this morning with Daniele, we are measuring the amplifier power just before the FP-cavity.
Casemate temperature @19.5°C

@0% : 205mW
@10%: 755mW
@20%: 7.44W
@30%: 14.3W
@33%:16.3W
@40% : 20.3W
@50% : 24W
@60% : 26W

=> there is a power issue !!!

the normal casemate temperature should be in between 21 and 22°C.
cf this post (https://elog.lal.in2p3.fr/FPC/THOMX+commissioning/133) to get previous amplifier power.

=> it seems we need to redo the compressor CVBG alignment !
first, we will check the amplifier power before the compressor.

after doing some alignment (walking procedure on the Y axis), and CEP optimization, I got 83kW for 33% on the laser amplifier with a coupling of ~60%

=> we have to check the input power after the amplifier.

I adjusted the FP and laser cavity motors to have a small 33MHz detuning with the RF reference (~10 Hz of beating @ 33MHz)

pb : I don't see the 500MHz beating signal => to be checked

during the motion of the FP-cavity motors, I observed a systematic delock when moving MOT.06 on P1z and no delock with MOT.03 on P4z when I move by 10 steps.
Kevin checked that both IcePap controller have the same configuration and then, the problem is maybe coming from the rust observed on the mechanic.
 

we had to move the laser cavity motor to find the resonances and change a lot the CEP.

the CEP motor is at -524.1µm

we got ~75kW in the FP cavity without alignment but with CEP optimization.

the coupling (the cyan color) is ~ 62% !

=> we need to do some alignment

I refilled the chiller and the stabilized temperature is @ 25°C

we started the 3rd stage of the Alphanov amplifier at 30% => PD_OUT is fluctuating around 1-1.4W => it's not related to the real output power !

the photodiode connected to the scope CH2 is around 210mV @ 50ohms

we clearly see some small peak on the transmission signal (scope CH1) => we need to optimize the laser cavity length and the CEP

temperature in the casemate ~ 19.5°C stable

this morning, I measured the power directly at the output of the fiber coupler (through the output fiber), after the strecher : ~5mW
then, I connected the EOM used for the PDH technic : ~2.5mW
then, I connected the fiber of the EOM to the Alphanov amplifier input fiber.

LAL Alphnov software :
PD_IN           = 3.289mW
PD_PULSE   = 33.372MHz

=> nothing to do ! :-)))

I switched ON the preamplifier (3rd stage @ 0%) => PD_Preamp2 = 152.44mW

Guillaume and Julien Bour from Alphanov will come on wednesday 24/07 to have a first look and check the amplifier.

to prepare their intervention, I tested this morning the OneFive oscillator : it's still working at 33MHz.
and we have ~5mW in the LAL software without the EOM.

so, we are in "standard" conditions.

the present situation is :

Guillaume asked me to disconnect the "Laser head" cable from the pump diode module, installed on the optical table.
on the pump diode module, the connector has several small pins and 3 larges pins : A1, A2, A3.
if the diode of the preamplifier (not the ones of the last stage) is alive, the impedance between A2 and A3 should be around 5 ohms and not HiZ.

I checked several days ago the impedance between all these 3 pins to avoid any error on the schematics.
the impedance is always HiZ.
then, Guillaume thinks the diode is dead.

we are waiting for further tests or procedure.

FYI : to access special menus on the Alphanov software,

login : "Administrator"
pwd : no password

to modify parameters in these special menus :

login : "Alphanov"
pwd : "AE32HF56J"

Yesterday, we received the controller back from Alphanov
and I tested it immediately in the optical room.
if the software is properly talking to the controller, everything works normally.
then, one just have to remember that is mandatory to have the software properly connected to let the controller start electrically (power supply activated on the main boards)

Today, I installed it in the casemate with all the connections to the laser input, output, laser head, safety connections, etc...
and it works properly.

