Time: 2019 May 21 14:46:29
Found 2319 logbook entries, displaying most recent 100
Logbook Contents (Most Recent Entries)
17 May 2019 Friday 15:34 [Devon] The alpha source Na heater has been rebuilt and outgassed. Source making 700 nA.
30 Apr 2019 Tuesday 15:17 [Devon] Historical note: All hardware relating to belts and the belt charging system has been scrapped or trashed. No going back from pelletron.
30 Apr 2019 Tuesday 13:19 [Devon] Just noticed that there is no current on the alpha source Na heater. Most likely the heater head wire has failed which is an extensive repair and will hinge upon the viability the thermal ceramic solution which hasn't been opened in years. There's always a chance it could be an external problem with the transformer too. Won't be accessable until Thursday due to Cs source ops.
15 Apr 2019 Monday 13:08 [Tom Massey] Both the HE and LE tube valves were found closed. They had previously been opened. Transient?
12 Apr 2019 Friday 09:13 [Devon] VESDA ECO O2 detectors calibrated
03 Apr 2019 Wednesday 08:17 [Devon] 13C beam test: vacuum baked a cathode made with from the old batch of 13C and fine Ni powder. Baked at around 400C due to lack of attention. At Cs Res of 120C the source built up to an output of 8 uA after about 10 hours, leakage currents low and stable, ran all night without issue. This is a huge improvement. Also found that the LE BPM is a great aid in setting the chopper. Next step is to try a slightly higher Cs Res temp and put beam thru to the gold foil timing check device.
19 Mar 2019 Tuesday 18:40 [Tom Massey] We started at 7.0 MeV deuterons today. The Tandem Watch plot showed smooth behavior for all of the downcharge. The LE current was stable throughout and followed the column and HE down charge.
09 Mar 2019 Saturday 12:22 [Tom Massey] We had a Boy Scout group tour today. We removed the toy Van de Graff from the small target room to the lobby. A shot demostration was done with the Van de Graff. I checked and saw now reset of the radiation monitor. No alarm sounded on any panel.
21 Feb 2019 Thursday 17:37 [ingram] Alpha source extraction is not turning off.
21 Feb 2019 Thursday 08:24 [Ingram] Emergency generator being tested this morning.
15 Feb 2019 Friday 13:57 [Devon] Carbon beam tests. The 13C cathode that we had on hand for a number of years finally ran out, was producing ~7.5 uA on last use. Tried a number of new cathodes for amorphous 13C, mixed 5:1 by mass (per Middleton, basically equal volume) with -100 mesh Ni, equal volume with -125 mesh Ag, equal volume with .08-.15 micron Ni, and equal volume with graphite. In all cases beam yield was low, on the order of a microamp or less, and the source output suffered from periodic spikes in head voltage currents coupled with a crash in beam current. After each crash the beam would recover to the previous level until the next crash. The frequency of the crashes was proportional to the amount of Cs as set by the PID controller on the reservoir, the more Cs, the more frequent the crashes. Between crashes the head voltage currents had reasonable values. The graphite/13C mixture seemed to give the best beam yield at 1.5/1 uA of 12C/13C. There was also uncertainty on resolving peaks with the inflection magnet. The magnet was periodically swept to look at relative intensity of observed peaks with monitoring being done on the largest peak. Turns out that the inflection magnet calibrations on hand for all these years were not very accurate, and the monitored peaks may well have been mass 14 or 16. The Inflection magnet calibration was re-done during the graphite/13C test with 12 known-to-be-good data points which resulted in the new magnet calibration that is posted in the books. The 12C and 13C peaks were validated by analyzing the +3 beams with the accelerator. For a confirmation of source behavior, a previously used graphite cathode was loaded and operated for extended time at different Cs reservoir temperatures. No sign of the periodic crashes after operating a day, all night, and the next day. At Cs Res = 95C, 12C = 4 uA. 100C = 9 uA. 105C = 14 uA. Just for fun, got off the 14 uA 12C peak and found 200 nA of mass 13, 1.4%. Probably mostly natural 13C, maybe a little 12CH. After a few hours at 105C there began to be random ticks in the head target voltage. Maybe not surprising since this pellet had previously overwhelmed the source at 110C. The future of 13C beams is still TBD…
11 Feb 2019 Monday 16:24 [carter] A software imposed maximum current limit has been incorporated in the tweaking magnet control software to prevent the supply from going into protection mode.
