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Walt Langhans
06-07-2014, 2:47 PM
Hey guys!

So my power supply bit the dust and I just got the new one in, and I wanted to double check how I 'think' the new unit should be wired, against someone who hopefully "knows" how is supposed to go. I know just about enough to get me into trouble so I'd like to avoid killing the new power unit with my own incompetence :D

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Above is the old power supply still wired in. On the left it say FG AC AC. On the right it says 5v TH TL WP G IN

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Above is the new power supply.

1/ Since everything on the left is the same I assume I can just swap the wires in the order that they are?

2/ I assume that the H L P on the new supply are the same as TH TL WP respectively?

3/ And then it's just a matter of moving the old wires over to the corresponding spot of the new power supply?

Thanks!

Robert Walters
06-07-2014, 3:21 PM
Did you get a manual for the new PS?

Where did you purchase it from (provide link if possible)?

Walt Langhans
06-07-2014, 3:33 PM
No manual, I got it from lightobjects

Robert Walters
06-07-2014, 3:51 PM
I could not find your EXACT power supply on their website (which is why I asked for a link).

This is the closest I found for a "manual", there is also a PDF that you can downoad near the bottom of the page that gives some pinouts at least. Not sure if they are for *YOUR* ps or not, you've been warned =)


http://www.lightobject.info/viewtopic.php?f=16&t=18


Heh, it's funny your new PS has what looks like a date code of "201406052"...
2014-JUN-05 #2 Maybe? lol

Did you pick it up in person or had it overnighted to you?
Cause that's only 2 days ago (today being 2014-JUN-07)

Scott Shepherd
06-07-2014, 8:36 PM
Robert, I think they list the day/month opposite of the USA. So that could easily be May 6,2014.

Allen Rawley
06-07-2014, 8:48 PM
Hi Robert,

Your logic is correct. You can wire the controls per your listing. We have wired many different power supplies for our customers and get this question regularly.

Robert Walters
06-07-2014, 9:43 PM
Robert, I think they list the day/month opposite of the USA. So that could easily be May 6,2014.



You could be right, usually YYYY-MM-DD (HH:MM:SS) is the unambiguous format (TIMESTAMP14).
But eh, no biggy either way =)

Robert Walters
06-07-2014, 9:46 PM
Your logic is correct. You can wire the controls per your listing.


I'm just surprised they didn't at least include a single sheet instruction page.

Once I saw the signal names, I thought I'd at least give the link.

Walt Langhans
06-08-2014, 6:06 PM
Hi Robert,

Your logic is correct. You can wire the controls per your listing. We have wired many different power supplies for our customers and get this question regularly.

Thanks Allen :D

Bruce Dorworth
06-09-2014, 2:53 AM
Walt, the way I see it the connections on the new power supply are not the same as your old one. Look at the key on the silver label. Notice the letters H L P G IN 5V, Instead of 5v being your first connection it is last on your new supply, the other connections H/TH, L/TL, P/WP, G and in are the same order. I am far from an expert, but that is the way I see it. The AC seems to be exactly like the old one.

Bruce

Keith Colson
06-09-2014, 4:47 AM
If it was me I would label each wire as I removed it and then place each labeled wire back into the desired slot. As Bruce said the connections are clearly in a different order but the pins can be matched up.

The other thing I would do is fix all that contamination that is getting into the power supply. This is probably the cause of failure. Your board should not get dirty at all. How is all that contamination getting onto the power supply and circuit board?

Cheers
Keith

Walt Langhans
06-09-2014, 12:46 PM
Well the new power supply is in.

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And it ran fine for about 10 minutes, then the fuse at the AC power plug blew. I don't happen to have the fuse (f5al250v) that I need on hand so I need to go and get another one, however I am a bit concerned that the new power supply blew the fuse. Anyone have any thoughts / ideas of what might be up? Granted I realize it could be the fuse and won't find out till I put in a new one, but my gut's telling me there might be another issue.

Kev Williams
06-09-2014, 1:14 PM
Must concur with Bruce & Keith on the right-side connector. The difference between the 2 is the 5v spot is on the far left on the old supply, it's on the far right on the new supply. Otherwise identical. Left-to-right connections are identical in sequence, but you use the MIDDLE four spaces on the new supply vs the RIGHT four spaces on the old, leaving the far left and far right spaces open...

Dave Sheldrake
06-09-2014, 1:53 PM
POT control or DSP Walt?

cheers

Dave

Walt Langhans
06-09-2014, 4:14 PM
I replaced the fuse and hit the pulse button and the laser fired.

