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Sandy Henry
07-26-2010, 12:19 AM
I have a Synrad Power Wizard 250 meter for checking laser wattage output. It has never been used. Purchased CHEAP at bank auction (business foreclosure) A very brief, 2 sentense instruction on back... "place black target in beam untill meter beeps". Doe's anyone know how to get my Epilog Legend 36 to fire laser beam while not moving in x or y ? I'd love to check my wattage. Thanks! Sandy

John Noell
07-26-2010, 1:26 AM
Not the right answer, but could you (very slowly) vector a small enough circle to stay within the target area?

Dan Hintz
07-26-2010, 6:55 AM
John,

A workable solution, as long as Sandy (and you) realizes the measurement is to be taken at the output of the tube, not at the table (i.e., before it is focused).



Sandy,

I have the same meter... the instruction manual is available online from Synrad. Get it and read it, the two-line instruction is more of a reminder rather than full instructions as there are some caveats to be aware of.

Michael Hunter
07-26-2010, 6:58 AM
I've not tried this, but it might work -
Go to the maintenance menu of the control panel on the machine and set "Disable Axis".
(The power is now removed from the motors and the carriage can be moved by hand so that it is over the meter)
Now try running a job.

Rob Patterson
07-26-2010, 7:33 AM
Doe's anyone know how to get my Epilog Legend 36 to fire laser beam while not moving in x or y ? I'd love to check my wattage. Thanks! Sandy

You can fire the laser by pressing the up arrow while in the "align laser" option under the maintenance mode menu on the machine itself.

Warning: the laser will fire with the cabinet door open (and your hands in the path) while in this mode. Be very careful!!!

Carl Sewell
07-26-2010, 9:29 AM
Make sure that the laser is way OUT OF FOCUS when you are measuring the power. Otherwise, you may cook the meter.

I use a spiral that is a smaller diameter than the meter sensor. That gives me time to close the laser door and still get a good reading. Adjust the spiral or laser speed to make sure that the laser is operating for about as long as the sensor is taking readings. You should see the meter start to stabilize before the laser quits firing.

Position the meter. Hold the button on the meter down. Start the laser program. Release the meter button and close the laser door.

Sandy Henry
07-26-2010, 10:01 AM
Thanks to all for your advise. I will get the detailed instructions from Synrad...then I'll try it or maybe think better of it & just sell the meter! I know its an expesive little gadget & it would be a shame if I ruined it. Thanks again! Sandy

Richard Rumancik
07-26-2010, 12:51 PM
I would suggest you don't sell it - unless it is to me . . .

Here is the operating info on the instrument as a pdf:

http://www.synrad.com/Products/powerwizard.htm

Just be careful and you will be fine. You want to be out-of-focus so it doesn't damage the sensing face.

Most lasers have a maintenance routine for doing beam alignments - you can set the power to x% then press/hold a button to fire the laser for a number of seconds.

You may have to modify the Synrad steps a bit. eg For table measurements don't hold the instrument in your hand.

Mark Winlund
07-26-2010, 1:32 PM
ULS used a meter with what looked like a stone with a thermometer attached. Run the laser for a predetermined time, measur the temp. increase, consult a chart to get power.

Mark

Martin Boekers
07-26-2010, 1:44 PM
When a sales rep checked mine awhile back (not sure which device he used) He took off the side panel and measured the beam before it reached the I-Beam mirror.

We fired the laser from the maintainence menu.

Marty

greg lindsey
07-26-2010, 6:38 PM
According to Epilog, the synrad power meter reads differently than the actual output of Epilogs laser tubes, the meter will read a lower power than the tube is actually puting out, it is a precentage, can't remember what that precent acually is, calling EL tech support will help. I did this recently when I wanted to ck the output of my machines, I rented the meter from laserbits, 100.00 for 1 week. I called EL tech support and was told that best way to measure was to put the machine is dead perfect alighnment, to do this was to use thier XY axis disabler, free to use but a 175.00 deposit required. This allows you to have full funcion of the machine without the motors turning. Pull the crossarm forward and unplug the white ribbon cable and plug in the disabler, it even has toggle switch on it to fire the laser, very safe and easy to use.