05 Feb 2019 Tuesday 15:21 [carter] Found that previous solution to the 0,75 Hz periodic high frequency noise by grounding the BPO inverting transformer introduced a problem that caused the BPO amplifier to "lock out" at 60 Hz for about 1 ms every 16 ms. Now back to the inverting transformer with ground isolation and the BPO is again good.
01 Feb 2019 Friday 15:52 [carter] Replaced UPS above BPM with new APC Back-UPS Pro 1000S. When restarting control1 computer found it would not power on, replaced control1 computer power supply. Then found Planar PL1910M monitor for control1 would not power on, replaced with another Planar monitor. All seems back to normal now.
31 Jan 2019 Thursday 19:22 [DCI] UPS above the scope for the beam profile monitir was in a state of alarm. It has gone quiet again after several minutes.
29 Jan 2019 Tuesday 11:25 [Shift sign-up for next week's CMU run] Greetings Operators, Next week our friends from Central Michigan University will be back to run 40Ar(p,n) on the beam-swinger line. The plan is to run overnight from Tuesday on. Running on Saturday is unlikely, but not out of the question. Please indicated your availability and willingness to be an operator in the Doodle link below. Note that this is a collaborative run and so won't involve any bonus pay. https://doodle.com/poll/ikxcctsz78zk8cvt Thanks for pitching in! -Zach
25 Jan 2019 Friday 16:03 [Devon] 2019 Maintenance: 6007 hours. No problems inside the tank so no entry, but, 1588 hours and 2 years since last gas system maintenance. Opened the recirculator pig to find it coated with brass dust. Apparently the relief valve is operating some. The test pull handle on the seal bonnet is getting off axis and rubbing the hole in the spring tensioner cap. Wear spot indicates no appreciable axial travel, its like the bonnet is just tilting open a little on one side. Shop fabricated a Teflon bushing to try to keep the action on axis. Changed blower oil, greased motor and blower. Chain coupling was dry but not much wear on it and sprockets. Cleaned with WD40, re-installed. Scrubber cartridges serviced, all 3 sieves gained weight again, 5A by a factor of 10.7%, 4A by 9.1%, 3A by 11.2%. The idea of not going into the tank was a bust. The man door leaked badly on gas in even though it was never opened. The leak was bad enough to register on the VESDA O2 monitor in the pit and it never sealed by full tank pressure. So, entry. The chain 3 charging current lead is rock solid in the P clamp. The static chain measurements were as follows: C1= 1-7/8”, same as 1020 hours ago. C2 = 1-15/16”, also unchanged. C3 = 1”, a drop of 1/16” from 1020 hours ago. Chain 3 should have another 5/16” to go before hitting the alarm switch. With so little change in static measurement we skipped the running measurements. Meggered all resistors. Found one column resistor open, replaced. Odd that there were no signs of a bad resistor in last runs.
25 Jan 2019 Friday 12:43 [Devon] Cesium sputter source not working well with new 13C. Low yield, 1.5 uA, and unstable yield, periodic spikes in PS currents. Replenished Cs reservoir, very little left but not bone dry. Checked acc tube resistors, all good.
23 Jan 2019 Wednesday 11:20 [carter] The switches on the collimator current meter unit were cleaned with De-Oxit contact cleaner.
23 Jan 2019 Wednesday 11:19 [carter] Keithley picoammeter (beam current) meter switches cleaned and lubricated to repair difficult to rotate polarity switch. Also, replaced power supply filter capacitors in the unit.
09 Jan 2019 Wednesday 16:43 [carter] nmrgoto problem resolved, the filter capacitor in the 10 volt step pulse pull-up supply at the controller was bad causing large 60 Hz ripple on the step pulse pull up value resulting in a fraction of the step pulses being too small to step the stepping motot controller. Replaced the capacitor and now using the original nmrgoto command values with good results.