- The power in the fiber from the strecher is at 6.3mW.
the software reads 5.3mW but after a long fiber... then it is OK.
=> one strange thing : it detects 100MHz instead of 33MHz => to be reported to Alphanov !

- Amplifier output power measured after 2 mirrors :
0%                 =>               230 mW
10%               =>               880 mW
20%               =>               8.8W
30%               =>               17W

which are the numbers we had before.... then we are back to normal conditions to continue the commissioning.

today, I tried to restart the amplifier at 0% (without 3rd stage) but it didn't start... still the same error message.

but the PD_IN power and the PD_PULSE frequency seems correct.... I will try to power the amplifier OFF and ON later to see if one can reset this error.

edit : finally, a the end of the day, I switched OFF and ON several times the amplifier but I always get the same error message "bad sequence error".
I tried to use the Alphanov software to see if we can get more information about the error :
the watchdog LED is RED => I have to check if it is normal or not before starting the amplifier
and the PD_CRI LED is RED => normal because the preamp stage is not started (and it does not want to start...)

PD_IN is at 3.1mV but a previous post says that the amplifier worked with 2.7mV.
we can try to increase to 3.2-3.3 mW and see if it works....

edit : it seems we already had this kind of error before.
Guillaume suggested to check the average power of the seeder at the output of the fiber, the repetition rate and the stability of the signal.
previous post (https://elog.lal.in2p3.fr/FPC/THOMX+commissioning/179) have shown an input power (PD_IN) around 5.7mW (see the attached image) !
this power was maybe obtained without any EOM which divide the power by ~2.
=> we can try to remove it temporarilly to check if the amplifier is able to restart in this condition... to be done

the air temperature is between 21°C and 22°C.

I tried to lock the cavity but it was very instable with only short time locks.
I had to increase the parameters of the PID:
P = 0.07
I = 0.0007
D = 0.706
after that, the lock was stable but we can see something in transmission (dark blue curve) which seems to be a degeneracy.

maybe because of the water cooling temperature, after stopping the laser amplifier, I was not able to restart it.
I always got an error (an alarm was triggered by bad sequence) when I want to switch ON the preamplifier at 0%.
the Temp Amp 1 is about 25-26°C... it is stange.
to be tested after the water cooling is repaired.

Yesterday, the ThomX water circuit should have been repared,
and yesterday aftenoon, Daniele restarted the chiller and I checked it this morning without any error.
BUT the pump of the ThomX water circuit is again in default...
Dalkia has been called to fix the problem.

despite this point, I restarted the laser amplifier this morning.
everything seems as usual and I can see some small resonance at the output of the Fabry-Perot cavity
BUT the reflection photodiode level doen't change when the amplifier is ON.
I need to check if the photodiode switch is set ON or if it is misaligned or dead.... to be checked.
in between, I prefer to stop the laser amplifier.

edit : the photodiode problem was coming from the PhD power supply which was OFF.
I just turned it ON.

this morning, the chiller was in error and I had to restart it.

the air temperature is around 21°C.

the water cooling has been repaired but the initial Temp Amp 1 is at 28°C.

I got 86kW in the FP-cavity with 33% of laser amplifier ratio after tuning the CEP and the alignment.
but the amplifier stopped after an error after 30 minutes => the Temp Amp1 reached 30°C => it's not normal.
the chiller was again in error. I tried to restart it but I got an ERROR14 : Thermostat error, the flow rate is zero !!!
the tubes for the inner circuit going to the amplifier are a little hot by touching them with my hand.
the tubes for the outer circuit going to the ThomX water circuit is hot for the "blue" tube et cold for the "yellow" tube.
it means there is no flow in the outer circuit.
Jean-Noel just told me it's normal because he stopped the ThomX water pump because of a too high temperature => Dalkia should fix the problem today.

