| date yymmdd |
td | description | |
| 200228 |
enc |
found that i had overwritten the limit
switch,encoder page with tdfailure log (probably sometime
before 2018) brought old td.html page that had some limit switch, encoder info before i made the limitswitch/encoder page. |
|
| 200228 |
4 |
td 4 jack fails. replaced on 200303 |
|
| 191126 |
8 |
load cell 1 td 8 dropouts were a loose cable
in the hoffman box up the signal conditioning or a/d board. |
|
| 180629 |
8 |
little star replaced, dac board replaced. |
|
| 171115 |
8 |
replaced cable ldcell td8-2 (broken during
maria). td8-1 still won't balance the -200mv offset. set
values to always read 0. |
|
| 170901 |
8 |
td 8 jack replaced |
|
| 170829 |
4 |
td 4 ldcell 4-2 fails |
|
| 170827 |
12 |
td 12 replaced |
|
| 170825 |
4 12 |
td 4 replaced.. it had locked up..(more info) started to hear noises in 12.. looks like it has a problem with a bearing. |
|
| 1606xx |
12 |
load cell 12-1 fails after 1606 hf run. |
|
| 160317 |
8 |
new load cell connected 8-2.. need full
calibration after painting done (and we can move the az,
dome). |
|
| 160113 |
8 |
finally tried to recalibrate load cell td8-2
wouldn't balance. looks like the arcing back on 151110
damaged the load cell. It will be replaced. |
|
| 151110 |
8 |
cable for load cell td8-2 had arcing through
outer protective sleeve (close to yoke). this was during the
hf run. cable eventually replaced |
|
| 150914 |
4 |
watch dog time was releasing for a few
seconds every now and then, and then running ok don't know whether it was watchdog timer or little start. replaced watchdog timer For debugging:
|
|
| 140923 |
12,8 |
lightning strike damaged td
12,td8 td12 came back on line later that afternoon (replaced little star) td8 remained offline till .. 28sep14.. trouble with 485 communications. we manually moved td8 to 12.5 inches on 26sep14 so platform closer to focus at night. |
|
| 130302 |
4 |
tiedown 4
position jumps to 24 inches, stays there awhile, then
jumps back. |
|
| 120702 |
4 |
changed motor on td 4. |
|
| 120516 |
8 |
felipe soberal writes: During the inspection and lubrication process performed at Platform Tie Down #8 last Monday, it was identified that we also have a worn ball screw on the actuator jack. Approximately three tooth on the lower end of the screw when the jack is fully extended were found broken. This jack has been in service since June 2, 2005. |
|
| 120423 |
12 |
jack replaced. |
|
| 120419 |
12 |
td12
stops with foldback, cmdspderr errors. Td12 jack
making loud noises when pulling down. Torque measured in
td12 much larger than the other tiedowns, for similar kips. Ended up having to replace the jack. |
|
| 120418 |
12 |
one of the new little stars
(from the large order) installed in td 12 for testing. |
|
| 120227 |
8 |
recalibrated td 8 load cell.
|
|
| 120225 |
12,4,8 |
|
|
| 120222 |
12,4,8 |
|
|
| 120219 |
4,8 |
change of 120217 did not fix
the drifting of td4 clock. at 10:42 on 120219 i switched the order that the vxWorks program talks to td4,td8 before : td12,td4,td8 now : td12,td8,td4 see if the time drifts switches to dt8...(120220... drift remained at td4). |
|
| 120217 |
4 |
updated software to declare
tmscounter tmscounteratlast tick to be atomic accesses
(updated in the afternoon) |
|
| 120209 |
12,4,8 |
Have been getting cmdspdErr
after switching to the new operating system. (cmdVel -
motorSpd > 50 cnts). -Measured a/d for spdMon in lab. 46.8K resistor way to big to map 8 volts to 2.5 volts. - switched 46.8K resistor to 22k got closer to correct value but still got error. -Looking back in old data, this difference was much greater than with the 22K resistor. but the general status bit saying cmdSpdErr was never set in the data read back from the little star. - There must have been a bug in the previous version of the software so that the status bit was not getting set. The new compiler fixed it? - The rp4 resistors being removed on the adc boards got rid of the abilitiy to have a reliable voltage divider. |
|
| 120208 |
4,8 |
switched little stars to see
if td4 running fast stays at 4 or moves to 8. (problem remained at 4) |
|
| 120124 |
12,4,8 |
2 new little stars installed
in td4,8, all 3 little stars now running program compiled
with version 6. of dynamic C. |
|
| 111108 |
4,8 |
td 4,8 little stars offline..