08 Jan 2019 Tuesday 15:47 [Devon] Pelletron hour meter reading 1/8/2019: 6007. Accelerator operating hours in 2018: 846.
02 Jan 2019 Wednesday 15:02 [Carter] Operators... Please remember to turn off the Ludlum dosimeter when shutting down the accelerator to conserve the batteries.
02 Jan 2019 Wednesday 11:45 [carter/jacobs] Quarterly alarm and shutdown tests complete for January 2019 by Carter/Jacobs. Modified the email section of the reminder program to reflect the recent domain change from ohiou.edu to ohio.edu so email reminders and acknowledge should work properly next quarter.
02 Jan 2019 Wednesday 11:14 [carter/jacobs] Tritium monitor repair, new diaphram, oil bearings and new air inlet filter.
23 Dec 2018 Sunday 09:21 [Devon] The tritium monitor pump was violently noisy. Turned the monitor off until we can work on it.
22 Dec 2018 Saturday 18:15 [Ingram] Power came back at 6:00 PM after second outage. I have switched the nitrogen bottle on the Keck system for a new one. I was doing that when the power came back on. That was the last full nitrogen bottle, we need to order one.
21 Dec 2018 Friday 16:53 [carter] The swinger BPO noise (high frequency RF at ~0.75 Hz repeating) nearly completely removed by removing the ground isolation feature of the inverting transformer used in the BPO circuit.
12 Dec 2018 Wednesday 13:22 [Devon] FM finally here to look at down chiller. (control cabinet had blown open on stormy, windy day. Got wet, shut down). They cleared the errors and re-started. Chiller appears to be undamaged.
06 Dec 2018 Thursday 11:09 [carter] The NMR command "nmrgoto" was missing its target so a "fudge" factor has been included in the command calculation to help get closer to the desired frequency. Diagnostics are continuing but a convenient workaround program named "nmrto" has been created that works the same as the mnrgoto command (enter a floating poingt frequency in MHz. for example "nmrto 8.627866") but will make multiple attempts to get close to the entered frequency and seems to work well, even better than before.
05 Dec 2018 Wednesday 08:04 [Ingram] Source camera not responding to movement controls, blue buttons.
01 Dec 2018 Saturday 11:37 [KB/RG] The E1 water and vacuum systems/phase failure detected alarm was going off a few minutes ago. Rekam and I (Kristyn) have acknowledged the alarm and checked to see if vacuum remained. We still have vacuum, so no further action is required.
26 Nov 2018 Monday 15:12 [Shift schedule for this week] Greetings Operators, Thanks for signing up for shifts this week. The resultant schedule is here: https://docs.google.com/spreadsheets/d/1IgQk3vepSmgd_0yMm9pDD1FSWhcT2CjqdMoR_9_W3vU/edit?usp=sharing -Zach
26 Nov 2018 Monday 13:40 [Shift sign-up for this week's ORNL run] Greetings Operators, Please fill-out the following Doodle poll if you can be an operator for this week's experiment: https://doodle.com/poll/kghxz8t728n88znt. As usual, we'll wind-up having one operator from 8-4 and two otherwise. I'm not sure if we'll be able to have overnight operation or not, but it would be good to know if this is possible. Just as a heads-up, this is a collaborative beam time [i.e. is intended to lead to a paper] so it isn't paid extra. Apologies for the late notice and thanks for your participation! -Zach
16 Nov 2018 Friday 11:32 [carter/Brandenburg] CMU experiment finished. 1.5 hours after the sputter source heaters were run down and temperatures had stabalized and were at shutdown temperatures, the Target Current had leveled off to 5 ma and was not falling. Target Current remaind at 5 ma for nearly an hour then source power supplies were shut down anyway.
