Hello! I run the laser shop at ForgeGreensboro.org community makerspace. We have multiple lasers all hooked up to a central exhaust. At the moment we are operating blast gates by hand to concentrate exhaust on the machines that are actually running. A fancy new exhaust system is being donated to us and it will include motorized blast gates!
My question is how to wire them up so they can open and close automatically when you turn a machine on and off. We’ve got three Ruida based machines, one Trocen based machine, and one Universal laser. We have a mix of brand names (Thunder, Boss, Universal) and two generics. I don’t yet have specs on the motorized blast gates, but I assume they’ll be powered directly from the wall and will just need a low power (5v?) signal to trigger them on or off.
Has anyone else worked with such a system, or set one up? I’d appreciate any insights anyone might have. Thanks!
I have not done anything like this but thinking logically about it, all lasers have an E-stop switch, so maybe wiring the blast gates into their E-stop wiring may be a possibility.
There’s no way to hook a system up like that. I would think again about your options because this is going to cause a ton of probs.
The flow needs to be consistent. Even if you had two identical machines with the exact same tubing, a single speed suction fan is going to operate totally differently with one port vs two open. In theory, you could have a complicated system with a variable speed motor (generally needs to be continuously variable 3-ph vfd or BLDC) and some engineering expertise to make that flow work.
But you have different machines with different requirements for flow. I can say for sure a ULS requires significantly higher static pressure on its plenums and as such will probably never be able to operate in parallel on a shared pipe like that.
Can you share the info on the system you are getting? I can look it over and see what the options might be
We currently have a system with an industrial blower outside, and ducts going to the four currently-online lasers, each of which has manually-operated blast gates already. The blower is on a dial (rheostat? potentiometer? not sure) which we adjust as needed. The new system will mostly be replacing cheap aluminum hoses and other “what we had lying around” wyes and other parts with custom built ducting. There is a weighted butterfly on the end of the central duct, which I imagine might address your concern, at least in part? But exhaust systems like this are not my area of expertise.
With similarish ones, but those ones have been for woodworking equipment that had mandatory electrical brakes and/or frequency converters installed, so the pneumatic solenoids got their control signal directly from those.
That said:
All of those lasers at least look like industrial machines, so it’s hard to imagine there’s no run/stop signal output on their controllers (or power supplies) I/O connectors.
If there really isn’t, a simple current transformer and relay with an adjustable current treshold will do the job.
Or just a low voltage swithch for the gate.
There are fancier solutions out there as well, but since it’s just a few gates, at least I wouldn’t overthink it.
Any exhaust system that is desgned to have multiple branches with automated blast gates will most likely have a frequency converter driven fan, and a constant flow control.
If not, both are relatively cheap for such a simple system.
It’s possible, especially if there’s bellows and/or movement dampers as well, but usually those butterfly assemblies are just backdraft gates.
Without bellows/dampers, opening or closing even one branch will cause the butterfly to ocillate, and to cause all sorts of headaches.
I have no experience with this, but looking at your requirements it seems like there is a simpler solution that may work.
You do NOT want to open the gates only when the laser is firing - that won’t clear the enclosure, and may have delays in starting up. What you specify is that the gate is open when the laser is “on”
Why not just use a master power switch for each laser - turning the master switch on would power the laser, and power the signal that opens the gate. This would be a universal solution. The only draw back is that depending on the machine you might have to switch the maser switch, and then turn on the laser.
You’d probably also want to control the blower - if any machine is on, the blower should be running.
Ran across this thread as I’m looking at similar solutions - about to run an exhaust system in our shop and will have blast gates for three input ports - one for an Aeon Mira9 (6") and then two 4" for an Xtool S1 and F1 respectivelly.
Have been looking at options for how to automate the blast gates as at least one will be located in a not so convenient location to open/close.
I ran across something mentioning GRIT automation today which looks promising. They gave servo motors/brackets that retrofit to existing metal gates and then wireless control from a hub. Not a cheap solution (looks like about $1000 for the hub, power supply, 2 4" and one 6" gate controls), but when is purchased automation ever cheap. Not clear yet how to have it automatically detect the lasers coming on - I with with the Aeon and a Ruida controller there are some options that they have that would work based on inductive current draw sensor (thinking it could sense the laser tube power) - but not sure of any options for the Xtools - other than remote switches that they have which would make it more convenient.
Steve - if you’ve found a solution since your posting I’d love to hear - I’m just down the road in Mebane - need to check out your makerspace sometime…
Ruida-flavor controllers have a Status status output that goes low when the machine is running a program, so a relay on that terminal would give you a cleaner signal.
Some controllers also have a configurable delay time before starting a job to allow blowers to get up to speed and another delay after stopping to let the fumes clear. A time-delay relay would keep the blower running even after the controller is done, which might be a better experience for the operators.