for rest of the year. |
|
| 111031 |
4 |
changed dac signal
conditioning board to see if this helps the problem from
27,29oct11. |
|
| 111029 |
4 |
tiedown 4 made load noises again at 5:21 am. | |
| 111027 |
4 |
tiedown 4 made loud noise at 1:17 am | |
| 11713 |
12,8,4 |
went offline 14:16 13jul11. td12 encoder reading bad 4,8 no communication. 4,8 remain offline for a few weeks. |
|
| 110609 |
12,8 |
recalibrated load cells 12,8.
td12-2 had one of the loadcell cables going into the amp
pulled out. measured the impedances between legs of the loadcell bridge for td12,td8. Load cells look ok. |
|
| 110602 repaired 110606 |
8 |
lightning strike.
|
|
| 110425 |
12 |
recalibrated td12 load cells. ldcell1 : was pretty close.. updated balance and gain. ldcell2: dc offset of -.237 volts. adjusted balance and only got -.118 mv left it this way... didn't modify the gain. |
|
| 101014 |
12 |
td was oscillating. replaced
encoder and started to work ok. |
|
| 100919 |
12 |
td 12 position has been
jumping to 24 inches a lot. replaced cable bus to encoder
board on 17sep10. But problem persisted. Today replaced
encoder interface board. |
|
| 100911 |
12,8 |
recalibrated load cells. td8
AtoD board still had R8 resistor in (i cut it). |
|
| 100823 |
4 |
load cells adjusted now ok,
cut R8 resistor on A/D and adjusted amps. 20aug10 adusted but a/d board still had resistor R8 in . Still need to work on Td12, td8. |
|
| 100813 |
12,4,8 |
lightening damages all 3: td12: dac, encoder board td4: little star, dac,adc, 24 volt supply td8: little star, DI1, and probably more. tensions are suspect... |
|
| 100326 |
4 |
replaced amplifier on td4.
Was giving motor output fault. |
|
| 100203 |
12 |
found broken beam where td 12
backstays connect to platform (left side looking from
north). Not sure when it broke. |
|
| 090919 |
12 |
load cell 12-2 failed. replaced with new load cell 06oct09 | |
| 090204 |
12 |
readjusted the aluminum plate
that holds the limit switches. It had been mounted about 2.5
inches off when the jack was replaced. We had no lower
limits (0 inches) since the jack replacement. limits are now
ok. |
|
| 090109 |
12 |
replaced jack td 12 |
|
| 080623 |
12 |
load cell 2 replaced with
spare that had come back from being calibrated. |
|
| 080619 |
4 |
transmission replaced. loadcell
recalibrated. |
|
| 080616 |
12 |
Found that load cell
amplifier was causing trouble with 5 volts supply. After
disconnecting amplifier the analog inputs read ok and the
encoder stopped jumping. |
|
| 080608 |
12 |
encoder card on td 12 blown
out by lightning. |
|
| 080529 |
4 |
replaced jack on tiedown 4. |
|
| 080407 |
8 |
td 8 stopped moving
at 19.57. commanded velocity remained 0. |
|
| 080407 |
12,4,8 |
the torque
readback has occasional level shifts of up to 55 a/d
counts. |
|
| 080312 |
12,4,8 |
recalibrated all 3 load
cells. td 12 now has hectors amp adjustement board (it was
the last to not have it). |
|
| 080228 |
12 |
replaced transmission. Had a loud knocking
noise ... |
|
| 071011 |
- |
after 2nd set of az swings
updated the reference position to be: 15.0718,15.3196,15.0926 |
|
| 071010 |
- |
updated the tiedown reference
position. After azswing updated the reference position to be 15.1140,15.2028,15.1670 |
|
| 071209 |
4,8 |
moved the nuts on td4 down .5
inches, td8 nut up 3.25 inches to equalize the tiedown
extensions. |
|
| 071004 |
12 |
motor faults. replaced motor. |
|
| 070328 | 4,8 | New amplifiers with hector's calibration boards installed on ldcells. Recalibrated ld cells. | |
| 070206 | 4 | ldcells recalibrated | |
| 061114 | 12 | ldcell 1 replaced. all load cells recalibrated | |