06 Nov 2018 Tuesday 07:40 [Devon] VESDA: calibrated ECO O2 sensors
05 Nov 2018 Monday 15:31 [Availability for CMU experiment (doodle poll)] Greetings Operators, Next week, Tuesday November 13 - Friday November 16, George Perdikakis and Panos Gastis will be visiting the accelerator lab to run 40Ar(p,n). They are interested in running overnight, if we can manage. Please fill-out this Doodle poll within the next day or two so that I can look into setting up a schedule for the experiment. If you are only Operator 1 trained, please indicate this with a comment below the poll. Poll: https://doodle.com/poll/5vkvg8pn3i4qerk4 Thanks for your help. -Zach
05 Nov 2018 Monday 14:33 [Devon] A proton beam and Don will be available tomorrow, Tuesday, 11/6, after 10:00, for pulsing and bunching training and/or review. NMR training may also be a possibility if time permits. Those of you operators that need these skills should try to stop by. You can view your training status at: https://edwards2.phy.ohiou.edu/~oual/operators/operators.php
01 Nov 2018 Thursday 11:16 [carter] Test message in logbook
23 Oct 2018 Tuesday 15:23 [Devon] Process chiller is back in business. It was the tee fitting that sprung a leak. The flare on the fan differential switch capillary was fine. FM pumped all the gas out of the circuit to remove the tee, but on removal it was discovered that the port on the coil manifold has a Schrader valve. Any time we have trouble with fan diff switches we don't need to worry about removing gas from the circuit because the tees are on Schrader valves. The gas was put back in the circuit and we observed low pressure cycling at start up but then successful running. When the second circuit started and both fans ran the small circuit suffered low pressure cutouts. Both cases expected for low gas charge due to leak off. Added more gas to the small circuit and everything is working fine. Ambient temp was 62 today.
17 Oct 2018 Wednesday 08:18 [Devon] Sputter source: Cleaned. Tap hole for top bolt on target shroud stripped on first few threads, longer bolt with nut as spacer used. Airlock bolt at target power lead not threading well, may be time to replace lexan section. Cs oven re-used.
12 Oct 2018 Friday 14:05 [Yenuel Jones-Alberty] Completed Operator 2.
01 Oct 2018 Monday 11:45 [Devon] Process chiller update: small circuit ran with normal behavior most of the weekend, there was some short cycling during the peak heat of the days. It was running happily first thing Monday, I set the low pressure cutout back up to where it should be for 34F at the HX baffles. By 10am it was ambient warm enough to cause low pressure cutouts. Found the leak in the circuit, its at a small tee where the fan differential pressure switch ties in. I need some shop Doug consultation before laying wrench on it, may be wise to use the compressor to pump Freon into safe storage before taking a chance on breaking something. The small circuit is disabled for the time being. The middle and large circuits will handle our loads. The fan differential switch on the large circuit chattered at first use again (previous log story), seemed to settle down and hold contact after a short time.
27 Sep 2018 Thursday 14:35 [Devon] I heard rapid fan cycling on the process chiller. On investigation, Looks like circuit 3 (small) was having low pressure issues. Pressure driven fan cycling rapidly, compressor cutting out during runs. Lowered the low pressure cut out by around 10 psi and performance seems to have stabilized. Need to arrange for FM to come add some 404A next week.
21 Sep 2018 Friday 15:33 [Irin Sultana] Passed Operator 2
14 Sep 2018 Friday 11:57 [Tom Massey] The target current became large overnight. It reached 20 mA causing the high voltge supply to regulate on current instead of voltage. The beam current was unstable and lost at times. Devon suggested turning the Cs resevoir down for a time and turning down the target voltage. After ~15 minutes the target voltage was returned to the normal setting (just past 6). The target current was less than 10 mA. The Cs reservoir was turned back to 0.310 A after the target current dropped below 5 mA. The beam has been stable since then.
20 Aug 2018 Monday 16:16 [Devon] Charging problem on chain 3 was the current lead wire again. Ring terminal fatigued and broke. This time a P clamp was used to anchor the thick insulation to the brush post prior to the ring terminal connection. Not sure why the failure gave us stable behavior this time. Maybe we were looking at it in control this time, and last time we were looking at it un-controlled.
17 Aug 2018 Friday 13:43 [carter] Fan in the NMR frequency counter primary Agilent 53131A went bad. Repaired with new fan and power supply.
14 Aug 2018 Tuesday 16:11 [Devon] The charging system trouble that developed last week is not in the metering system. The metering has been tested extensively and is working fine. The problem, whatever it is, lies inside the tank. These symptoms are not like anything we have seen before. Gas out Thursday. The status of the run next week depends on what we find on tank entry Friday.
