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Bert Kemp
01-06-2016, 1:56 PM
I have no amp meter on my machine and have never really worried about it because my machine was setup by Ray and I have never run it at over 70% PWR since I've owned it. Ihave a hand held multi meter could I check my machine with this and how would I do it.:confused:

Ross Moshinsky
01-06-2016, 2:22 PM
You paid a premium to buy a Rabbit laser so that you could call up them up and ask this type of question.

David Somers
01-06-2016, 2:34 PM
Good morning Bert!

Here is a link to a thread that discusses the installation of a meter.
http://www.sawmillcreek.org/showthread.php?237268-Installing-a-mA-meter&highlight=amp+meter
and a second useful post with a bit more discussion
http://www.sawmillcreek.org/showthread.php?176291-Milliammeter-for-laser&highlight=ammeter
I know there is another where someone photographed the installation at the tube but I couldnt find that in the few minutes I had available.
Hope these help Bert!

Personally, I think I would do a solid install so I am not fussing with loose connections and trying to manage the meter and its contacts to the wire while actually operating the machine. There are some other threads that discuss this issue as well. IF you are going to take the time to use one of these, the added time of installing one permanently is reallllly minor.

If the descriptions in the threads are not enough you might give Ray a buzz. He can guide you to the right connection without hesitation.

Dave

Bill George
01-06-2016, 3:00 PM
Basically you put a mA meter in the Negative lead of the tube. This is high voltage, so make darn sure the power is off and I would unplug the power plug. LightObject sells a pretty decent meter and you want it to have a scale 2x the normal reading of your tube, in mA DC. If you expect to see 50 then a 0-100 mA, if you expect to see 25 then a 0-50.

Bert Kemp
01-06-2016, 3:08 PM
I don't want to install a permanent meter I was just thinking a quick check hooking up a temp multi meter with clips of something.



Basically you put a mA meter in the Negative lead of the tube. This is high voltage, so make darn sure the power is off and I would unplug the power plug. LightObject sells a pretty decent meter and you want it to have a scale 2x the normal reading of your tube, in mA DC. If you expect to see 50 then a 0-100 mA, if you expect to see 25 then a 0-50.

Bert Kemp
01-06-2016, 3:10 PM
Ross why should I bother Rabbit when I contribute :Dhere to get questions answered I notice you do not



You paid a premium to buy a Rabbit laser so that you could call up them up and ask this type of question.

Bill George
01-06-2016, 3:26 PM
I don't want to install a permanent meter I was just thinking a quick check hooking up a temp multi meter with clips of something.

I don't know what meter you have and what ranges the DC mA it will display. The leads go in Series with the negative lead of the tube. Get it wrong and its good by meter.

Bert Kemp
01-06-2016, 3:30 PM
Thanks Bill to complicated for me I won't bother. Thought it would be easy like connect red here black here.



I don't know what meter you have and what ranges the DC mA it will display. The leads go in Series with the negative lead of the tube. Get it wrong and its good by meter.

Chris Corwin
01-06-2016, 5:42 PM
It is easy. Takes 5 min.

Cut the skinny wire from the tube and wire the two new ends to the two screws on the meter.

End of story.

Jerome Stanek
01-06-2016, 5:54 PM
Thanks Bill to complicated for me I won't bother. Thought it would be easy like connect red here black here.

It is pretty easy the black smaller wire near you lens end of your laser comes off and attaches to one side of your meter and the other lead attaches to the post of the meter.

Bert Kemp
01-06-2016, 6:02 PM
I guess are meters are different mine has to leads that come off it red and black. So I'm guessing I hook the red to one side and the black to the other. OK maybe just buy a meter
is this one right http://www.lightobject.com/-DC-30mA-Analog-Panel-Meter-44C2-P934.aspx



It is pretty easy the black smaller wire near you lens end of your laser comes off and attaches to one side of your meter and the other lead attaches to the post of the meter.

Bert Kemp
01-06-2016, 6:08 PM
What would I expect to see with my 60 watt tube.:confused:


Basically you put a mA meter in the Negative lead of the tube. This is high voltage, so make darn sure the power is off and I would unplug the power plug. LightObject sells a pretty decent meter and you want it to have a scale 2x the normal reading of your tube, in mA DC. If you expect to see 50 then a 0-100 mA, if you expect to see 25 then a 0-50.

Scott Shepherd
01-06-2016, 6:12 PM
Make sure you don't cut the blue wire. That one always caused problems for people in the movies.... just saying... :D

Bill George
01-06-2016, 6:29 PM
What would I expect to see with my 60 watt tube.:confused:

I'd get this one its rated at 50 mA, and its cheap enough. Then you just need some black insulated stranded wire and some splices and terminal ends. http://www.lightobject.com/DC-50mA-Analog-Panel-Meter-44C2-P935.aspx

The hard part is going to be mounting it.

David Somers
01-06-2016, 6:46 PM
Bert, If you go to Radio Shack or whatever its equivalent is now, you will find some small black project boxes you can use to mount the meter. Then all you need is a small hole in the laser cabinet to pass the wires through, and a few screw holes to mount the box, or even just double sided tape if you want.

