Wiring dust collector to automatically turn on.

[Mike Chan]

Hi,

I wanted to see if anyone has tried wiring their dust collector to turn on once their laser starts engraving? I'm running a Trotec Speedy 300 and Penn State Industries dust collector. I'd like to build an enclosure for the dust collector, to reduce the noise, but turning it on would then be a hassle.

[Dan Wilhelm]

It should be possible just by using a signal from the Trotec to switch a relay rated for the current draw of the dust collector. The problem will be tracing down a signal on the Trotec control board to use...then the nerve-wracking process of tapping off that signal. Unless you have experience working on sensitive electronics, I'd probably just put a remote switch on the dust collector and turn it on when you are lasering.

[Scott Shepherd]

We used a remote control for that for years. We had the same thing, a dust collector shrouded in a box with noise suppression foam inside and carpet on the outside. It worked pretty well. Just velcro'd the remote to the laser, just hit the on button when you're ready, off when you're done. Now, we have switches on the table next to each laser. Just flip the switch.

[Dan Hintz]

I'm running a Trotec Speedy 300...

If you're electrically inclined, there's already a trigger signal coming out of the back of your machine (look for a round 5-pin connector)... I'll leave the rest up to you.

[Dave Sheldrake]

Door switch maybe?

cheers

Dave

[Gary Hair]

My laser has an outlet that is fed by a separate input that is for that very purpose. I haven't used it except for the first week I owned the laser - why? Because I always want the exhaust to run for a while after the job ends and there was no way to program that in the driver, it's on when it starts and off when it stops. Since it's outside I use a remote to turn it on instead, that way I have full control over it.

[David Somers]

I use a remote on the dust collector at my lathe. Works great. A small fob turns it on and off wirelessly. 110V. I think I got mine from Woodcraft on sale. But any of the woodworking stores will carry them. Simple, no wires to run. And if you have too much between you and the receiver to work you can always return it.

Dave

[Gerd Spatz]

Hi,
I wanted to see if anyone has tried wiring their dust collector to turn on once their laser starts engraving? I'm running a Trotec Speedy 300 and Penn State Industries dust collector. I'd like to build an enclosure for the dust collector, to reduce the noise, but turning it on would then be a hassle.

I use a simple master-slave power strip with my Universallaser.

[Steve Morris]

the 300 has the output connector on the back and JCX has a programmable start/stop delay for it. Trouble is getting the pin functions/voltages as I think its a 2 way control method.

Sorry for the dupe but I asked this question on another thread before seeing this one.

[Michael Reilly]

My old Speedy 500 had a 5 pin connector that was "proprietary" though they provided one to me. It was meant to connect Trotec's exhaust fans that they don't sell in the US. Pins 1 and 2 will work to trigger a fan, however it's limited to 24VDC 100ma and is meant to be purely to flip a relay. The contactor we used to drive the fan had the potential to draw more than that so we actually had a relay before the contactor.

It worked, HOWEVER, it's important to note that motors have a starting coil and a running coil. The starting coil draws more current and is used to get the motor spinning. There is a centrifugal clutch that toggles once it's spinning so it is using the running coil at a lower current to keep running. While motor companies don't seem to publish it anywhere (my electrician called and asked), motors (particularly large ones) are rated for only so many "starts" per hour. Ours was rated for 2. We didn't know that, so we would do a test cut to check settings, tweak, run again, etc. So it was starting/stopping multiple times within 10-15min. After 6-8 months, it would draw so much current, it tripped the breaker. We found we could wind a rope around it, pull to get it spinning and then switch the power on and it would run. Thus, the starting coil was fried. At that point, we didn't know why, so we replaced it with a heavy duty extreme environment model motor and went on as normal... only when it started to misbehave did we figure out why.

The ideal solution would be to add an off-delay with reset. So whenever the delay timer loses signal from the laser, it starts a countdown of say 10-15min before shutting off. If it gets a new signal before that time, it clears the timer and runs as normal. I didn't know the terminology for this at the time so I didn't find what I needed, but I think such things exist as plug-in modules.

Our solution -- especially since our motor coil was already damaged -- was to put a Tee fitting on the motor inlet which was in a shed outdoors. One end of the Tee went in to the laser, the other end had a motor driven HVAC damper that would open/close under motor power. I laser cut some reinforcement for the rubber seals to compete with the motor suction. A circuit was setup such that when the laser said it was running, it would close the damper outside and draw from the laser. When the laser stopped, it would open the damper, and since it was right at the motor, it would more easily draw air from the outside and just recirculate it through the motor. This reduced noise and air conditioning loss inside. We would just start the motor in the morning and run it all day in this manner.

On our new equipment at our new location, we have 3 phase power, so while we're currently using the mechanical disconnect as a switch, we will eventually add a VFD to control fan speed. Vytek added a wire we can plug into a VFD so the machine can control the speed, so it can ramp it down slow when not needed and speed it up when it is, but never actually have to stop/start it. It achieves this (I believe) by just sending 3, 6 or 9 volts to the wire. The VFD has a reference 10volt pin that is meant to be run through a variable resistor to a sensing pin. Turning the knob would vary the voltage and you can have it adjust the speed proportionally. So I believe we would skip the reference voltage pin and just send the sensing pin the voltage from the machine. That's how I understand it anyway...

FYI, you can run 3-phase motors up to 1 or maybe 2 HP off 220 volt single phase and still control their speed with the right VFD. We're doing that on our paint booth simply because it was a long distance to run 3 phase from the main panel vs single phase from a nearby sub-panel. Not that you're supposed to put a VFD on a paint booth, but we actually do very little painting, we're mostly using it for fume extraction while gluing acrylic and that doesn't require as much airflow.

[Chris Gerber]

If you are unsure, or uncomfortable tapping into a signal from your machine controls (simplest method if available), perhaps adding another microswitch to the home position of the X or Y axis (whichever is easiest for mounting) would do the trick for you. Wiring this switch to an OFF Delay timer, then from the timer to the start circuit of your exhaust system, would allow you to keep the exhaust system on for an adjustable amount of time after your engraving job has completed (assuming X and Y axis returns home at end of job).

Chris...

[Tim Bateson]

Lowest tech solution is to plug both into the same power strip.

[Michael Kowalczyk]

I have a Heavy duty light switch that controls the dedicated receptacle. It's as easy as turning on a light.

[Dennis Rech]

Hi,

I wanted to see if anyone has tried wiring their dust collector to turn on once their laser starts engraving? I'm running a Trotec Speedy 300 and Penn State Industries dust collector. I'd like to build an enclosure for the dust collector, to reduce the noise, but turning it on would then be a hassle.

I believe that you are looking for a current sensing relay.
Pass one leg of the laser power cord through the sensor.
Break the fan line cord and hook in series to the two relay wires.
When the laser comes on, the current flow is sensed, the relay closes and the fan comes on.
Everything is isolated from everything else.

Grainger sells a bunch of different styles.
Here is the part number of one.
Item # 21EU14

Select for the loads.

Hope this helps,
Dennis

[Jacob Davalos]

I want to achieve this, but instead of dust collector I want to turn on my air compressor for air assist, only when cutting.