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Steve Conner

Thu Aug 13 2009, 01:58PM

Registered Member #30 Joined: Fri Feb 03 2006, 10:52AM
Location: Glasgow, Scotland
Posts: 6706

Well we can't help you without more details. How about posting a schematic of the power supply?

Jonathan Dennis

Thu Aug 13 2009, 02:34PM

Registered Member #2153 Joined: Wed Jun 03 2009, 03:19PM
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Posts: 69

Here is a schematic of the power supply, hope it helps.

Steve Conner

Thu Aug 13 2009, 03:06PM

Registered Member #30 Joined: Fri Feb 03 2006, 10:52AM
Location: Glasgow, Scotland
Posts: 6706

Hmm, so looking at that, I'd guess you could replace C1 with a bigger capacitor (or add a bunch in parallel with it) and connect 240V to two of the three line inputs.

You'll need to check the variable transformer settings (they probably want to go up pretty high, 240 is near the top of the range) and also make sure it doesn't overheat, since two sets of windings will be carrying a level of power meant to be shared between three. You may also need to check that you're using the *right* two inputs, since I notice that two of the transformer's three coils have taps for powering control circuits and so on.

But I'd wait for a second opinion from the laser gurus before doing anything.

*Edit* Oh, I realised I just typed out more or less what the laser forum guy said. So naturally I agree with it :P

Jonathan Dennis

Thu Aug 13 2009, 03:14PM

Registered Member #2153 Joined: Wed Jun 03 2009, 03:19PM
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Posts: 69

That all sounds good except 1, I don't have any more capacitors, used them all for my tesla. 2, I don't have two 240V sources. All I have is one dryer outlet, and I don't want to wire to the main because I don't feel comfortable with my skills to do so.

Steve Conner

Thu Aug 13 2009, 03:20PM

Registered Member #30 Joined: Fri Feb 03 2006, 10:52AM
Location: Glasgow, Scotland
Posts: 6706

Dude, it'll plug into the 240V dryer outlet fine. The outlet has two live prongs and a ground. I'm suggesting you connect them (edit: the two lives) to two of pins 1,2,3 on TB1 (I'm not telling you which two, you have to figure it out yourself) and the ground to pin 5 on TB1.

You can pick up a big 350V electrolytic capacitor for $10-20, just ask in the sale and trade forum. Single phase power needs more smoothing than three phase, so I expect C1 might overheat and blow out if it wasn't reinforced by another cap or two.

You do know not to stare into the laser beam when it's on, right?

Jonathan Dennis

Thu Aug 13 2009, 03:44PM

Registered Member #2153 Joined: Wed Jun 03 2009, 03:19PM
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Posts: 69

that sounds like something I can manage! It looks like it needs to connect to pins 1 and 3. Also, if I wanted to get the 240V anywhere in my house, could I use a variac?
*update*, They are hosting SELEM in South Carolina this weekend, it will be a ton of laser experts running around. Several told me if I bring it, they can help me fix it to run on single phase power so I can hook it up in my house!

...

Thu Aug 13 2009, 04:07PM

Registered Member #56 Joined: Thu Feb 09 2006, 05:02AM
Location: Southern Califorina, USA
Posts: 2445

Another thing to consider would be getting a VFD (variable frequency drive) off ebay. They are basically a phase converter, but are designed to run motors so you can change the output frequency/voltage at will. Usually they are designed for 3 phase input, but many are rated to have a single phase (they have the extra filtering capacitance that Steve mentioned), and larger rectifiers on one of the phases. Then powering the laser would just be a matter of setting it for a 60hz output and not blowing any fuses, but they aren't exactly cheep even used.

Cheers

GeordieBoy

Thu Aug 13 2009, 04:30PM

Registered Member #1232 Joined: Wed Jan 16 2008, 10:53PM
Location: Doon tha Toon!
Posts: 881

> Another thing to consider would be getting a VFD (variable frequency drive) off ebay...

By VFD do you mean a solid-state drive inverter? or a variable speed DC machine connected to a 3-phase AC generator?

If you meant the power electronics variety, then that assumes that the VFD will be compatible with driving the laser power supply. Often inverters don't tolerate capacitive loads too well. The VFD will most likely be designed with a motor or other net inductive load in mind, so i'm not sure how well it might tolerate a capacitive load such as a 3-phase bridge rectifier!

-Richie,

Jonathan Dennis

Sun Aug 16 2009, 05:48PM

Registered Member #2153 Joined: Wed Jun 03 2009, 03:19PM
Location:
Posts: 69

All right! I went to the south east laser enthusiast meeting in NC, and found out that this is apparently the holy grail of all lasers. It's a Super nice system with all the bells and whistles and it was putting out 2W of laser light after we cleaned the optics and tuned it. The red wasn't "low" it was just out of alignment which was quickly fixed. It's a beautiful system and I found out from the Ion laser guru that there is a converter I can get to run it on single phase no problem. I was also encouraged to get into the laser show buisness. So if anyone knows of any corporate parties or anything that might need laser light to liven it up, let me know. I should be up and running soon. I simply need to resubmit all the paperwork and take care of the legal paper work. It's a beautiful laser... really. I'll post some pics soon.

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