09 Aug 2018 Thursday 12:07 [Devon] After the accelerator was re-started this morning we noticed multiple indications that chain 3 was not charging. This condition developed yesterday evening. Upon further analysis other indications show that chain 3 is in fact still connected and charging properly. We are working on the assumption that something has failed in the chain 3 current metering circuit. We will continue to run. For the remainder of the run we need to monitor various parameters to ensure nothing gets worse. The blue line (upcharge-downcharge) on the "crontab" display on control2 computer should be roughly the same value as the upcharge on chain 1 or 2 on the TPS. The downcharges (red, green, and black lines on "crontab") should be smooth and constant lines at any given terminal voltage. We will review the value of the "crontab" display at the next TALC meeting.
08 Aug 2018 Wednesday 21:39 [T. Massey] The logging for the sputter source is no longer working. The values for the parameters are all zero on the plots both on the web and local versions.
26 Jul 2018 Thursday 15:08 [Brit Kenady ] Finished Operator 2 training.
25 Jul 2018 Wednesday 15:22 [DCI] Regulated air line pressure rasied to 94 psi in mechanical room, 85 psi on panel over control panel. The analyzer and HE cups are now moving out completely. The analyzer cup is moving a lot faster too.
24 Jul 2018 Tuesday 10:55 [carter] Replaced defective f/n selecor switch in chopper/buncher drive and phasing panel. Functioning properly again.
23 Jul 2018 Monday 09:26 [Thomas N. Massey] Quarterly tests were completed on July 17, 2018 by Devon Jacobs, Don Carter and Thomas Massey.
17 Jul 2018 Tuesday 16:51 [Tom Massey] We had a 80% warning today . This is believed to be due to the Small Target Room door not being closed enough to trip the interlock. No exposure was given. Everyone was in the Control Room when it happened. The Radiation System was reset to remove the accumulated dose and prevent an unneeded shutdown. The accelerator tubes were conditioned up to 4.43 MV. Beam was run at 4.326 MV. Over 10 microamperes at LE cup, 4 microampere on the HE cup and 1 microampere on target. More current was available but the OSU students wanted to keep the measurements stable.
12 Jul 2018 Thursday 10:52 [carter] Previous maintenance on the NMR (12 Jan 2018) required that the calibration values needed to be modified to provide proper operation of the nmrgoto command. Today it was found that tne nmrgoto command was overshooting the value where previously it had been undershooting the requested value. The original calibration values were restored in the nmrgoto.daq file and the operation is now quite good. Not sure of the cause, slipping belt that is now not slipping? Anyway, nmrgoto now is quite close.
10 Jul 2018 Tuesday 17:20 [DCI] 5:00 PM Accidental radiation shutdown. Tom said the vault gate must of boounced and not latched. He removed the LE cup and the shutdown occured. No one was exposed.
29 Jun 2018 Friday 19:16 [Devon] The swinger turbo ion gauge controller failed sometime during the runs friday. It won't light up either filament. I shut down the turbo pump so there won't be any confusion about vacuum status.
27 Jun 2018 Wednesday 13:06 [Devon] Power came back around 05:30. All systems back in operation and the run has resumed as of 13:00
27 Jun 2018 Wednesday 03:27 [Justin] Power failure at EAL is still ongoing at this time.
27 Jun 2018 Wednesday 02:03 [Justin] Power failure to EAL at approximately 01:42. As of 01:52, the power outage persists and the door to the small target room is closed with no ability to access the equipment in the vault area. Returned charging voltage, terminal voltage, and gain to default settings.
26 Jun 2018 Tuesday 14:34 [carter] Test of new all operators email list
26 Jun 2018 Tuesday 13:40 [devon] test
26 Jun 2018 Tuesday 09:40 [carter] Repair 400 Volt chopper power supply (shorted rectifier, also replaced 47 uF 450 V electrolytic capitors)
26 Jun 2018 Tuesday 09:38 [carter] 2Y LE steerer was unstable. Removed the rack panel of 2Y, 1Y and 2X steerer supplies. Found all (6) 7239 vacuum tubes weak and replaced. Replaced open 2 Meg HV resistor in the original 2X supply. Also replaced 50 uF 50 V electrolytic capacitors in each supply. All 3 supplies now repaired and seem stable again.
