lid proximity switch (Maplin, Radio Shack etc window alarm component costing pennies), a water pressure on/off switch (eBay, £3) and a switch which is the spare line of a DPST switch turning my water cooler on and off. No Arduino needed here.
The rest is just about equally simplistic.
All, naturally, merely my opinion...

When I get around to actually firing the laser, maybe in a month or so, it'll definitely be simple.. at first.

The basic problem here is that I'm an embedded systems software/hardware engineer (so I code for a living). The first thing I think about when X needs to control Y is "computer." The main purpose of the laser cutter (just lightly ahead of cutting and engraving) is to see if I can design and build it in the first place. (amateur machinist here).

/Mitch.