New toy! Lightwave M612

[macona]

Got myself a new toy. I posted about that lot of lightwave heads. Well, I got one of them, one was different than the others, q-switched 532nm output instead of 335. Found a couple problems. One was the coax connector for the q-switch in the AMP connector was pushed back in where it would not make contact. Second one of the CPC water connectors on the head was broken internally and ways probably not letting full flow, if any. So I fixed these two issues. I also got a couple thermoelectric chillers, both were prototypes from china for a local laser company that used these heads. I found the pinouts for the chiller connector on the power supply on laserfaq.

Darn thing works. Has 1489 hours on the head. According to the built in power meter I am getting a pretty stable 5 watts at 10khz. An external power meter head is telling me about 6 watts. Don't know what to believe, I will stick with the lower of the two. I am thinking the two problems I found might have been why the head was taken out of operation. Seems to be outputting what it was designed for from the label.

Yes, I do have laser googles. OD11 & 514nm.

Couple of pics. Firing it onto a piece of EDM graphite.


IMG_2282 by macona, on Flickr


IMG_2283 by macona, on Flickr

[Diachi]

That's an impressive beam! Taken any size measurements?

[macona]

It is tiny. Sub-mm in size. The current model is rates for a .35m beam at 2.2 mrad. I am still waiting for the manuals from jdsu.

One thing I have to figure out is I get a "Low reservoir" warning that pops up after a while, something related to the chiller. So I tried the spare power supply. Still the same issue but the head seems to be more stable with this power supply holding at over 6.5 watts.

[macona]

Found the issue with the low reservoir warning. Hooked up the chiller bypass wrong. Oops!

These chinese chillers are a joke. I have already had to do some redesigning. I can see why they never went into production. The PC boards are not bad, everything else, well...

The water reservoir on one is just a drinking bottle at an angle with fitting glued in place. Hoses are electrical taped together. Had a problem with the smaller of the two, one of the power supplies kept overloading. It has two 24v, 15amp power supplies in parallel. Well, it seems these power supplies do not like to be paralleled. One takes the whole load instead of sharing. Even putting diodes in between did not get them to behave. The power from the supplies is fed to a board with 6 relays and a driver IC. The power is all on a common bus. So I took a knife and cut the traces on the positive side and ran half the TECs on one power supply and half on the other. Much better. The power supplies are much happier. They were making funny noises when they were tied in parallel too.

One problem was the larger of the two chillers does not have enough capacity for the laser head. The diode temp creeps up past the specced temp and the laser looses efficiency with the wavelength out of whack. So I decided to tie the two in series. I replumbed the small chiller to bypass the pump and the reservoir and put this in series with the big chiller. The next problem is that the small chiller only goes down to 18 degrees c. The diode needs to be at 17.3, so that aint going to work. The temp is read with a NTC thermistor on the line. So I stuck a 30k resistor in parallel with the thermistor which offset the temp by about 10 degrees. The temp is not critical. I could have bypassed the control altogether but I wanted to keep the I/O connector on the back useful. The power supply for the laser has an output line that would control the refrigerant valve in the chiller. I used this to control a small signal relay to close the chiller on/off inputs. The power supply then controls the diode temp with the chillers with it's own PID loop.

So, now that I got the chillers under the power supply control the output has really stabilized. I now get a consistent 6.6 Watts at 10-12Khz. That's a lot of green! Water temp runs about 12c.

This afternoon I did shoot it outside to get an idea of the beam size. At about 40' it is about 1" in diameter. And left a nice dime sized scorch mark on the wood fence that was my beam stop after a couple of minutes!

[planters]

This is a very nice sized laser. Great beam specs if that kind of divergence is from an initially 0.35mm beam. What are your plans? Any thoughts re pumping dye etc?

[macona]

Heck if I know what I am going to do with it. I got it expecting one of the 335nm lasers, not 532.

I have been playing.. err.. experimenting. I can mark pretty much any metal, even clear anodized aluminum. I have managed to just make it though a .013" feeler gauge. Cuts Kapton pretty nicely, much finer than a CO2.

[catalanjo]

Cool that seems like the LPF version of a machine gun.
Bet U can pop balloons in enormous quantities.

Seriously I agree with Planters ... bung it through some free running R6G and get a really gorgeous looking copper coloured beam out the front. Makes me go as green as the pump beam just thinking about it!

Cheers

[macona]

I don't know, I am so full of hot air that if the balloons don't immediately ignite on contact the float away!

Been thinking about a dye laser. But from that other thread about them I have second thoughts. I would only attempt it if I found a used head.

[macona]

Here is a pic of the power supply and the chillers. The power supplies were OEMed for a certain company that used these lasers in their product. They intended to scrap them but they allowed us to buy them if we removed the front panel which has their name on it. Luckily it was a simple job and it really did not hurt the functionality of the power supply.


M210 Power Supply and Chillers by macona, on Flickr

[gotwin]

Hello,macona !
Can you give me the M210-HD-V06( OR M210-PS-V06 POWER) Diode pumped laser power suppluy manual and M210-HD? Please email me at cdgotwin@126.com!

Thanks! Jerry