As we learned yesterday, the PSL laser power out put mechanical shutter is not working in the remote mode. It only works in local manual mode.
Do not rely on the MEDM screen monitor readout! The position is only changing on the monitor. The main beam must be blocked before the output periscope.
Ben found the Sorenson 5V ps off. It was turned off since our last scheduled power outage. I wonder what else is running on 5V in the PSL? This power supply should be on the
"alarm handler" list to avoid future repeat of this condition. However a real safety switch would have confirming position sensors of the shutter open or closed. Is there such thing at the sites?
Please don't go down the Yarm (Old Xarm) for right now, or if you do, please be very careful. Kiwamu and I are set up to take beam scan measurements down the walkway, and so there are some cables / carts / other stuff down there. We are going to get dinner really quickly before beginning the measurements.
Right now, the PSL shutter is Closed, so there is no beam hazard outside of the chambers, just crowded space hazard.
Nancy and Sharmila received introductory early bird surf safety training for the 40m lab.
The 40m corner station crane is out of order, and it's stuck in a way that prohibits entry to the 40m LVEA / IFO room for safety. The crane has been locked out / tagged out.
Until further notice, absolutely no one may enter the 40m LVEA. Work is permitted in the desk / control room areas.
Signs have been posted on all doors into the LVEA. Please consider those doors locked out / tagged out.
[Steve, Kiwamu, Jenne]
The 40m is now back in Laser Hazard mode. Safety glasses are required for entry into the LVEA / IFO room.
The insects and the laser trouble... Strange coincidences with LHO surprised me, but now I have been relieved.
40m SURFs Razib Obaid, Nancy Aggarwal, Unknown Bearded SMURF, Megan Daily, Gopal Nataraj, Katharine Larson and Sharmila Dhevi received 40m specific safety training on June 23, 2010.
The 1 Ton yellow crane support beam jammed up at Friday morning, June 25.
The 40m vertex crane has a folding I-beam support to reach targeted areas. The rotating I-beam is 8 ft long. The folding extension arm gives you another 4 ft.
The 12 ft full reach can be achieved by a straightening of the 4 ft piece. There is a spring loaded latch on the top of the I-beam that locks down when the two I-beams align.
This lock joins the two beams into one rigid support beam for the jib trolley to travel. The position of this latch is visible when standing below, albeit not very well.
To be safe it is essential that this latch is locked down fully before a load is put on the crane.
We were preparing to pump down the 40m vacuum system on Friday morning. The straight alignment of the 8 and 4 ft piece made us believe that
the support beams were locked. In reality, the latch was not locked down. The jib trolley was driven to the end of the 12 ft I-beam. The 200 lbs ITM-east door was lifted
when the 4 ft section folded 50 degrees around the pivot point. This load of door + jib-trolley + 4 ft I-beam made the support beam sag about 6 inches
The door was removed from the jib hoist with the blue Genie-lift. The sagging was reduced to ~3".
The Genie-lift platform was raised to support the sagging crane jib-trolley. The lab was closed off to ensure safety and experts were called in for consultation. It was decided to bring in professional riggers.
Halbert Brothers, Inc. rigging contractor came to the lab Tuesday morning to fix the crane. The job was to unload the I-beam with safety support below. They did a very good job.
The static deformation of I-beams sprung back to normal position. There are some deformation of the I-beam ~2 mm where the beams were jammed under load.
It is not clear if this is a new deformation or if the crane sections have always been mis-aligned by a couple of mm.
The crane was tested with 450 lbs load at 12 ft horizontal travel position. The folding of I-beams were repeatedly tested for safe operation. Its a 1 ton crane, but we tested it with 450 lbs because that's what we had on hand.
We're working on the safety upgrade of this lift to prevent similar accident from happening.