| 061111 | 12 | ldcell 1 has bad resistance on 1 of the legs of the wheatstone bridge. ldcell2 is driving both inputs now. | |
| 061108 | 12 | recalibrated both load cells. load cell 1 had water in the cover at the load cell. | |
| 061101 | 4,8 | recalibrated load cells. | |
| 061028 | 12 | replaced ldcell2 amplifier that was blown out on 061014. | |
| 061014 | 8 12 |
lightning strike blew out td8. Had to change little star,
some of the i/o boards, and some of the analog signal
conditioning boards. td12 blew out ldcell2 amplifier. This is one of the new amplifiers. |
|
| 060908 | 12 | new online ups installed in td 12. | |
| 060831 | 12 | forgot to swap the pots when the amps were swapped yesterday. corrected at 9:00 am | |
| 060830 | 12 | load cell cable before the amplifiers back to normal order. ldc1-> output ldc1 now. | |
| 060824 | 12 | load cell cables at load cell put back to normal order load Cell cable before amplifiers switched. ( in the morning). |
|
| 060823 | 12 | switched the load cell cables as they leave the load cells. | |
| 060822 | 12 | cleaned the load cell cables where they connect to the load cells. They were pretty dirty (full of corrosion) | |
| 060814 | 12 | swapped td12 ldcells back to normal position. They had been crossed at the analog input since 060719. Soldcell1 is again ldcell 1. Found the jumping problem was the db25 connector at box. Cleaning this fixed it. This td has no filters. | |
| 060812 | 12 | td12 encoder reading failed around noon after a power dip.
The encoder always read 9 inches and did not report an
error. When requested to move to a higher or lower position
(than 9 ") the tiedown would move until it hit the limit
switch (since it was looking at the encoder to see when it
got there). I manually moved td 12 to 12" using the tape
measure. I moved the other two tiedowns to the correct
position when td 12 is at 12". This position is close to
where the tiedowns were the previous nite. I checked the voltage on the encoder board and it was ok (5 volts). On 060814 the problem had fixed itself. |
|
| 060719 | 12 | swapped td load cell inputs to a/d signal conditioning board to see if problem with ldcell 1 jumps to load cell 2. | |
| 060628 | 12 | td 12 ldcell 1 started to fail on 28jun06. jumped to 40 kips and then back. Remained bad thru at least 17jul06 (date of this entry). | |
| 060612 | 8 12,4,8 |
td 8 ldcell #1 amp changed. load cells recalibrated. td 12 ld cell 2 amplifier switched to new amplifier |
|
| 060526 | 12 | analog output values wrong (velocity feedback not eq
to requested). Replaced analog output signal conditioning
brd. The same problem occurred for a short thime on
21may06. The zero vel offset for the dacs jumped back up to 2016. There is something funny going on when we replace the analog output board for td12. The offset either sits around 2020 or 2000. Are we mixing the old and new boards when we replace them ??? see /home/phil/vw/datatk/pnt/ttt/tie/tieParms.log (at the bottom) for the history of the offsets. |
|
| 060426 | 12 | analog output board fails. replaced. | |
| 060420 | 12 | digital i/o output was causing the master contactor to not close reliably (more info) | |
| 060306 | 12 | encoder replaced. Also noted that the cable that encoder plugged into may have been dirty . cleaned with water displacer. | |
| 060303 | 12 | replaced encoder interface board. | |
| 060302 | 12 | td12 releases because of bad enc reading. | |
| 051027 | all | installed db25 connector filters for load cell inputs and pcu . | |
| 051026 | td12 | replaced analog output board and analog output signal condioning board. | |
| 051014 | td4 | replaced amplifier. It went bad about a week ago. Recalibrated amp1 , amp2 of td4 | |