However, the amp meter on the hit 40, I'm usually in the 20 - 25 range. Anyone have a clue on what might be going on and how to fix it?

Walt Langhans
06-09-2014, 6:30 PM
Also I've noticed the LED on the power supply is trying to tell me something but I don't know what it is.

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Glen Monaghan
06-09-2014, 7:39 PM
According to the legend below the warning triangle, the L means no laser signal.

Keith Colson
06-09-2014, 7:48 PM
L says no laser signal and 0 is no milliamps, Maye because it is off. I found a manual, not an exact mach but explains all the connections.

google power supply datasheet c02 daniel bauen

It sounds like you have it all connected up OK but you need to set your current (milliamps) There are two ways. You can manually connect a 5K pot as the manual shows or you can adjust it as your laser machine intended.

Adjustment as intended is either a pot/adjuster or a software adjustment where you do it through the PC or control panel.

The wire "IN" goes to the thing that sets the current, either a digital chip which means you adjust in software or a potentiometer which you can turn with a screwdriver. You may need the manual or some settings software to do this.

Good luck
Keith

Walt Langhans
06-09-2014, 8:21 PM
You can manually connect a 5K pot as the manual shows or you can adjust it as your laser machine intended.

What's a/the 5K pot?

Dave Sheldrake
06-09-2014, 8:42 PM
You need to turn down the PSU Walt, I would hazard a guess it's turned right up to max-Q and is outputting the units top power.

Double check the rating for the tube and turn the PSU down or it will kill your tube pretty quickly.

cheers

Dave

Keith Colson
06-09-2014, 9:00 PM
What's a/the 5K pot?

Type potentiometer into Google and look at the pictures. You can add one of these to manually set the power You would need to leave the "IN" wire disconnected and do it as per the diagram in the power supply manual.

Pot has 3 wires. The middle wire goes to "IN". The left side goes to Gnd and the right side goes to "5v". If you get left and right mixed up that's OK, it just means you turn the pot backwards for more power.

Cheers
Keith

Walt Langhans
06-09-2014, 9:31 PM
Got it operating correctly! YEAH Joy Yang from Shenhui tech support!

Turns out there is a small hole in on the side that give you access to a screw that adjust the power of the unit. So I set the max power on the laser control pad to 99.9 press the pulse button and adjusted the power down via the screw till the amp meter read 28. It's a little late to be running the laser here, so I'll run it in the morning and see what happens.

Thanks for the help everyone!

Robert Walters
06-09-2014, 10:46 PM
Again, SOME type of manual or instruction sheet SHOULD HAVE BEEN INCLUDED!!!

Even the one I found earlier didn't mention a power adjustment setting or even a LED status display.


Walt,

Ask the guy you got the PS from to send you a manual (PDF) , then post a copy here for others in the future.

Walt Langhans
06-10-2014, 2:26 PM
I would hazard a guess it's turned right up to max-Q and is outputting the units top power.

Yup, good guess. However now I'm having issues with the lower power settings... blah... why can't this stuff ever be easy lol!

Dave Sheldrake
06-10-2014, 2:56 PM
When you say "Lower" Walt how low do you mean?, RECI's after a settling period will often not fire reliably under 15%

The setting you need is the run current and not the strike current,

Draw a line in your package, say 150mm long, set the machine on a nice thick bit of wood and run it at 2mm per second at 100% power,
After the initial strike make sure the meter reads no more than 27 milliamps as it runs, adjust the power supplies pot to compensate then always run the laser at a maximum of 90% power to allow for dirty supply spikes.

cheers

Dave

Walt Langhans
06-10-2014, 10:26 PM
When you say "Lower" Walt how low do you mean?, RECI's after a settling period will often not fire reliably under 15%

Before the new power supply I had setting in Laserworks at power 10. I never bothered to note what the amp meter was reading when it was running at this setting. However it marked MDF, Acrylic, and grayboard just fine. Now I've had to increase that 10 to a 30 to get the same results.

I looked at some RECI manuals on-line but I can find the right one for my tube. It seems it's either 27mA or 32mA for the for the high end setting. The way I have it now running at 100 from the software results in the control panel reading 98% power and the amp meter reads 27.

So I'm thinking that I might could crank it up to 32 but for the longer life of the tube I think I'm better off just upping my lower end in the software.

However with that said, I'm always up for the advice of the more experienced :D

OH YEAH... almost forgot. When I started the laser up today it ran for about an hour then stopped firing. I shut down, checked the fuse and it was NOT blown. I put it back in started it up and it ran fine for the next 10 hours so I'm hoping it was just that I put the fuse in loosely the first time, but in the interest of full disclosure I want to give you guys all the info I have.

