Bought new PWM but it still wont fire

lcornwell36
Posts: 11
Joined: Tue Apr 22, 2014 9:41 am

Bought new PWM but it still wont fire

Postby lcornwell36 » Wed Apr 12, 2017 12:37 pm

I have been trying to figure out what is wrong after my fuse blew. When the fuse blew heard a loud pop. Replaced the fuse and no fire. Looked at the laser power supply and fuse had blown. Replace the fuse in the laser power supply and still no fire and the fan wasn't working so I just replaced my laser power supply thinking that was the problem. I have a new tube on the way but I really don't think it is the tube. I have tried everything except testing the laser power supply to see if it is firing. I have looked for a more elaborate way to test the power supply. I did see the post where Macro explains how by using a wire against the case however Im not 100% sure by his written explanation.

New 45w laser power supply. Could it be that I received a bad laser power supply. This is the new model and doesn't have the fire button. The fan does come on.

45w laser tube. I have done an inspection of my tube which was bought in Dec 2016 and cant find any cracks. Everything looks right on the tube.

I have the dsp conversion with the awc608 controller

Any help would be greatly appreciated!

Tech_Marco
Posts: 4323
Joined: Mon Jun 15, 2009 3:00 pm

Re: Bought new PWM but it still wont fire

Postby Tech_Marco » Wed Apr 12, 2017 12:56 pm

You may had a lose connection non the tube while trying to power it up and caused opened circuit. When firing a laser tube with opened circuit, the charge from the power supply will cause a spark and he power supply may be blew.

You need to check the wire connection and make sure that is is firmly connected. It is very easy to ignore the loose connection on a current meter and lead to fuse blew or power supply blew.

We tested all our power supply and laser tube before shipped. If you heard a pop sound from the firing, the chance was that you may have an opened circuit and that caused the spark. Most likely the LPSU is damaged (75% chance)

When we tested a new power supply or new tube, we always set it low current. With Lowe current output and opened circuit, the LPSU survived in most case because of opened circuit


Marco

lcornwell36
Posts: 11
Joined: Tue Apr 22, 2014 9:41 am

Re: Bought new PWM but it still wont fire

Postby lcornwell36 » Wed Apr 12, 2017 1:24 pm

Tech_Marco

The loud pop was on the old power supply. New LPSU was installed today but laser still not firing. I have a new tube on the from you. Connections were solid no open circuit on new LPSU. Is there anything else I could check.

Tech_Marco
Posts: 4323
Joined: Mon Jun 15, 2009 3:00 pm

Re: Bought new PWM but it still wont fire

Postby Tech_Marco » Wed Apr 12, 2017 1:58 pm

Make sure the WP is grounded

Marco

lcornwell36
Posts: 11
Joined: Tue Apr 22, 2014 9:41 am

Re: Bought new PWM but it still wont fire

Postby lcornwell36 » Wed Apr 12, 2017 2:04 pm

Tech_Marco wrote:Make sure the WP is grounded

Marco


Did that too. I even disconnected and put a jumper in to make sure.

Tech_Marco
Posts: 4323
Joined: Mon Jun 15, 2009 3:00 pm

Re: Bought new PWM but it still wont fire

Postby Tech_Marco » Wed Apr 12, 2017 2:25 pm

Then try it without the controller:

Only on the LPSU terminals:
1) Ground WP
2)Connect 5V to the input
3) Touch TL to ground will get you more than full power output
So just hold that in 1 seconds or less


Marco

lcornwell36
Posts: 11
Joined: Tue Apr 22, 2014 9:41 am

Re: Bought new PWM but it still wont fire

Postby lcornwell36 » Mon Apr 17, 2017 2:49 pm

Lpsu fires manually. Could it be that my previous lpsu was the old style? I read where you posted the new 45watt lpsu wiring manuel which states that the wp doesnt need to be connected to geound if it is turned on in the dsp. Would having dsp cut off and grounding the wp cause it not to fire?

Is there a way to check and see if the dsp is bad?

Thanks!

lcornwell36
Posts: 11
Joined: Tue Apr 22, 2014 9:41 am

Re: Bought new PWM but it still wont fire

Postby lcornwell36 » Tue Apr 18, 2017 6:29 am

Laser is working now. My settings on the fire button on the dsp control panel was set to 5% which was fine on the previous 45watt power supply. I didn't think to change the setting since it worked with the old one. I now have to run DSP controller at 11% to get any sign of laser fire.

Techgraphix
Posts: 457
Joined: Fri Jan 20, 2012 1:39 pm
Location: Appelscha, the Netherlands
Contact:

Re: Bought new PWM but it still wont fire

Postby Techgraphix » Wed Apr 19, 2017 5:15 am

It's quite normal that a lasertube has an offsett of around 12%..
Maybe you like this article:
http://www.lightobject.info/viewtopic.php?f=8&t=2522&hilit=scaling#p12236

Kees


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