| 050916 | td8 | the analog inputs from td 8 had trouble during the morning of 16sep05. The plots show all of the analog inputs vs time for the morning of 16sep05 (.ps) (.pdf) (black td12,red td4,green td8). The first 6 (+24volts, -24volts, brake24volts, ldcell1, ldcell2, and encoder 5 volts all jumped together. At 2:50 they jumped to the maxium value for a few minutes. From 3:30 to 4:00 and again at 6:10 they where at the maximum value. The velocity feedback and master amp speed monitor did not have this problem (the short spikes they have is rfi in the cabinet). The master amp current looks like it jumped up at 2:50 but not at the later times. Need to find out what these inputs have in common. | |
| 050914 | td4 | Load cells out of calibration (again). ldcell1 amp had dc offset of 1.5 volts. Both load cells had small oscillations in the output (with no input load). Replaced both load cell amplifiers. | |
| 050904 | td12 | db25 filter for pcu cable shorted out 24 volt supply. removed filter. | |
| 050902 | td8 | both ldcell amplifiers 8-1, 8-2 had their excitation
voltage at 0. replaced both load cell amplifiers then
recalibrated. This had happened a while back (probably on
25aug05. removed the db25 filter for loadcell 8-1. it was bad (need to send away for more filters). |
|
| 050902 | td4 | both load cell amplifiers have excitation voltage of 0. need to be fixed.. | |
| 050825 | td8 | lightning.. replaced little star | |
| 050825 | td12 | lightning .. replaced encoder interface board, signal conditioning for dac, analog input fuse for input 3? | |
| 050728 | td12 | trouble with td 12. replaced little star. releasing. | |
| 050625 | td12 | lightning trouble. See writeup. Ended up replacing little start, amp. | |
| 050317 | td12 | replaced jack td 12. looked at prelim encoder position. moved by about .2 inches. | |
| 050317 | td12 | replaced encoder board on td12. The encoder value had jumped from 13 to 24 inches at around 9am. | |
| 050225 | td4 | td 4 jack breaks. looks like bad ball bearing. replaced jack 28feb05. reset limit switches, encoder. | |
| 050131 | td12 | changed filter ldcell1,2. then the values were fine. Must have been water in the filter. | |
| 050126 | td12 | td12 ldcell 2 value value jumped to a lower reading. this means that both load cells are reading low. | |
| 050124 | ts12 | td12 ldcel 1 dropped about 10kips in 45 minutes. | |
| 050117 | td4 | replaced filter on ldc1
cable. it was bad.. recalibrated all ldcells for the 3 tiedowns |
|
| 041116 | td4 | still trouble with td 4. occasionally when command from
stop, td 4 would 1.release the brakes 2. wait a few seconds 3. go max speed.. this caused and overspeed fault . replaced amplifier. Still had trouble. replaced a number of little stars, had trouble with parameters. Loaded ok but when we cycled power on LS, they went back to the original values. CB2,3 tripped again. Had to disable the fan on the box. Then it worked ok. Tried another little star and this time it worked. Left the box off till we could get the box fan working. |
|
| 041112 | td4 | jack released. kolmorgan power supply failed...replaced
15nov04. It had a short. also changed the dac board and signal conditioning. |
|
| 040510 | td4 | loud noise from the jack. replaced the jack. This required dismantling the limit switches, encoder and then replaced after new jack installed. reference may have moved some. (our tape measurement were not longer valid since new jack). | |
| 040317 | td8 | safety relay problem was water in liftoff switches. Only had 15 volts rather then 24. Cleaned the switch and it started working. | |
| 040317 | td8 | db25 feed thru filter for pc. Replaced it and the pcu started working. | |
