With Hirata-san.
See album SR2 Remedying work after O3.
According to report 18237, the coil in the IM-V3 OSEM had a higher resistance than expected (24.2 Ohm vs. 19.6 Ohm), so we investigated.
The OSEM is connected to the upper flange via three cable segments:
- Segment 1: from the OSEM to the BF.
- Segment 2: from the BF to the base of the preisolator.
- Segment 3: from the base of the preisolator to the flange.
We found that the problem is in the male connector at the upper end of segment 2. When some of the pins are touched the resistance varies a lot, including becoming an open circuit sometimes.
We aim to fix the connector early next week.