Atm 1) load testing 2007
Atm 2) jammed-sagging under ~400 lbs, horizontal
Atm.3) jammed-folded 50 degrees, vertical
Atm.4) static deformation of I-beams
Atm.5) unloading in progress with the help of two A-frames
Atm.6) it is unloaded
Atm.7-8) load testing
Atm.9) latch locked down for safe operation
Atm.9) zoom in of the crane sections misalignment
All 3 cranes will be load tested at 1 ton tomorrow morning between 9am and 2pm
Do not come to the 40m lab during this period. We may disturb your experiment.
Please prepare your touchy set ups to take this test.
Head count at the evacuation drill today. I checked alarms and flashers at room 104,102,101, 103, 105 and 107. They were really loud and bright.
I hooked up interlock to the Innolight 2W 1064 nm in the enclosure. The manual shutter is closed on this unit.
SAFETY GLASSES REQUIRED !
Innolight 2W 1064nm main laser was turned off for more enclosure related work.
The electrician re rooting the power- conduit to the interlock under the floor and bring it through the new concrete tunnel.
Emergency laser power shut off switch was tested at entry door 104M. It worked fine.
No laser glasses required. Laser will be turned back on around 11 am today.
Atm1, AC power line to enclosure and interlock was extended.
Atm2, 24V line to interlock rerouted
Atm3, job is completed
SAFETY GLASSES REQUIRED ! SAFETY GLASSES REQUIRED!
The laser is turned on. Injection current set to 0.871A.
Actually some one turned the laser off last night and did not enter it into the elog ! Burned toast award is granted !
Please come forward voluntarily.
I turned off the laser last night to protect against the electricians. but failed to elog it. I accept the burnt toast completely.
The control room's north west corner smelled like propane gas yesterday around 16:30
We all agreed that the smell was real and I called the safety office. I was told that they received 6 other calls from different parts of the campus.
The smell disappeared in about a half an hour.
Our visiting graduate student Yuta Michimura received 40m specific basic safety training today.
Our new undergrad Joonho Lee received 40m specific basic safety training yesterday.
Yuta and Joonho are scheduled to participate in the LIGO-laser safety tutelage with Peter K on Oct 12
The 2 W Innolight shutter is closed and enclosure door removed. Beam path blocked. Do not change this condition.
The PSL output beam guide was upgraded from 2" to 8" OD . It is green ready. Shutter is open.
Yuta, Joonho, and Suresh received the Basic Laser Safety Training from Peter King today.
Now, we got homework.
Our new postdoc Suresh Doravari received 40m specific safety training last week.
I blocked the AP table's south west 10" ID port since it is obsolete with the new layout.
Reminder: items on the enclosure self can fall down in an earthquake. I moved oscilloscope and heavy calorimeter head from the edge of the cliff.
The #3 enclosure door was removed for the carpenter shop this morning. They will make 5 full size doors with window on each.
TEMPORARY aluminum sheet is clamped into its place. This sheet should not be removed till new doors arrive.
The inside Formica color will be changed from white to black to reduce the green scattering.
Larisa Thorne received 40m lab specific, basic safety training. She will attend P. King's Basic Laser Safety Training Session tomorrow.
The beam of IR for doubling is clipping on bnc cable to green beam transmitted pd.
Bryan Barr is visiting us from Glasgow for a month. He received 40m specific safety training on Friday.
Mike Caton of Konecranes inspected and loadtested all 3 of the 40m cranes at max reach trolley positions with 1 ton.
Konecrane representative gave crane operator training in the 40m. Koji has become a qualified, trained crane operator of the 40m lab.
The emphasis of this annual safety audit was on safe electrical housekeeping on March 3, 2011
1064 nm transmison were measured of 40m safety glasses as shown . Their performance did not degrade. They are as good as their labels.
40m surfs: Nicole Ing, Iswita Saikia and Sonali Mohapatra received 40m specific safety training today.
Yesterday, I fried the +15 V power supply rail on one of the Eurocrate extender cards while I was checking out the binary switching in the 1X5 rack. I will describe what I did it in the hopes that everyone else will be less stupid than me.
