Thunder Laser sent out a few relays to some 2.x folks. The relay attaches to pin 3 on the I/O terminal block. The relay is sync'ed to a running job. You can use this to run your assist air whenever you run a program, for example.
This is the relay that they sent to me.
I thought it was a really nice option, but I had a few issues with the this board that made me decide to roll my own solution.
- I really did not want to mount another device to my electronics module and the wiring looked simple, but busy.
- I am not a big fan of these little relays. I prefer DIN rail versions that are cheap (<$10), easy to replace and resize.
- I don't like the +5 and Input (AC) on the same terminal block. I am sure it is fine, but in addition to running an Engineering department I also run a PCB layout group. We deal with a lot of international safety agencies and I know this would not meet UL or CE creapage and clearance rules. I am sure it is fine for DIY use, but old habits die hard.
The relay is rated for 240 VAC, but you could use this to fire a DIN relay using 24V if you are concerned about the safety issue I mentioned.
I did this simple little mod to my 4 axis controller. I made a little Pololu compatible relay driver. This uses the same signal to fire a 24V DIN relay. It really makes a clean setup because all the voltages are already on the driver board. It is one wire (bottom white wire) to the Thunder Laser DSP and 2 wires to the relay. I will probably have a bunch of these boards made. I only partially stuffed this board for initial testing. I will probably put two drivers on this board (one on step and one on the dir signal)
When you power up the laser, the relay engages right away. Since the relay is form C contacts (SPDT), you can put the device under control on the N.C. side. When the job runs the relay disengages which can turn on/off your device.
The feature is control using the "Is Blowing" check box on the Manufacturer Settings page. This is nice because I don't always use air, like on glass jobs or anodized aluminum. I don't like the noise.