OC/OP/OCH.01-MOT06 roughly at position -792 600 steps.
CEP motor = -211µm

the OC/OP/OCH.01-MOT03 is still faulty => to be fixed by Kevin.

this morning, the computer was restarted and I had to launch all the applications.
no problem except the powermeter for which I had to do a power switch OFF and ON remotely.

the chiller was in error and I had to restart it also.

the air temperature seems to be not properly controlled (see the picture)
one can see a constant temperature drop from Tuesday 9 April 10:30am.

it seems the water cooling is also not working properly as I saw the laser amplifier temperature (Temp Amp 1) increased constantly during the run from 24°C to 30°C (in 30 mintues).
=> it's not normal, it should be regulated at 25°C !

I got 89kW in the FP-cavity with 33% of laser amplifier ratio after tuning the CEP and the alignment.

OC/OP/OCH.01-MOT06 roughly at position -782 000 steps.
CEP motor = -425µm

the OC/OP/OCH.01-MOT03 is still faulty => to be fixed by Kevin.

this morning, I had to restart the chiller. Temp Amp 1 is at 27.5°C after having started the amplifier at 33% ratio.

I removed the 100kohms resistor on the Transmission channel, on the scope (now, it is 1Mohms), to get more sensitivity.

the air temperature is around 21°C and is stable during the last days.

I don't see any power coming from the amplifier despite it is at 33%... I think the MPS prevent us to work and the amplifier shutter is blocking the beam.
I will send an email to Sophie to check that point.

EDIT : Kevin showed me how to acknowledge the error on the MPS
=> go to "Detail" and then acknowledge the "vacuum error".

I saw the FP-cavity resonances but I didn't have time to optimize them as the water temperature is still too high and the chiller is not working good enough.
=> the amplifier did a safety stop.
one needs to wait this issue is fixed.

OC/OP/OCH.01-MOT06 at position -790 000 steps.
CEP motor = -300µm but far from the optimum CEP position.

from now on, the transmission factor for calculating the FP intra cavity power is 1/1.75ppm ~ 570 000 (changed in the Powermeter software)

this morning the temperature of the water cooling circuit is still very high said Sophie, and the laser amplifier temperature "Temp Amp1" is at 29°C instead of ~23-25°C
then, when I start the laser amplifier, it stops rapidly with a warning error.
I will check the chiller status as the Dalkia should fix the water temperature problem at some time (Sophie + Alice working on this point)

the air temperature in the bunker is back at 19.5°C from last Friday afternoon and is stable at less than 0.5°C.

after restarting the chiller, the "Temp Amp1" is now at 25°C before starting the power in the amplifier, it rises at 28.5°C after some minutes
I found the resonances with the motor OC/OP/OCH.01-MOT06 at position -783 460 steps.
and I had to tune the CEP to get the maximum resonances at -198µm.

with the new transmission factor, I got almost 90kW for 33% laser amplifier ratio after a simple alignment procedure.

the motor OC/OP/OCH.01-MOT03 is sill in error.

This morning, I locked again the FP-cavity at more than 50kW with 33% of laser amplifier ratio.

the temperature is measured today at 20.5°C despite the fact the air conditionning is still OFF.
the temperature, rising from 18°C, started monday at 11AM roughly.
maybe, the difference comes from the external doors of the Igloo which have been closed recently ? to be confirmed.
as the temperature is measured inside the airflow housing, all the powered equipements are disspating some heat, rising the inside temperature compared to the bunker temperature.
EDIT : Sophie Chance told me the water temperature cooling of ThomX was defective... the water temperature went to 29°C ! it is being fixed by Dalkia.
careful, we don't have a temperature measurement of the water going to the chiller...

to find resonances, I moved the OC/OP/OCH.01-MOT06 motor from position -770 000 steps to position -788 600 steps which corresponds to ~100µm !
it can be explained by the temperature change and also because during the lock last week, I let the MOT06 motor in position after the cavity was at 50kW.
I had also to change the CEP motor position from -170µm to -420µm and to do some alignment (with walking procedure).

accessing the motor OC/OP/OCH.01-MOT03 from the ATK panel, produces an error : "connection to device failed"... to be solved by Kevin ?