Sandy Henry
07-26-2010, 11:06 PM
Must thank everyone again for your input. This forum is fantastic!
I'm currently overwhelmed with work but will try this "Wizard" asap.
I'll let ya-all know if I succeed. Thanks again! Sandy

Richard Rumancik
07-28-2010, 12:13 AM
According to Epilog, the synrad power meter reads differently than the actual output of Epilogs laser tubes, the meter will read a lower power than the tube is actually puting out . . .

Well, I'd like to hear the explanation from Epilog as to why they feel that the Synrad instrument is inaccurate. (Maybe Synrad would also be interested.) I think Synrad has packed a lot of technology (heat transfer theory, thermodynamics and physics) into a pretty compact instrument; I have a feeling that they did their homework. Basically it works on the principal that by knowing the initial temperature of the aluminum sensing mass, and controlling the duration that the laser beam impinges on the sensing mass, the laser power can be indirectly determined by measuring the final temperature. The instrument takes into account transient cooling and doesn't have to be cooled down before the next use (you can use it several times in succession.)

For the record, GCC lent me a PowerWizard many years ago and they did not say it was inaccurate or needed a fudge factor. What does Trotec, ULS, and the rest say? Is there anyone from Epilog that can clarify the comment? Perhaps it is not the official Epilog position.

Dan Hintz
07-28-2010, 7:34 AM
Richard,

This issue with Epilog machines and the Power Wizard have been brought up before, and my mind immediately started asking the same questions as you (I can't remember if I said so publicly, but I think I did). It made no sense for the exact reason you mentioned... the PW takes an average reading of power due to heating up a known mass over a long period of time (several seconds), so pulse width or duty cycle is irrelevant.

Mark Winlund
07-28-2010, 8:00 AM
Well, I'd like to hear the explanation from Epilog as to why they feel that the Synrad instrument is inaccurate. (Maybe Synrad would also be interested.)

Well, most likely the explanation is that lasers are generally sold by the watt... more watts = higher price. It's sort of like "sears horsepower" when selling air compressors. You wind up seeing a 7 1/2 hp air compressor that draws 10 amps on a 120 VAC circuit. For a while, they called it "peak horsepower", that is, that instantaneous moment of power measured at the point where the motor self destructed! Think vacuum cleaners.

Mark

Kim Vellore
07-28-2010, 11:27 AM
I guess Epilog used to do that before. My machine is a Epilog 45TT (45 watt machine) but the tube inside is a 40W tube, When I asked them about it they told me they measure the output and that's how they classify the machines... I thought that was not right. I am sure there is some consumer protection law against that. I dont think they are still doing that now.

Kim

Dan Hintz
07-28-2010, 11:56 AM
Kim,

All tubes have a small window of power range due to the construction methods and materials used (one surface isn't perfectly mirrored at the correct angle, the next batch of gas is slightly off, etc.). That's the reason why two tubes designed in exactly the same manner can be 10-20% different in power levels. If Epilog chooses to use a nominal 40W cartridge that measure 45W and call it a 45W machine, that's their prerogative. I don't know about any manufacturer other than ULS, but I do know ULS accepts anything within +/- 10% of the rated value to be acceptable... they also choose to downrate their tubes in almost every case so no one can come back and say they were ripped off. My 60W cartridge lases at 70W+...

greg lindsey
07-28-2010, 5:18 PM
Whether or not this is Epilog position, is up to them, I mearly stated what I was told by EL support. I am not trying to throw any EL techs under the bus, they are the best in the business, but just passing along what I was told. When I tested my summits on the synrad power meter they tested at 6 watts on a 25 watt machine, yes I know they are dinosaurs, but they work fantastic and there is no way they are only putting out 6 watts. I have had these machines in production for 10 yrs and both still produce the same way as the day I got them.