Throughout the day, the CDS group performed multiple updates (cf Dave & Vern ALOG for details). When the computers were handed back to the users, I encountered some difficulties to restore HEPI BSC6. First, I was surprised by the large offsets on the position sensors (>10K counts ~ 15mils). Then, I realized that the pump was turned off. But after turning the pump back on, the HEPI did not come back to its nominal position. Some tests are currently being performed to understand what’s wrong with the HEPI at the end station.
I have attached the IPS readouts measured during the last 10 days. We clearly see that the HEPI position changed after the pump was shut down.