I wanted to monitor the voltage across a resistor on the suspension OSEM whitening board. Since I knew that both sides of the resistor would be at non-zero voltage (including possibly at the power-supply rail), I used a battery-operated scope with floating inputs, so that the scope would not try to pull the probe shield to ground. That should be OK, although not recommended, as you'll see, because you must be very careful to make sure that the scopes inputs are indeed floating.
Let's call the original signal 'A'. The trouble came when I then connected another signal (B), whose shield was connected to the ground on the whitening board, to the scope. Apparently the grounds on the scope inputs are connected, or were in the configuration I was using. When I connected the signal B, B's ground shorted A's shield to ground, which had been sitting at the +15V rail. That short circuit then fried the +15V supply line on the extender card I was using (escaping magic smoke was detected). Thankfully this only blew the extender card, and not the Eurocrate or the Eurocrate power supply or the whitening board or the scope etc, all of which would have been much worse.
The moral of the story is to be very careful when connecting power supply voltages to the shield or ground of a scope. In short, don't do it. I didn't ultimately need to, since I could have found other ways to measure the same signal.
Lightwave M126-1064-700 lasers sn415 at east end of the Y arm and sn201 at the AP table are connected individually to one each EMERGENCY LASER SHUT OFF SWITCH.
I found baked allen keys on the top of the clean optics cabinet. Somewhat heavy box that can come down in an earthquake on our heads.
NOTHING SHOULD GO ON THE TOP OF THE CABINETS OR RACKS except small plastic boxes that storing our clean clothing.
Today I learned some important circuit-building lessons while testing my photosensor circuit box (i.e. how NOT to test a circuit and, conversely, things that should be done instead).
I blew my first circuit today. The victim is in the photo below (bottom 7805 voltage regulator). The plastic covering fell off after I removed the fried regulator. After checking various components, I figured out that I blew the circuit because I had forgotten to ground the regulator. Although this was very unfortunate, I did make an important discovery. While testing the voltage output of the 7805 voltage regulator (I put a new one), I discovered that contrary to the claims of the datasheet, an input voltage of 5V will not produce a steady 5V supply. I found that at 5V, my regulator was only producing 4.117 V. I was using a 5 V supply because I wanted to use only 1 power supply (I was using a two-channel power supply that had a fixed 5V output to produce the +15, -15, ground, and 5 V I need for my photosensor circuit box). After seeing this, I got a second power supply and am now using 10V to as an input for the regulator to produce 4.961V. I found that from a voltage range of 10V to 15 V, the regulator produced a steady 4.961 V supply. I have decided to use 10V as an input. My newly-grounded voltage regulator did not smoke or get hot at 10V.
After several more debugging trials (my LED was still not lighting up, according to the infared viewer), I learned another painful lesson. I learned DO NOT USE CLIP LEADS TO TEST CIRCUITS!!!! Initally, I was powering my circuit and making all of my connections between the photosensor head (2 photodiodes and 1 LED) with clip leads. This was a BAD IDEA BECAUSE CLIP LEADS ARE UNSTABLE AND IT IS VERY EASY TO SHORT A CIRCUIT IF THEY ACCIDENTALLY TOUCH! I did not realize this important lesson until my photosensor circuit was once again burning. Confused as to why my circuit was once again burning, I foolishly touched the voltage regulator. As you can see on the top voltage regulator in the photo below, my finger left its mark on the smoldering voltage regulator. As you cannot see the wincing on my face as I try to type this long elog, I will painfully type that the voltage regulator left its own mark on my finger (an ugly sore little welt). Suresh has taught me a valuable lesson: WHEN DEALING WITH SOMETHING OF QUESTIONABLE/UNKNOWN TEMPERATURE, USE YOUR NOSE, NOT YOUR FINGER TO DETERMINE IF THAT COMPONENT IS HOT!!!!