| 040315 | pcu | pcu was not working . brought it up to the lab to check it out. (problem was feed thru filter td8) | |
| 040315 | 8 | safety relay was not closing with result pulse. after cycling it manually a few times it started to work. Switched pcu relay with safety relay. problem was feed water in switch. ( see 040317) | |
| 040315 | 4 | encoder jumping to 24". started 4th march, 12 march shut off. 15mar replaced encoder intf board. | |
| 030930 | mod4 | changed little star td4 (battery was low). updated parameters in little star. | |
| 030806 | mod 8 |
recalibrated loadcells on td 8 | |
| 030806 | mod 4 |
rotated mounting bracket for limit switches to face away from the box. Old tape measurements no longer valid for td4. | |
| 030730 | mod 8 |
final lower limit td 8 reset to be at encoder position 1.19". Ran the jack all the way to 0" encoder value and still did not hit end of jack (although it is probably pretty close). | |
| 030728 | Note | The limit switches were changed to a newer type that did not leak (i'm not sure what date). It looks like they were mounted in the same position as the old switches even though the mechanical layout is different. The jack positions for where the limits triggered are now different. For td8, the jack runs all the way to the end of the jack and the limit switch has still not tripped. This is what caused the limits to not trip on 030728. All of the limit switches need to be repositioned so they are at the correct jack positions. | |
| 030728 | Fail | lightning afternoon. | |
| 8 | blew out dac. Td went all the way up. Final limit switch
did not trip. Replaced dac. Final limit switch has moved by more than 1 inch. Probably not the encoder since we actually ran into the end of the jack without hitting the limit. |
||
| 4 | Encoder board blown. Replaced board. Encoder before problem was 13.301. After it was 12.6?? Someone must have moved the td while board was bad. Since abs encoder was ok, position is probably ok | ||
| 031111 | Fail 4 |
td4 drive disabled itself even though program thought it
was still running. Luis found that the voltage regulator for the dac was shorted. Replaced dac. |
|
| 021003 | mod all |
5 volt supply for dacs is now coming from a separate power supply. It used to come from the dc to dc converter on the encoder board. Change made to t12. Need to also update the others. Need to move the 5 volt encoder voltage monitoring line from the dac to the a/d. | |
| 021002 | Fail | lightning | |
| 12 | blew out encoder interface. replaced. The kips were reading 81,82 until the encoder board was replaced. The lcd display on 12 was also acting up. | ||
| 8 | blew out encoder interface board. replaced. Recalibrated td8 load cells. |
||
| 020923
|
fail 8 |
Axis fault always on. tiedown was oscillating. This can be
from encoder init error or master contactor did not close
after 20 cycles. This encoder interface board had been
installed 10sep02. Replacing the encoder interface board
fixed the problem. Updated the zero velocity offsets for td12 and td8. |
|
| 020910 | fail | lightning struck platform. | |
| 12 | signal conditioning bad. Dac may also have been blown. Swapping encoder interface board screwed up dac or signal conditioning again.. This was an old encoder interface board. roc 424. | ||
| 8 | encoder bad. Dac or signal conditioning also bad. | ||
| 020815 | fail | power dip or lightning?? | |
| 12 | dac output reading -2048 counts. cycling power fixed it. | ||
| 4 | dac signal conditioning board blew. Outputting -24 volts. | ||
| 8 | encoder reading 24 inches. encoder interface replaced with new encoder board/pal (425q pals. | ||
| 020424
|
fail 8
|