19 Jun 2018 Tuesday 09:55 [Zach] Greetings Operators, As discussed at last week's TALC meeting, we will have visitors from LLNL next week (June 25- July 1) who will need operators to assist them and will pay for this assistance. Please express your interest to participate in various shifts during the experiment using the following Doodle poll: https://doodle.com/poll/d7n22ssrfai9vtpb. Ultimately two shifters (one operator 2 trained and one warm body) will be required for the 0-8 and 4-Midnight shifts. Only one operator 2 trained individual will be required for the 8-4pm shift (except on the weekend, where 2 will be necessary). Prompt replies would be appreciated so that we can get the schedule set well ahead of time. -Zach
12 Jun 2018 Tuesday 15:35 [carter] LE 2X steerer supply was found not functioning properly. There was an identical supply that was originally used for the 1Y steerer (removed to install the LE BPM) and this supply has been connected to control the 2X steerer. The supplies are relabelled accordingly.
31 May 2018 Thursday 08:05 [Devon] Sputter source cesium reservoir bone dry. Cs replenished. Source on.
18 May 2018 Friday 12:04 [Devon] Training for swinger endorsement and familiarization attended by: Brune, Meisel, Massey, Carter, Jacobs, Voinov, Doug Soltesz, Shiv Subedi, Tyler Danley, Rekam Giri, Kristyn Brandenburg, Som Paneru, and Justin Warren.
17 May 2018 Thursday 10:23 [carter] Test of logbook
04 May 2018 Friday 11:46 [Devon] Beam testing: A problem was observed in the 15L RBS chamber. The beam current and vanishing points were asymmetric about the optical centerline as the beam was steered left or right with the switching magnet (current max was not in the center, beam vanished at different distances from the center). This behavior indicated that the beam was not traveling down the 15L line on axis. We considered that the was some obstruction between the switcher and the collimators near the chamber, perhaps a failure of the fixed collimator on the exit port of the switcher. As a check and confirmation we ran the beam down the 30L line expecting to see symmetric behavior about the optical center, but instead, found the same asymmetric behavior, beam not traveling down the line on axis. The hunt then moved further upstream with the assumption that beam was leaving the switcher off-axis because it was entering the switcher off-axis. We monitored current on the collimator that protects the BPO on the analyzer leg - this is normally never looked at. Found that beam was striking the collimator in the current state of tuning, off center in the x-axis. With slight adjustments of Q1 and steering we found that the current on the BPO collimator could be eliminated (all beam thru the hole). With minimizing current on the BPO collimator the behavior of the beam in the 30L line became symmetric. Beam was switched back to 15L and symmetric behavior was again observed. Keeping current off the collimator proved to be a valuable tuning aide. The plan is to permanently monitor the BPO collimator current as a tuning aide going forward once a suitable meter is decided on.
03 May 2018 Thursday 18:10 [carter] Repaired sputter source 24VDC power supply used in HV interlock circuit (station W). Source HV interlock system seems to be working again.
24 Apr 2018 Tuesday 11:17 [carter] Our network firewall software has been upgraded to the current version and installed on a new hard drive. If you notice any issues with the new system, let me know.
12 Apr 2018 Thursday 16:55 [carter] The beam current meter on the console position 5 has been connected to the EG&G CD1010 current integrator thru a 1 meg ohm resistor. Full scale on the CD1010 will give 1 uA on the console meter position 5. Should connect to the CD1010 monitor output or filter output for a smoother indication.
11 Apr 2018 Wednesday 17:22 [carter] The helium source heater current meter was unstable and has been replaced with a new meter. The old meter had been calibrated to read (heater current / 2) and the new meter will read the actual current in the heater. Temporary calibration currents for the new meter for operating current and standby current are posted on a note located near the meter. When the values are finalized, a new permanent note will be posted.
