We've observed some burn marks on the shielding of the ETMy ring heater cables which occured sometime during the 3 prior weld sessions (May 2012, Dec 2013, Jan 2014). The burns are on the lowest ring heater cable that laces around the test mass and makes a connection between the test mass and the PUM. There is a burn on the right segment and the left segment. I dug up a picture that shows that the burn on the "right" segment (as viewed from the back of the suspension) was there just after the May 2012 weld session, so that one is not new. However the "left" cable burn is new from the Dec or Jan welding. We did not see when this actually occured.
Filiberto tested the ring heater cable and found that all pins are operating as per spec, although he thinks pin 1 is shorting. We are tracking down what this means (did we test it correctly, when was it last tested, is it possible that the burn is contributing to the short, even though it does not look like it is, etc.).
This is the picture of the RH "right" cable taken in May 2012.
And here is the "left" RH segment burn which happened in the Dec or Jan weld.