To make my circuit-testing safer, upon the suggestion of Suresh, I have since removed the clip leads and inserted a 12 pin IDC component (pictured below). There are 12 pins for the 6 inputs I will get from each of the 2 photosensor heads. I have requested orders for a 16 pin IDC connector, 15 pin Dsub male part, 15 pin Dsub feed-thru, 9 pin Dsub male part (2), and 9 pin Dsub feed-thru (2). After receiving these components, I should be able to safely test my circuit.
In the meanwhile, I can explore SimMechanics and try to figure out how to use the accelerometer
There is should be a few IDC connectors in the lab (and some ribbon cable) using which you can proceed with the testing of the circuit, if you prefer. If not we can get them from our ever helpful electronics division at Downs. In any case there is no need to lose time waiting for parts to arrive.
Our surf student Manuel Marchiò received 40m specific safety training today.
The hazardous waste people are moving chemicals around outside our door, and have roped off our regular front door.
Please go around, and use the control room door to enter and exit. It is currently unlocked, although I'll lock up when I leave for LIGOX.
Paul, Mirko and Katrin visiting grad students received the 40m basic safety training.
First aid kits are located close vicinity of entry doors and under circuit breaker panels.
Bob, Callum and Daphen noted that our keeping a JDSU HeNe (max power <4mW) is against somebody's SOP. So I cleared everything that relates to 40m SOS suspending to the bottom shelf of the 2nd cabinet in the cleanroom (the back set of cabinets nearest the flow benches). The door has a nifty label. Things that are in there include:
QPD and micrometer mount
microscope and micrometer mount
Al beam block
Magnet gluing fixture
dumbbell gluing fixture
The electronics that we use (HeNe's power supply, 'scope, QPD readout) are still on the roll-y thing under the flow bench.
It started with fire alarm test yesterday at 14:50 All alarms are functioning VERY loud and their flashers are bright. Evacuation drill followed. We assembled at north west corner of the 40m building and counted 6 heads.
Nobody was left sleeping inside. Bob carried the success report of the drill to PMA office immediately.
Emergency exit lights were inspected: 2 out of 13 batteries have to be replaced
One of the Halon fire extinguishers needs to be recharged out of 8
Please do participate in preparation for the upcoming safety audit on Feb 28
Batteries replaced and cylinder recharged. Please clean up your experimental set up if it is blocking breakers or entry way etc.
I will start the final clean up 2pm today.
Correction list by visiting safety committee, Haick Issaian is not shown:
1, update laser, crane operator list and post it
2, check fire extinguishers monthly, date and initials must be on the tags
3, move drinking water tower so it does not block fire extinguisher
4, post updated crane doc at cranes
5, post present phone lists at IFO room phones
6, emergency laser shutoff at the south end must be mounted without C-clamp
7, use heavy cable tie to insure position of mag-fan on cabinet top
Additional to do list:
a, safety glasses to be cleaned
b, let the electrical shop fix Rack-AC power to optical tables at the ends
c, measure transmission of laser safety glasses
d, update IFO outside door info signs
e, update laser inventory and post it
f, schedule annual crane inspection and renew maintenance contract
g, PSL enclosure inner shelf needs a good clean up so it is earthquake safe
Today I've attended the laser safety seminar.
ETMY sus damping was disabled. Green locking laser and associated electronics turned off. Computers and power supplies turned off at rack 1Y4
The electricians picking up ac power from 1Y4 manual disconnect box and installing conduit line to ISCT-ETMY east end optical table.
There will be no more daisy chaining this way.
The power is back on at ETMY . c1iscey has not been restarted.
Now I'm turning ac power off at ETMX for the same job to be done.
Bob cleaned all safety glasses in 10 % Liquinox soap in water solution first. The transmittance of glasses were checked at 100 mW 1064 nm S polarization, beam diameter 0.5 mm at 0-20 deg incident.
Coherent FieldMate power meter measured T= < 1 mW of all glasses.