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View Full Version : Who has fire detectors specifically for laser?



Mike vonBuelow
10-23-2010, 5:56 PM
Seeing that cheap epilog 36 (http://www.sawmillcreek.org/showthread.php?t=125121) has got me really thinking about buying a dedicated detector....

who else has??? :confused:

Scott Shepherd
10-23-2010, 7:43 PM
My laser has one built in. It doesn't detect fire, it detects heat above a certain range. It sets off an alarm.

Joe Pelonio
10-23-2010, 8:27 PM
Not a bad idea, though staying with it while running is best. Maybe both!

Mike vonBuelow
10-23-2010, 8:58 PM
Right!

I do always try to stay with it...

Dan Hintz
10-23-2010, 9:25 PM
Same as Steve... built in.

Bill Cunningham
10-23-2010, 10:16 PM
My fire detector is 'me' If it's likely to burst into flame (cutting acrylic) I stand right there and watch it. If you see the orange flicker on the ceiling in the next room, yer uh.. too late:D

Robert Walters
10-24-2010, 1:29 AM
My laser has one built in. It doesn't detect fire, it detects heat above a certain range. It sets off an alarm.

That's it? Just an alarm?

Any option to shut down?
Any dry-contacts? (If you don't know what those are, nevermind)

Adam Orton
10-24-2010, 2:45 AM
I have a dedicated alarm and a fancy extinguisher with the Halon equivalent (350 bucks when the same extinguisher with the regular stuff was 32bucks.)

Mike Null
10-24-2010, 6:49 AM
I use a standard smoke detector but never leave the machine when it's cutting.

I've set off the detector with the table saw a couple of times but never with the laser.

Scott Shepherd
10-24-2010, 9:57 AM
That's it? Just an alarm?

Any option to shut down?
Any dry-contacts? (If you don't know what those are, nevermind)

I'm almost certain it shuts the machine down as well, but I didn't want to post that as I wasn't 100% sure that's what it does, but it's what I seem to recall being explained to me.

Even if it's just an alarm that's about 100% more than not having anything at all. I'd rather hear an alarm that gets me to run to the laser than just let it burn to the ground because I didn't know there was a problem.

Brian Fiore
10-24-2010, 12:18 PM
Anyone have a CO (Carbon Monoxide) detector in the same room as the laser, and ever get a high reading?

I just purchased a CO detector to be safe, in case the CO gets past the exhaust system.

Dan Hintz
10-24-2010, 12:24 PM
Anyone have a CO (Carbon Monoxide) detector in the same room as the laser, and ever get a high reading?

I just purchased a CO detector to be safe, in case the CO gets past the exhaust system.
:confused: What CO? How much material do you think your laser is burning?

Robert Walters
10-24-2010, 12:32 PM
I'm almost certain it shuts the machine down as well, but I didn't want to post that as I wasn't 100% sure that's what it does, but it's what I seem to recall being explained to me.

Even if it's just an alarm that's about 100% more than not having anything at all. I'd rather hear an alarm that gets me to run to the laser than just let it burn to the ground because I didn't know there was a problem.


Heh, ok.


It be nice if it shut down the machine, air assist, and blower.
Then flooded the main chamber with nitrogen gas.


Steve or Dan,

Do you know the temp rating of the sensor by chance?

Brian Fiore
10-24-2010, 1:57 PM
:confused: What CO? How much material do you think your laser is burning?

:D

I don't know how much CO is produced, but I thought CO is heavy stuff relaitive to the rest of the components in the air and can accumulate over time?

Probably overkill, but with little ones around don't want to take any chances.

Scott Shepherd
10-24-2010, 3:24 PM
I can't find any info on that thermal sensor, but I seem to recall seeing it one time. Maybe in the 130-150 degree range if I remember correctly.

I'm pretty sure it shuts the machine down. The machine will not run without the battery installed for it.

Mike Lassiter
10-24-2010, 5:08 PM
copied from the ULS manual:

ALARMS alerts you if the inside of the laser system is above the recommended temperature or if the Thermal Sensor battery is low in power. If the Thermal Sensor inside the laser system is triggered, an alarm will sound and shut down your laser system.

This was listed for each type of machine (VLS,PLS & ILS).

Robert Walters
10-24-2010, 5:21 PM
I can't find any info on that thermal sensor, but I seem to recall seeing it one time. Maybe in the 130-150 degree range if I remember correctly.

I'm pretty sure it shuts the machine down. The machine will not run without the battery installed for it.

Battery?! Does it have vent holes by chance?

I don't think I've ever seen a temp sensor use a battery.

I was expecting it to be something like an attic temp sensor with a metal disc at the center. But those are usually at 160F and higher for fire alarms.

Scott Shepherd
10-24-2010, 5:30 PM
I don't know what it is, I just know there's a 9V battery that is installed in the side of the machine, near the back, with a test button on it, and then there's a little rectangle box inside the cabinet, just above the plenum.

I've changed the battery on it, but that's about all I know.

