Travis and Gerardo installed the in-vac Septum flange Wilcoxon single-axis-accelerometer in Nov 2017 (it is oriented in "-Y").  This is under Ticket #4512.

There was a thought of installing additional in-vacuum accelerometers since the in-vac Wilcoxon cable can accommodate up to 8 accelerometers.  At LLO one was installed on the OMC cage, but it was deemed not useful.  So we opted to NOT install one on the H1 OMC.  There was mention of an accelerometer on another axis on the septum would be useful, but since we are under vacuum on the other side of HAM6, that is not possible (& not sure if the clamps can accommodate this).

At any rate, I went ahead and connected the cable to the in-vac side of the D-Flange (specifically:  Connector D1 3C2).  This cable does not contact the ISI at all; it is in fact, spooled up in the "nozzle" at the Septum.

Photos are attached (the first one is a panoramic [hence no thumbnail preview] showing from flange to flange.)

There is no in-air cable attached.  Richard says they can connect something up whenever someone wants to use this accelerometer for testing.