estop

[sick2]

Having the e-stop cut the mains power should really be avoided for a number of good reasons.

James

What are the reasons for this? I currently use an relay which I can switch on/off with the E-stop. Keeping in mind it only will be used to in case of an emergency.

[andy_con]

What are the reasons for this? I currently use an relay which I can switch on/off with the E-stop. Keeping in mind it only will be used to in case of an emergency.

cos it can take half a second or a second for the power to discharge so galvos drop, beam wonder, hit people in the face etc...
power discharge isn't instant

[norty303]

The best bet if you're cutting power is to just do the laser supplies and not the galvo supply which is how I believe Rob's distribution board works and is designed to work with the interface board. But it's the time to stop and cap discharge that I think is the primary reason. That said, a shutter would shut quicker anyway, but not all projectors utilise a mechanical shutter.

[frostypaw]

Ah cheers about the key, though it might be.

Using the stanwax ilda's interlocked relay on the output side of the diode driver's supply seems instantaneous.

[norty303]

If you're switching the DC then you may have better results.
I used them on big projectors where I needed to switch off multiple reasonably large PSU's so that wasn't an option unfortunately. I had to switch the AC for everything bar the scanner supply.

[Draco]

I wanted to pass this by you guys as well, the e-stop i am working on would kill the power to the lasers and not do anything to the galvo supply, my lumia projector already has this via an RF remote that is running at around 433mhz i think, the remote is needed to turn on the device as well, i did that so some one could not accidentally turn the thing on with out me being there, the other e-stop is the same that's used for robots it's a self locking button that needs to then be turned to reset it, i still need to build the cabinet for it and i currently dont have a suitable box, any one have a supplier that sells project boxes that are fairly rugged? all i have is the cheap crap you can get from radio shack, it works fine for my Tesla coil but would rather have something a but more rugged https://www.sparkfun.com/products/11366
that's what i had in mind, i have been using one for my home theature , it takes the 12 volt signal from my avr to turn on my main power amp and the power amp for the sub, it seems built well enough and the red color i like for something like an e-stop.
it has to be cheap in cost as well, i don't do public shows and only display with a small group of friends