power dip td8 not responding. +24 pwr supply has 3.5 volts. Removing little star fixed it so little start was shorting out pwr supply. Put in new little star, didn't work. Put in 2nd little start. Worked but had to update parameters. After updating parameters, would only move up , not down. Maxpos was 0 so i set it to 24000. Next day rebooted and it worked ok. Looks like for some parameters you need a reboot to take affect. |
|
| 011203 | fail8 | lightning . td 8 dead. Short in +24 volt power supply. | |
| 011101 | fail8 | little start digital input lspin09 bad. opto-isolator on signal conditioning board shot. This caused the master contactor to always read closed, even when it was open. | |
| 011101 | all | Tiedowns back on the air. They'd been off since 23sep01 | |
| 011101
|
fail 8
|
amplifier for td8 amp had missing connections on a capacitor, resistor, and a blown capacitor. Replaced amp with repaired amp from kolmorgan. This amp had speed offset for the azimuth (it was an az motor). On td this caused and over speed. The dac output was 8 volts and the speed output (of amp) was over 11 volts. Tried adjusting a pot to bring the speed voltage to 0 but it looks like it screwed up the gain. Installed another amp and it worked ok. | |
| 011031
|
fail8
|
load cell td8 amp1 jumped 1.2 volts in dc offset. (ldcell:#90407). Switched cables at output of load cells and still had the problem. Removed db25 connector at case and it worked ok. Replaced connector (these connectors have built in filters). Measured the resistance for the wheatstone bridge in td8,4 load cells. records in manual so you can easily check if the db25 connector is blown (it changes the resistance). | |
| 011030 | mod | Td 8,td4 now have roq424/425 encoders. They work fine. Td
12 has old roq424 encoder. it jumps in the 3rd hex digit
from the right. Td8 A/D card jumper was not cut. did it today. |
|
| 011029 | mod | Replaced ldcell amp td8 #1. Recalibrated (but the a/d resistor had not been cut. | |
| 010923 | fail | lightning. tiedowns remain down until 01nov01 | |
| 12
|
encoder moving in wrong direction. Changed encoder,
started to move and then little start died. changed little
start. Luis had measured the position at 14.7 inches. So
moved td to luis's tape measurement and then set the encoder
to 14.7 inches. Then went to the limits and got: expected measured 1.43 1.8473 .4 inches off 22.29 22.28 .01 inches off |
||
| 4 | encoder reads 24 inches. resetting td 4 seemed to fix it , but moving 4 then made a terrible noise. Dac is shot, red light is off. Replaced dac and switched to single ended mode on signal conditioning board (no jumper and 10k resistor). | ||
| 8 | encoder reads 24 inches. cycling power it then reads 0
inches. Lifted bus cable to dac,di1,di2 and a/d started working. looks like dac is screwing up bus. Replaced dac, signal conditioning. still troubles. looks like encoder board is messing up the bus (need to build some more encoder boards for the new encoders). |
| date |
td |
description |
| 200228 |
4 |
td 4 jack replaced (new one installed and
running on 200303) |
| 170901 |
8 |
tiedown jack replaced |
| 170827 |
12 |
tiedown jack replaced |
| 170825 |
4 |
tiedown jack replaced. |
| 1601xx |
8 |
load cell 2 replaced. damaged during hf run
back in nov15 |
| 120423 |
12 |
tiedown jack replaced |
| 120516 |
8 |
jack replaced? more info |
| 090109 |
12 |
tiedown jack replaced |
| 080619 |
4 |
transmission replaced |
| 080529 |
4 |
tiedown jack replaced |
| 080228 |
12 |
transmission replaced. had a
loud knocking sound |
| 050605 |
8 |
according to felipe soberal |
| 050317 |
12 |
tiedown jack replaced |
| 050225 |
4 |
tiedown jack replaced. |