Notes on homing motors

Note: Type showmot on waikoko before re-homing motors to be sure that it is necessary first.

Record of motor homing following February 26, 2007 power failure

All but SLS, SLM and CAM homed OK first time using steps given on troubleshooting page.

SLS: First posname worked, but with the "Homing stopped at 22 counts ..." error.
SLM: First failed with "Aborting ... motion to stop" (showmot shows 144772, second, got there (and set to 514000), but POSITION_FLT so had to mm slmraw=51000.
CAM: First poshome failed with "RBp error" at 33678. Second one got the "Stopped at 23 counts ..." error and showed STALL_FLT. Cleared with mm camraw=431000.

Record of motor homing following February 20, 2007 power failure.

All but SLS,SLM,CAR homed OK first time using steps given on troublewhooting page.

SLS: After the mm slsreset=1 and the mm slsinit=1, successfully used poshome sls after 3 tries. Raw values from showmot showed about 200000 counts motion between the first two that did not make it. The poshome script reports "Aborting because An error occurred while waiting for motion to stop" in these cases. Note that we use the positive (physically higher in the instrument) limit for SLS and SLM because over time gravity has taken its toll (roughly speaking). Once the the poshome script shows "true" in the home column and gives the different error message "Homing stopped at 23 counts from index ...", then just back it off a little with "mm slsraw=510000" and then the status will change from POSITION_FLT to IDLE.
SLM: Pretty much same as SLM. May have required fewer tries (2).
CAM: After the mm camreset=1 and themm caminit=1, three tries poshome cam and it arrived at the 434000 limit and gave a "true" in the home column of showmot, but, unlike SLS/SLM, it showed STALL_FLT and during the tries that didn't make it, poshome reported "RBp failed ..." instead of "Aborting because An error occurred while waiting for motion to stop", but other than that similar to the SLM/SLS behavior. Again, used raw move to nearby position to clear the fault status to IDLE (mm camraw=433000).

Record of motor homing following May 18, 2007 power interruption (switch install).

SLS:
- poshome sls try #1 -- failed with "on first approach stopped at -20 from the index mark" raw is 514000
- poshome sls try #2 -- failed with "on first approach stopped at -20 from the index mark" raw is 514000 again
- mm slshome=1 -- STALL_FLT at 19903
- poshome slstry #3 -- STALL_FLT at 163866
- poshome sls try #4 -- STALL_FLT at 308641 (note 200000 difference like last time)
- poshome sls try #5 -- STALL_FLT at 453264
- poshome sls try #6 As above: script shows "true" in the home column and gives the different error message "Homing stopped at 23 counts from index ...", backed it off a little with mm slsraw=510000 and then the status will change from POSITION_FLT to IDLE.
SLM:
- poshome slm try #1 -- failed at 144281
- poshome slm try #2 As above: script shows "true" in the home column and gives the different error message "Homing stopped at 23 counts from index ...", backed it off a little with mm slmraw=510000 and then the status will change from POSITION_FLT to IDLE.
CAM:
- poshome cam try #1 -- failed at 144111
- poshome cam try #2 -- failed at 165014 (RBp message)
- poshome cam try #3 -- "Aborting because An error occurred while waiting for motion to stop", but other than that similar to the SLM/SLS behavior. Again, used raw move to nearby position to clear the fault status to IDLE (mm camraw=433000).

	Notes on homing motors
NIRC2 Home Page NEWS Temps Troubleshooting Index Keck Instrument Ready? Archive (KOA) Observer Home Page Tel Schedule Instruments Home Keck Home Observing Info ToO Policies Weather MK Forecast CFHT SkyProbe MK Seeing CFHT Cloudcam Summit Cams Keck Cloud Cams Planning Tools Starlist Tool Finding Charts IRSA Finder Charts Observing Planning Tool Offset/PA Tool Contact Us Contact Info Post-Observing Comment Form WWW Keck Web Site	Note: Type `showmot` on waikoko before re-homing motors to be sure that it is necessary first. Record of motor homing following February 26, 2007 power failure All but SLS, SLM and CAM homed OK first time using steps given on troubleshooting page. SLS: First posname worked, but with the "Homing stopped at 22 counts ..." error. SLM: First failed with "Aborting ... motion to stop" (`showmot` shows 144772, second, got there (and set to 514000), but `POSITION_FLT` so had to `mm slmraw=51000`. CAM: First poshome failed with "RBp error" at 33678. Second one got the "Stopped at 23 counts ..." error and showed `STALL_FLT`. Cleared with `mm camraw=431000`. Record of motor homing following February 20, 2007 power failure. All but SLS,SLM,CAR homed OK first time using steps given on troublewhooting page. SLS: After the `mm slsreset=1` and the `mm slsinit=1`, successfully used `poshome sls` after 3 tries. Raw values from `showmot` showed about 200000 counts motion between the first two that did not make it. The poshome script reports "Aborting because An error occurred while waiting for motion to stop" in these cases. Note that we use the positive (physically higher in the instrument) limit for SLS and SLM because over time gravity has taken its toll (roughly speaking). Once the the `poshome` script shows "true" in the home column and gives the different error message "Homing stopped at 23 counts from index ...", then just back it off a little with `"mm slsraw=510000"` and then the status will change from `POSITION_FLT` to `IDLE`. SLM: Pretty much same as SLM. May have required fewer tries (2). CAM: After the `mm camreset=1` and the`mm caminit=1`, three tries `poshome cam` and it arrived at the 434000 limit and gave a "true" in the home column of showmot, but, unlike SLS/SLM, it showed `STALL_FLT` and during the tries that didn't make it, poshome reported "RBp failed ..." instead of "Aborting because An error occurred while waiting for motion to stop", but other than that similar to the SLM/SLS behavior. Again, used raw move to nearby position to clear the fault status to `IDLE` (`mm camraw=433000`). Record of motor homing following May 18, 2007 power interruption (switch install). SLS: `poshome sls` try #1 -- failed with "on first approach stopped at -20 from the index mark" raw is 514000 `poshome sls` try #2 -- failed with "on first approach stopped at -20 from the index mark" raw is 514000 again `mm slshome=1` -- `STALL_FLT` at 19903 `poshome sls`try #3 -- `STALL_FLT` at 163866 `poshome sls` try #4 -- `STALL_FLT` at 308641 (note 200000 difference like last time) `poshome sls` try #5 -- `STALL_FLT` at 453264 `poshome sls` try #6 As above: script shows "true" in the home column and gives the different error message "Homing stopped at 23 counts from index ...", backed it off a little with `mm slsraw=510000` and then the status will change from `POSITION_FLT` to `IDLE`. SLM: `poshome slm` try #1 -- failed at 144281 `poshome slm` try #2 As above: script shows "true" in the home column and gives the different error message "Homing stopped at 23 counts from index ...", backed it off a little with `mm slmraw=510000` and then the status will change from `POSITION_FLT` to `IDLE`. CAM: `poshome cam` try #1 -- failed at 144111 `poshome cam` try #2 -- failed at 165014 (RBp message) `poshome cam` try #3 -- "Aborting because An error occurred while waiting for motion to stop", but other than that similar to the SLM/SLS behavior. Again, used raw move to nearby position to clear the fault status to `IDLE` (`mm camraw=433000`).
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