I am trying to find out the best way of running an e-stop. I live in the US and trying to find the specific rules for how an e-stop must function seems exceptionally difficult. No amount of googling “laser projector e-stop rules/regulations/etc” seems to yield good results. Seems like many people build their own. The lasers I own have an ethernet estop (2 bridged pins).
I found this product GAGALIGHT-SAFETY Unit LASER E-STOP but it appears to be only a single button, and I don’t know if a single button is allowed? Some others I’ve seen feature a key switch, an emergency button AND an arm button.
Additionally, it would be great if this could be run over the same ethernet cable as the data signal, but again that seems to be problematic in implementation depending upon if you’re using megabit or gigabit. There are spare pins over ether net at megabit speeds but it seems that gigabit doesn’t have them.
Other options I’ve seen are running it over TCP/IP and having a sending device (the estop remote) and a receiving device (at the laser end) that send a constant stream of packets that are required to keep the shutter open on the lasers (either by a shutter control pin over ILDA or a power relay to the projector), and if the packet stream stops then the shutter closes/powers off. This seems like a nice solution as it can run over ethernet.
Currently I am using a helios DAC but plan to upgrade to etherdreams.
Looking for advice on the best way to achieve a safe, and compliant estop mechanism that ideally doesn’t involve running a separate cable to the projectors.
Commenting purely on the compliance side of things, here’s what you need for a remote stop in the US for a class 4 laser system (500mW or above)
Must fail safe - if the remote stop is disconnected because someone tripped over a cable the laser systems must attenuate
Must require actuation of a reset command - if the lasers lose power or the remote stop becomes disconnected and is then reconnected, you must have to press a button/turn a key/do any specific action to then re-enable the laser systems
There must be a delay to this reset function - The length of time for the delay is up for debate, but typically it is 4-10 seconds
Separate important things from the remote stop:
your laser system must have an emission indicator that is illuminated whenever the laser is capable of emitting, not just when it’s actively emitting
there must be a captive key switch. Most of the time people have this both on the laser and on the remote stop, but technically it is legal to only have it in one location
make sure your system is varianced and has all the required labeling
Not for nothing but these are all things your laser manufacturer should have already handled. It shouldn’t be your job to make your laser legal unless you built it. If they didn’t… consider where else they may be cutting corners and maybe look at a few other manufacturers.
I’m biased because I am a manufacturer, but there are several that do things the right way and support their users well.
So theoretically I could build a system out of two nano controllers like an ESP32 with an ethernet port, and write some software that expects to receive a stream of packets at a given rate, and if said stream is interrupted either by the switch or by disconnecting the e-stop, the device shuts off the projector?
I can’t speak about the legality of that but I have done it myself in the past. I would personally suggest adding some kind of additional circuitry that can detect if the MCU crashes and disengage the interlock relay!
For systems you intend to resell, you’d need to provide enough evidence to FDA that this system is compliant and reliably fail safe, which is a much bigger problem to solve.
Your original thought of controlling the interlock over spare conductors in the ethernet cable pushing data is a good one. You absolutely don’t need gigabit ethernet for a single laser.
The problem here is that it sounds like your laser only has two conductors required to satisfy the remote stop, which means if it’s class 4 it is inherently a non-compliant system under 21CFR1040.10.
I’m not the laser police, just letting you know that if you’re doing public shows in a jurisdiction that does inspections and checks these things not having compliant lasers is going to cause problems for you. It sounds like you’re pretty technical, if your systems do only require the interlock be closed you may want to rewire them to require the reset function as well, but also doing that means you’re now legally the manufacturer of the laser and need to file a product report with FDA.
It’s messy. If this is for personal use, generally i’d say don’t sweat it just be safe. If it’s for commercial use though, make sure you have all your ducks in a row. Especially if you’re doing shows in NY, AZ, TX, Cleveland, Portland Oregon, Chicago, etc.
I was told by the manufacturer that they’re legally complaint and they list a document on the product page above, however I have no way of verifying if that is the correct document for variance etc.
You can see from the photos the interlock has an RJ45 connector in it with a bridging wire.
Sounds like you are definitely in the know about this, would you mind taking a look?
So… I’m a competitor to Emma so I am going to be a bit vague in some of this. I have had no personal dealings with Emma, so I assume they would do things in a way that is fully compliant and legal.
The system as you have described it is absolutely not compliant with 21CFR1040.10 or IEC 60825-1. Given that Emma states the system is compliant and they are self attesting through that CE attestation document that the system is compliant this is clearly a manufacturing error that somehow escaped QC. I’m sure that’s an accident they would be happy to rectify.
Also, if you do not have a variance, you were supposed to have one prior to them shipping you these systems. I’m sure this was also an accidental oversight on their end of things and that if you contact them to resolve it they will do their best to help resolve it.
If anyone here that isn’t a laser systems manufacturer has had any dealings with Emma they may be able to comment a bit more freely on this.
Right now I am only using these lasers for private use, but I am looking to see if it’s possible for me to get my variance to use them for shows. Loving Liberation.
So private use is legal without a variance, but sale of those systems to you without a variance is not.
Again, I’m not the laser police and have no interest in that, as long as people are being safe I’m happy, but it was Emma’s responsibility to make sure you had a variance prior to sending those out and there is a risk of future systems being seized by customs without that in place
In order to get a variance for these you’ll need Emma to file a product report with FDA. You can file it yourself as well with yourself as the listed manufacturer since as the person bringing them into compliance you would be the manufacturer as far as FDA is concerned
I am working on getting my variance so I can use lasers commercially. Maybe I won’t be able to use these ones if I can’t get Emma to get variance for them, always difficult dealing with Chinese manufacturers. Will report back my progress as it develops.
In talking to FDA about a few other things, this topic came up and I asked about Emma (without any specifics) and was informed they are on the import ban list for non-compliance. Import Alert 95-04
How many e-stops are used in a typical laser universe? I have one setup foh with me, but I’ve been thinking there should be at least another one setup for access in the wings area too. I am not ILDA safety trained and have never worked with any professional laserists.
The number of e-stops used on a show largely depends on the scale of the show. If your operator can see where everything is terminating then one is fine, if it’s large enough that the operator can’t see where everything is terminating and you have a spotter, they should have one too. The most common setup we see with our users is two e-stop pendants just like you describe there, one at front of house and one in the wings. These are chained together so either pendant can shut down the lasers