Dan, Corey, Keita, Hugh, Jeff
Today we started the HAM6 installation procedure outlined in T1400385. After the north and south doors came off (and the east door was put back on), Hugh installed ISI ballast on the business end of the table while Corey checked cables. We found we were missing two cables, to carry the OMCR-QPD and AS-C-QPD signals from the brackets on the table to the flange (cables 4 and 10, in section 6 of the procedure). Also, we discovered a discrepancy between the flange layout document (D1002877) and the WHAM6 cable configuration (D1300122). The flange layout correctly assigns feedthrough D5-3C to the purge air, and the WFS head cables exit the chamber through D3-2C. According to the cable configuration the WFS head cables are going through the purge air feedthrough.
Another small discrepancy is the assignment of the OMC DCPD and PZT cables in bracket CB-1, on the top of the OMC suspension cage. The cables are swapped from the locations prescribed in D1300122; the DCPD cable is on the second floor, the PZT cable is on the first floor. (The connections at the flange are correct, so no worry of powering the DCPDs with the PZT drive.) We tried to correct the bracket arrangement but discovered that the PZT cable is too short to reach the second floor of the bracket, so we left things as we found them.
We found two spare cables with Betsy for the OMCR and AS QPDs and attached those to the flange and the brackets. The OMC suspension was moved flush against the cookie cutter, and we installed & torqued the dog clamps. (The dog clamps are the incorrect height, but this seems to be a systemic issue.)
Now that we have finished verifying the cable connections by eye, the next steps are (not necessarily in this order):
- swap mirror M7 into a picomotor mount
- arrange tip-tilts, mirrors, and lenses in the correct optical paths (to be aligned when we get beam)
- install WFS and QPD sleds
- flash diodes, check electronics
- unlock the OMC SUS and check the OSEMs
We may need to switch between moving sleds/optics and installing ballast mass as we move through the procedure.