Bruce Dorworth
06-11-2014, 1:58 AM
Walt, can you post a picture of your connections on the new power supply? There are adjustments on the power supply so you can control the max current.

Bruce

Dave Sheldrake
06-11-2014, 8:46 AM
No more than 27 Walt, 32 will shorten the tube life by quite a bit. As you say, just up the lower end in the software :) (when a tube fires it is subject to a spike, if that spike is too high you risk burning the electrodes in the tube) RECI have a max limit for warranty as well from memory I *think* its 28 but can't remember off hand.

cheers

Dave

Kev Williams
06-11-2014, 11:21 AM
This might be contrary to popular opinion, but I would think you should set the maximum output higher (32mA?) and adjust the UPPER end down in the software? I'm hardly a brain about this stuff, but it seems to me that engraving with a laser is very much like playing music with an amplifier- The main reason for high-power amplifiers in good stereo systems isn't to have more brute force to play music LOUD, it's so music can be played at 'normal' volume levels effortlessly, and the extra power is available for easily reproducing the occasional crescendo's with no effect on the lower level output.

I may be wrong, but it just seems the same would be true with your laser's controller; having a higher available maximum output let the laser work at lower levels with less effort...?

If you have a meter on your laser, it's easy to monitor your max output while vector cutting. On my Triumph, my power level set to 71% equals a solid 27mA while vectoring. I never go past this setting while vector cutting. But it's nice to know more power is there if I need it, if only for a few seconds...

Dave Sheldrake
06-11-2014, 1:45 PM
It will shorten the tube life by quite a bit Kev, when the tube fires it receives a spike current from the supply to initiate the arc / plasma, that current is relative to the PSU's run current so setting run at 32 you may well end up striking at 38 to 40.

cheers

Dave

Robert Walters
06-11-2014, 2:15 PM
This might be contrary to popular opinion, but I would think you should set the maximum output higher (32mA?) and adjust the UPPER end down in the software?

Hi Kev,

Let me tell you a little story about "computer control"...

We have these wonderful machines we call laser engravers, cnc mills, robotic welders, etc.
We do a lot of creative things with them, push them to the limits, and abuse the heck out of them.
Punch a few buttons and they produce magical objects for us.

One day a friend had a new job running on his CNC mill (BP) and hit the PAUSE button to check on something and all of a sudden all on it's own it had jumped out of "PAUSE" and jogged at full speed to it's home position.
In doing so it had caught his sleeve on the 4,000 RPM spindle and was dragging him with it.
Luckily the breaker panel was within his reach and was able to kill power.

What he found was a bug in software as he had just upgraded to utilize a new feature that was introduced.


There is a reason you will see "EMERGENCY STOP" buttons (Big Red Button or BRB as I like to call them) within reach of the operator sometimes in various spots on the machine too. They use 'Safety Relays' that are designed specifically for this and in Europe, it it required by law that they are NOT under software/computer control, and that you must use two or more in tandem in case one has a failure.

He has now installed BRB's on his mill btw =)

People are prone to error, get tired, make silly little mistakes. Relying upon software to limit peak power is prone to error. But setting the hardware to the max safe level give a bit of reassurance to that. If you really need to push to the limits periodically, it's as easy as turning a screw, then dialing it back when done.


I have seen where bypassing those safety factors cut off someone's hand when they were reaching in to clear a machine, so I'm a little bit more safety conscious than most.

Kev Williams
06-11-2014, 6:38 PM
How about this example of "computer controlled"--

The cars we all drive are equipped with an "unregulated power supply", aka "the engine", with available power much in excess than is necessary for 'normal' acceleration and driving at freeway speeds, and these engines are 100% operator controlled by a foot pedal-- and it's very likely that the pedal is entirely disconnected mechanically from the engine, because the pedal-to-engine connection is now fully controlled by the engine's computer... Pretty scary thought, actually. Would be all be safer if our engines had governors? Yes, without question. But they don't, because we don't expect or want our machinery to save us from ourselves.

We put a lot of trust in computers every day without really thinking about it...

Walt Langhans
06-11-2014, 6:43 PM
Well I've been runnin the laser pretty hard all day long, and it's doing fine. I've had to readjust some of my settings in the software but other than that it's been good to go. Thanks for all the help guys!

Dave Sheldrake
06-11-2014, 6:51 PM
Irrespective of the semantics of computer control, setting a PSU to run at 32 ma max will cause it to overcurrent for a given tube when it strikes the arc. The strike power is defined by the run current in the PSU, that's why they have limiters at the PSU's max current.

cheers

Dave