Dave

Bert Kemp
01-06-2016, 7:12 PM
I have a cover plate right on the machine,by the end of the tube, I think theres enough room to cut a hole in that plate and just mount the meter in it. If not I'll do as you suggested.:)Thanks Dave


Bert, If you go to Radio Shack or whatever its equivalent is now, you will find some small black project boxes you can use to mount the meter. Then all you need is a small hole in the laser cabinet to pass the wires through, and a few screw holes to mount the box, or even just double sided tape if you want.

Dave

Bert Kemp
01-06-2016, 7:14 PM
Thanks Bill I just ordered one, its going to come close to bankrupting me:Dbut what the hell huh.Oh see my reply to Dave on mounting.





I'd get this one its rated at 50 mA, and its cheap enough. Then you just need some black insulated stranded wire and some splices and terminal ends. http://www.lightobject.com/DC-50mA-Analog-Panel-Meter-44C2-P935.aspx

The hard part is going to be mounting it.

Kev Williams
01-06-2016, 7:40 PM
Since you have to disconnect or cut the wire to test the amps, you might as well install a permanent meter.

I'm glad I have mine, I've learned a few things from it. Like when vectoring, and I'm sure I'm not alone, I have to choose 2 power levels, one for fast or long runs and a lower level for when the machine slows down for sharp corners or tight curves. Watching the needle dip is fun, and sometimes it doesn't when I think it should, and vice versa... and other times I've noticed it running at the lower power level when I thought it would be running the higher power. I'm still learning how it all correlates. You get to know how much actual power it's taking to cut thru certain materials and thicknesses, learn what power% entries = the mA... A meter is a good thing!

Glen Monaghan
01-06-2016, 8:13 PM
If you only expect to check the current once, then using the multimeter is a little easier. However, if you ever expect to do it again, just go ahead and install a panel meter permanently. A permanent connection is considerably less bother than repeatedly powering down the laser, opening up the cabinet, disconnecting the (black) ground wire from the tube, clipping in the multimeter using the correct jacks and ampere scale with the red meter lead to the now disconnected tube lead and the black meter lead to the lug where the tube lead was originally connected, making sure the meter is securely situated so it won't fall or get knocked down and you can still read it when the laser is on, powering up the laser, setting up/starting a job, getting a current reading, shutting down the laser, removing the multimeter, reconnecting the tube's wire, and buttoning up the cabinet, all that each time you want to check the current...

Bert Kemp
01-06-2016, 8:25 PM
Yep I'm putting one in its ordered:)



If you only expect to check the current once, then using the multimeter is a little easier. However, if you ever expect to do it again, just go ahead and install a panel meter permanently. A permanent connection is considerably less bother than repeatedly powering down the laser, opening up the cabinet, disconnecting the (black) ground wire from the tube, clipping in the multimeter using the correct jacks and ampere scale with the red meter lead to the now disconnected tube lead and the black meter lead to the lug where the tube lead was originally connected, making sure the meter is securely situated so it won't fall or get knocked down and you can still read it when the laser is on, powering up the laser, setting up/starting a job, getting a current reading, shutting down the laser, removing the multimeter, reconnecting the tube's wire, and buttoning up the cabinet, all that each time you want to check the current...

Jerome Stanek
01-07-2016, 7:33 AM
I mounted mine just above my key pad. I think I had to drill a 2 inch hole and 2 small holes for the mounting studs looks like it came on the machine

Bill George
01-07-2016, 9:51 AM
I mounted mine just above my key pad. I think I had to drill a 2 inch hole and 2 small holes for the mounting studs looks like it came on the machine

For that he would need a 2 inch hole saw and those aren't cheap especially for a one time use. Not counting the metal shavings inside the machine IF your not real careful. I think the plastic enclosure box or a plastic electrical box 4x4 with a blank cover would be easiest. He can cut those holes with his laser. Small hole in the machine for those two wires and he is done.

Bert Kemp
01-07-2016, 10:48 AM
Just so I don't misunderstand any thing this is what I'm going to cut and hook to meter, after I power down laser and unplug for 10 min's. Correct?328836

Jerome Stanek
01-07-2016, 11:17 AM
For that he would need a 2 inch hole saw and those aren't cheap especially for a one time use. Not counting the metal shavings inside the machine IF your not real careful. I think the plastic enclosure box or a plastic electrical box 4x4 with a blank cover would be easiest. He can cut those holes with his laser. Small hole in the machine for those two wires and he is done.

No metal shavings if you use a magnet next to the bit shavings stick to that

Jerome Stanek
01-07-2016, 11:20 AM
Just so I don't misunderstand any thing this is what I'm going to cut and hook to meter, after I power down laser and unplug for 10 min's. Correct?328836

That is correct. On mine I could take the wire off the tube to test with my multimeter. I like that I can keep an eye on the power and see if it always is the same. I had one file that I wanted to cut at 70% but the meter was showing it was only cutting at 30%. I had to adjust some other settings to get what I wanted.

Jeff Body
01-07-2016, 1:07 PM
Just so I don't misunderstand any thing this is what I'm going to cut and hook to meter, after I power down laser and unplug for 10 min's. Correct?328836

Or you can follow that wire to the power supply and disconnect it from there. (normally just a hold down screw) Then extend that wire to your meter and than run another wire from your meter back to the point where you disconnected it from the power supply.
It's a whole lot easier then cutting the wire at the tube.