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argon-ion
04-17-2009, 08:03
Yes you've guessed it folks, yet another one of those "doesn't work" questions from a newby.

Firstly can someone guide me through the start up sequence for the Spectra 261 B argon Ion. just in case I am doing something completely stupid. Let me know what all the LEDs mean, and should they be lit or not !

( and when should they be let and when shouldn't they ! )

Symptoms are as follows : only standby led comes on. no others, all fans work, switches set to "light" and " local" ( usual two pins on remote jumped). turn key, meter jumps off the scale (12A+ ) , after 30 odd seconds PSU internal relay heard to click once and laser head then starts to tick continuously. no light emission. After 20 odd ticks I switch off using the key ( let fans run), so not to trash PSU.

playing with the variable current pot on the side of the PSU has no effect.
cannot see what is going on inside the tube as it is metal ! however element checks out OK.

best regards.
all replies appreciated.

argon ion.

keeperx
04-17-2009, 08:15
maybe its out of gas...

buffo
04-17-2009, 08:43
Firstly can someone guide me through the start up sequence for the Spectra 261 B argon Ion. just in case I am doing something completely stupid. Let me know what all the LEDs mean, and should they be lit or not !
Hi Argon-Ion! Welcome to PhotonLexicon. I've owned a few 261B's, so I can offer you at least a little advice. First, I'm assuming that you've either got the remote connector hooked up, or else you've shorted the correct pins on the remote socket. See this pic (http://www.photonlexicon.com/gallery/v/users/buffo/sp261/DSCF0599.jpg.html) in my gallery for details. (The remote socket in the picture is from a 263 PSU, but it's identical to the one on a 261B PSU.)

When you power it up, the standby *and* interlock lights should both come on. Then after a ~30 second delay you'll hear the relay click, at which point the tube should light and the lasing and regulation lights should come on.

Symptoms are as follows : only standby led comes on. no others, all fans work, switches set to "light" and " local" ( usual two pins on remote jumped). turn key, meter jumps off the scale (12A+ ) , after 30 odd seconds PSU internal relay heard to click once and laser head then starts to tick continuously. no light emission. After 20 odd ticks I switch off using the key ( let fans run), so not to trash PSU.
Only two pins shorted? The ones on the bottom? What about the ones in the middle? Check the picture in the link above. There should be a pair of pins shorted in the middle row on that socket. (*Some* PSU's don't have these pins, but if yours does, then they need to be shorted or your Interlock light won't come on.)

The fact that the current ramps to 12 amps when the ignitor fires is troublesome. If there is really that much current traveling down the bore, you should at least be getting flashes of light, though it would be possible that the current is ramping up too high, causing the PSU voltage to drop off, which would extinguish the discharge in the tube - at least until the next ignitor pulse. But you'd still see the flashes on the wall... BTW, the ticking you hear is the ignitor in the head firing. (Should be a couple times per second.)

Try switching the PSU to current mode and see if it will light that way. (Be sure to turn the current control pot to the middle of the range.) If it lights that way, then you've got a problem with the light feedback circuit. Run it in current mode and you'll be OK.

If you can't get it to light even with the PSU in current mode, then you may have a blown current regulator in the PSU. I had a similar problem with one of my units. To work around the problem, I put a large nichrome wire resistor in series with the head. This dropped the current down to around 8 amps, and the tube would stay lit that way. But I never got around to fixing the current regulation stage in that PSU...

Adam

argon-ion
04-17-2009, 10:00
Cheers Buffo,
Just what I needed, some sound advice , much appreciated. thanks for the quick reply.
Pity I have downed a bottle of red this evening ( yes, Im in the UK) otherwise I would get to work immediately. Booze and volts don't mix... been there , done that ! ..... learnt my lesson.
I have no other pins apart from the two bottom right jumped so I will try this first.
current mode does not help.
I will report back tomorrow.
thanks again argon ion

buffo
04-17-2009, 10:04
No problem - glad to help. I agree with your assessment that booze and volts don't mix though! ;)

Post your results tomorrow and we'll go from there. Though if it's not something simple like shorting the extra pins, then I'm afraid you'll need to dig into the PSU to find the problem, and I'm not familiar enough with the innards to be of much help there...

Adam

argon-ion
04-17-2009, 11:17
Dear Adam
If I really am hitting my head against the wall over this, I will try substitution, I think that there is a saying something along the lines of : " given enough monkeys and enough typewriters .... one will get the works of Shakespeare...." this translates into given enough PSU's and compatible tubes there will be blue light !

I have not operated on the PSU yet, ( nice bullet holes in your 216B ! pics , ), I have checked fuses they are OK, but need to remove metal plate that hold the 2 vertical cards in place, there are two large metal tranies / thyristors on the vertical cards which will be the first items to check, crumpled and brown copper board tracks might also give the game away.
It's all to tight to inspect without disassembly. Electrolytic capacitors dry out with time and this PSU is crammed full with them, that would be a cheap fix. As nothing appears to be getting hot, I am really phased by where all that current is going... the power meter is maxing out at 12 A, doesn't mean to say its 12 A , could be more, much more... 12A even for 40-50 seconds must get something hot. Could be the fans are really effecient.

going back to your pics of the 216 PSU, do the splashes of white paint on the control panel make a difference, I only have a few dollops of grey primer on mine.... is this a garden workshop thing, or a phenomenon new to quantum physics ? is the laser wattage inversely proportional to artistic content of the painted image or the square root of the area obscured by overspray ?
If we can put this to a vote, can the former be called Carters Law. In which case I will cover the whole PSU in dayglo orange. ..... you heard it here first Folks, go faster stripes for lasers. Roll up , Roll up,.... only 5 bucks a set.

I will report back tomorrow.. hopefully with some good news, Only kidding about the Orange, (dayglo green would look much better)

regards. argon ion.

keeperx
04-17-2009, 11:49
i stuck an AEM (http://www.aempower.com/) sticker on my 99 saturn and gained 30 horsepower. Imagine what will happen when i put a nice heavy spoiler on it.

argon-ion
04-17-2009, 12:38
I put stickers (sorry , decals) on racing spoilers for a living, need the down force in the corners but the job does become a drag when doing the straight bits ..... (think about it..... ), don't get it, don't worry it's not really funny, and nothing to do with cross dressing transvestites more to do with aerodynamics, as I said not funny really. Flexiwings were funny, they would snap of at 200 Mph due to fatigue and the car would hit the barriers on the next bend.... not good. Should have cut the Carbon fibre with an industrial laser, not chomped it with scissors.

On that point any of you guys bought or used an epilogue / Universal C02 laser for some serious cutting of signage acrylics / carbon fibre / composites ?

regards.
argon Ion

keeperx
04-17-2009, 12:49
hrm.. that might be the type that Mark (imagelight) has access to. he used to work for a sign making company that had some sorta 40w (not sure if thats accurate) CO2 with a big moving table of sorts..

he still has access to it..

argon-ion
04-17-2009, 13:12
40 to 80w is the norm, nothing too large. basic machines start at 25 W, and to be honest the thin gauge stuff I cut (being kapton and Mylar for aerospace use ) is happily cut at 25W. The machines are no more than a flatbed pen type plotter, i.e. a an X-Y bed with a set of mirrors and a focusing lens... but they are just so expensive, the Chinese are flooding the market with cheap 40 w C02's (cutters and engravers) but I need professional kit capable of cutting to a very fine accuracy... repeatedly. I have had a days use on a Versalaser, which was good, couldn't fault it... just the price. Ouch !
I need to talk to someone first hand, see what preferred.

regards Argon ion.