Low power output from Trumpf TLC1005 CO2 laser

[LMP2009]

Hello forum members,

We had a water leak (water + glycol) in our Trumpf TLC1005 resonator cavity (5 kW CO2 laser) a couplf of weeks back.
Found a leak in one of the eight heat exchangers in the star configuration around the turbine.
replaced the heat exchanger and pumped the cavity down a few times.
(initially it was not pumping down but finally it did - no more leaks)

Laser could start afterwords but was immidiately shutting down giving 'output power low' error. Also found some traces of moisture on the optics.
Passed warm air through the cavity for few days and cleaned the optics. pumped down the cavity a dozen times.

Since then the laser is starting ok but the power output is about 80% of the commended power and is changing linearly from low level to the highest.
plasma looks steay and good in color (purple)
All grid current and voltage values look ok

here are few more things we tried:
1. Tried to tweak output coupler to get max power out
2. Checked power out of the laser cavity to make sure the sensor isn't bad
3. tried changing gas mixes for balancing, but no change
4. replaced the mirrors and o/p coupler with the other laser we have (same type) but no change in o/p power
5. CW and pulsed gives same power. (earlier we couldn't run more than 80% in CW mode but now we can)

After all these trials and tweaks we got about 4550 W instead of usual 5200 W full power , CW mode.

I was wondering if anybody can suggest any place to look for the problem or how to increase the output back to 5kW or more.

any information will be really helpful

thanks,
best regards,
LMP2009

 

[1deluke]

LMP 2009

We also have a trumpf TLC1005. Are you getting any support from Trumpf? Can you share with us what input voltage range you are required to have for your laser. We are having flucuating wattage output problems as well around 20%. We were told by Trumpf that the input voltage must be -1% to +2%. Power company can't guarantee that! If interested in trading notes call 9377543211

 

[LMP2009]

So far Trumpf support is limited. we got the power back up to 5 kW by just repeated beam dump and pumping down the cavity over few days. (guess is that we got rid of any moisture left in the process)

is your wall voltage fluctuating or is the high voltage on the RF tube?

we have developed another problem on one of our other similar lasers (TLF5000)
cooling water temp is high in Cu circuit (T_Cr) 42 - 43C (chiller inlet and outlet are good and no error on the chiller) and the laser shuts down randomly giving 'low power output' error. Sometimes it runs at full power without any error / shut down.

Trumpf doesn't want to talk unless we 'fix' the chiller.

any suggestions?
thanks,
Harshad