05 Apr 2018 Thursday 08:10 [Devon] Source cooling water was down to the alarm level. Added water to loop. Alarm light did not clear to off. Tweaked the pot on the sensor power, alarm light cleared.
22 Mar 2018 Thursday 08:24 [Devon] 15L chamber ion gauge developed a leak at one of the filament/grid feedthrus. Replaced.
21 Mar 2018 Wednesday 10:38 [carter/jacobs] Alpha source 24 volt control and TC gauge supply had bad filter cap. Was reading only 20 volts with 4 volts ripple. Capacitor replaced and output voltage restored to 26 volts when in circuit and loaded. Symptom was high reading of filament vacuum on alpha source.
19 Mar 2018 Monday 16:46 [Devon] Alpha source cleaned. Replaced filament vacuum TC gauge.
15 Mar 2018 Thursday 11:03 [carter] Analyzing magnet would not run down. Found Q6 mounting screws (collector connection) had become loose. Tightned and all OK again. May have been cause of intermittend analyzer magnet instability seen once in previous run.
14 Mar 2018 Wednesday 15:40 [carter] In an effort to add stability back to the slit control mode of the TPS, the following adjustment parameters were restored to the factory default values for the slit control system. R6, slit gain modified from 5.0 to 3.1. R12, slit/cpo gain modified from 8.0 to 5.1. R13, slit/cpo crossover frequency modified from 5.0 to 5.8. These adjustments will lower the gain of the slit control system and increase the 3db slit low pass from 8hz to 10hz. Hopefully will restore some stability in slit operation. Some beam/focus combinations were causing oscillations in the control system and required running the control gain at quite low values for stable slit operation.
20 Feb 2018 Tuesday 10:51 [Devon] The current meter/feed wire to chain 3 was laying on the floor. Blue gauge crimp-on ring connector fatigued and broke. Don replaced it with a yellow gauge ring connector, heavier construction. The door is sealed. Gas in Wednesday.
16 Feb 2018 Friday 12:15 [Devon] We lost telemetry from chain 3 during the run today. The terminal dropped some and was unstable. The experiment has been suspended. Gas out Monday.
29 Jan 2018 Monday 11:37 [RSO] accumulated shut down was experienced due to excessive time needed to complete annual calibrations of fixed monitoring system and two hand held neutron detectors
23 Jan 2018 Tuesday 15:41 [Devon] Comfort chiller woes...chiller quit working over winter break, touch screen controls fried preventing operation. FM went ahead and replaced old water pump while chiller was down. Dry loop and cold weather during pump change liberated a great deal of rust in the pipes. Trane replaced the controls but chiller kept shutting down due to poor flow, rust plugged strainer screens, 3.8A on pump motor. Flushed and cleaned screens a number of times, pump flow improved, 4.4A on motor, chiller running. Measured 120-140 gpm with sonic flow meter while air bubbles were circulating. Coils on chiller cleaned. Will continue to monitor motor amps and flush strainers for a few days.
19 Jan 2018 Friday 15:56 [Shiv Subedi] I passed the operator 2 certification with flying colors. :)
12 Jan 2018 Friday 16:14 [Carter] NMR head maintenance. Replaced weak tubes V01 (6922) V02,03 (7788). V04, 05 (5751) OK. Replaced electrolytic capacitors in RF head and stepping motor controller. Also replaced stepping motor because of intermittent lock-up of shaft. Found gears worn and in need of new lubrication. New stepping motor installed. Added correction factors for nmrgoto up and down to restore calibration. Now have very nice NMR signal with original amplitude and symmetry restored. Also lower noise level.
09 Jan 2018 Tuesday 12:21 [Devon] Process chiller loop #1 problem traced back to the pressure switch that controls the fan. Contacts had developed corrosion since it doesn't get used much. Sprayed with LPS lubricant and exorcised the mechanical settings. Fan contactor working smoothly after 2 run cycles.
08 Jan 2018 Monday 10:55 [Devon] I transposed the numbers 3 and 1 in the previous post. #1 is the big circuit, #3 is the small circuit.