Shawn Cavaretta
10-25-2010, 7:18 PM
:confused: What CO? How much material do you think your laser is burning?


i have a CO detector in my room where my laser is and have set it off once. in my shop wher ei had it i was using a home built air scrubber venting back in to the room and thats when it went off.

i have moved the machine from that location and i am not venting back outside and have not had any problem but keep the CO detector next to the machine

Robert Walters
10-25-2010, 8:23 PM
copied from the ULS manual:

ALARMS alerts you if the inside of the laser system is above the recommended temperature or if the Thermal Sensor battery is low in power. If the Thermal Sensor inside the laser system is triggered, an alarm will sound and shut down your laser system.

This was listed for each type of machine (VLS,PLS & ILS).


Thanks Mike,

Good to know. Though I think I'd poo my pants if the temp alarm went off just for a low/dead battery :eek:



If anyone is so inclined to take a photo of this temp sensor, I'd appreciate it!

Scott Shepherd
10-25-2010, 8:26 PM
The alarm doesn't go off for a dead battery, if I recall correctly. I think it chirps like the one in your home, if it's battery operated.

I think it got me one year. Took me a while to track down the chirp that happened every so often. You'd hear it, get up to find it, it wouldn't chirp again. You'd go to doing something else and it would chirp again :)

Dan Hintz
10-25-2010, 9:29 PM
i have a CO detector in my room where my laser is and have set it off once. in my shop wher ei had it i was using a home built air scrubber venting back in to the room and thats when it went off.

i have moved the machine from that location and i am not venting back outside and have not had any problem but keep the CO detector next to the machine
I'm assuming it has activated carbon in it? Get activated carbon wet (including moisture from the air) and it sucks local oxygen right up. not much of a concern unless you're in a sealed room, but it could be enough of a dip to set off a CO detector.

Was it an electrochemical, metal oxide, or biomimetic detector?

Robert Walters
10-25-2010, 10:11 PM
I think it got me one year. Took me a while to track down the chirp that happened every so often. You'd hear it, get up to find it, it wouldn't chirp again. You'd go to doing something else and it would chirp again :)

Dont ya hate when that happens!

Wil Lambert
10-26-2010, 1:49 PM
I have though about adding one in for fire suppression. I don't think it would be that hard to rig up a detector attached to a solenoid and a CO2 tank. At work we have suppression systems on the EDM machines. Basic system. Detects flame and opens a solenoid up for the tanks.

It would be worth the cost and effort if it saved the machine once.

Lee DeRaud
10-26-2010, 2:04 PM
I'm assuming it has activated carbon in it? Get activated carbon wet (including moisture from the air) and it sucks local oxygen right up. not much of a concern unless you're in a sealed room, but it could be enough of a dip to set off a CO detector.

Was it an electrochemical, metal oxide, or biomimetic detector?If a CO detector thinks it detected CO and just chirped and reset itself without human intervention, it's dangerously defective, IMHO.

Dan Hintz
10-26-2010, 2:41 PM
Lee,

That's why I asked about the type... the biomimetic detectors use a gel that mimics the hemoglobin in our blood and turns dark when exposed to CO (getting darker with longer/stronger exposure), but I do not know off-hand if the gel reverts back in color by releasing CO back into the atmosphere. The metal oxide semiconductor and electrochemical versions typically only work while the concentration is above a certain amount... once the air clears, they may no longer scream, but the manufacturer may build in a delay so they at least scream for a period of time afterwards.

EDIT: Hmmm, I also just found out the biomimetic versions can also be tripped by temperature extremes and high humidity... that's a new one for me.

Robert Walters
10-26-2010, 4:58 PM
EDIT: Hmmm, I also just found out the biomimetic versions can also be tripped by temperature extremes and high humidity... that's a new one for me.

<sarcasim>That's just lovely,</sarcasim>
Especially now when CO alarms are required under code.

Thanks Dan, I'll be sure to read the box more carefully to see what method they use.

Dan Hintz
10-27-2010, 9:50 AM
Better than the electrochemical ones, Robert... you have to replace those every couple of years as the sensors slowly wear out.

Joshua Hopper
10-29-2010, 12:41 PM
Seeing that cheap epilog 36 (http://www.sawmillcreek.org/showthread.php?t=125121) has got me really thinking about buying a dedicated detector....

who else has??? :confused:


I simply glued a home version of a smoke detector into the inner side of the removable door on my Epilog Legend 32 / The Big Boy. The smoke when cutting normaly doesn't bother it, but I went to the restroom for about 2 mins about a year ago after instaling it and the X-Axis belt broke, the head stopped moving and the beam sat in one spot and caught the acrylic on fire. The amount of smoke from that, even my blower motor couldn't handle it all and it set the alarm off. A few more minutes and my whole machine could have been done for. As it is I only had to replace 1 or 2 small parts and a new lens instead of a new machine.

My opinion, get something. It doesn't have to be perfect but chances are it will atleast give you more notice that nothing.

Good Luck

Tom Delaney
10-29-2010, 3:35 PM
This thread raises a very interesting point I'd never considered, that being CO. A few points to consider - CO is not heavier than oxygen but rather replaces it. Secondly, it 'accumulates' on the red blood cells in the body and (if I recall) is is 10x more difficult to remove from the RBC than the oxygen molecule. In other words, if there is a slight accumulation over time, it can mess you up and the threshold to cause harm is extremely low. I don't have a CO detector in the engraving room, but I do have 3 in my home and am now going to have a fourth! Cheap insurance against a potentially dangerous situation - especially for those who are engraving continually. It is one of those things that can grow on you...