07 Jan 2018 Sunday 14:36 [Devon] The process chiller got too cold to run Saturday night. As it warmed up Sunday morning there was some odd behavior, it kept trying to use the big circuit, #3, over and over. I found the #3 pressure driven fan contactor trying to engage and chattering, fan was starting and stopping. I suspect compressor #3 was shutting down on high pressure due to the lack of a fan and never reaching its set point, but, keeping the water below the activation temperature for loops #1 and #2. I've disabled loop #3 and loop #1 has resumed functioning, assume #2 will function if called. Need to investigate the #3 fan contactor and pressure switch this week. And the ACPC CB3 tripped on activation again.
02 Jan 2018 Tuesday 09:44 [Devon] The week before Christmas break we successfully installed new CTI cryopumps and compressor on the HE end of the vault, and replaced the LE tube gate valve.
02 Jan 2018 Tuesday 09:19 [Devon] Pelletron hour meter reading 1/2/2018: 5161. Accelerator operating hours in 2017: 742.
22 Dec 2017 Friday 14:49 [DCI] Pressure between switcher and analyser fallen to 7E-6. If I open to 15degL it falls to 6E-6. Pressure in 15degL rose from 8E-7 to 1.6E-6. If there is a leak from the 45degR it is small.
26 Nov 2017 Sunday 15:24 [Shiv Subedi] Alarm was on for the 'phase failure' in the E1 console and the 'Tritium monitor'. I pressed the 'ack' button in the E1 console and reset button in the tritium monitor. Both of the alarms then went off.
06 Nov 2017 Monday 13:48 [Devon] We are declaring victory on the process chilled water main loo pump. Everything is back to normal with an up-sized motor. A more detailed write up is available in the logbook.
06 Nov 2017 Monday 13:47 [Devon] The 1 hp motor on the process chilled water main loop pump failed spontaneously on a Sunday at 5 pm. Didn’t realize it until Tuesday afternoon when it was noticed the chiller was not running. The alarm threshold was set just below the temperature reached during city water dump cooling. The dump valve opened automatically at a loop temp of 56F and maintained the vacuum systems. The pump bearing assembly had run dry on its oil bath lubrication and the extra drag likely contributed the motor failure. Proceeded to order a replacement 1 hp motor and installed it, also added oil to bearing assembly. The motor was sluggish to start but then ran. Kept an eye on it and found the motor body was 200F after half hour of operation. Shut it down and began to work on replacing the bearing assembly. However, found that the existing bearing assembly and the new one both had basically the same amount of drag when turned by hand. Some, but not much, drag. Put the new motor back on and measured current draw. The new motor was spec’d for 115/230 V, we have 208V. Normal full load at 230V rating is 4.4Amps. We extrapolate that this would be 4.9A at 208V. We measured 5.5A at 208V. Got a transformer to provide 230V and measured 4.6 A at full flow. This motor is working at its 1.15 safety factor limit. The flow in the loop was reduced by partially closing a valve until the current draw by the motor was just below the normal full load reading. In the mean time we used the measured current draw at full loop flow to determine that full flow required 1.3 hp. Ordered a 1.5 hp motor. The bigger motor has been installed and the loop is now flowing at full flow again, motor is drawing 7.5 Amps. 1.3hp/1.5hp = 87%. Rated full load current at 208V is 8.4 A. 7.5A/8.4A = 89%. The full flow load in this loop would appear to be 1.3 hp, too much for the old motor, but not working the new motor too hard.
02 Nov 2017 Thursday 14:00 [Devon] Process chilled water update. A new motor was ordered and installed. The old motor was repaired and works again too. The new motor ran the pump but motor and bearing housing became quite warm after 1/2 hour of operation. Motor is shut off and pump disassembly is underway to replace the bearing assembly.
02 Nov 2017 Thursday 07:23 [DCI] The high water temp/air alarm was sounding this morning and Janitor reported to the police, who called me in. I have disconnected the alarm and reset it. David Ingram
31 Oct 2017 Tuesday 16:53 [Devon] The process chilled water main loop pump quit running sometime this morning. There were no alarms due to...long story. Initial investigation seems like a motor failure. More diagnostics in the morning. We are dumping city water to cool vacuum systems. No magnets, no running until its repaired.