On Wednesday before shutting down Hanford for today's power cut, I managed to do another measurment this time with the wire for the LL quadrant going through the ESD LP filter box instead of BIAS as it should have been. To be clear, this is the old configuration and we wanted to see the effects this cable configuration has on the charging measurements.

I have attached here the measurement documentation and the Veff plots for pitch and yaw which also include the measurement one day before for comparison.

The current measurement took place between UTC (2014-08-13 21:48:00) and UTC (2014-08-13 23:00:00), while the previous one took place between UTC (2014-08-12 17:17:00) and UTC (2014-08-12 19:09:00), the ESD LL quadrant wire swap too place at about UTC 2014-08-12 20:00:00. Notice that a couple of hours after the cable swap there was a power glitch which shutted down the ESD power supply so the ESD was not charged until the current measurements took place. This is something to take into acount, between the measurements compared in the plots and in the table below the ESD was off. I have verified that the ion pump, the iluminators and the cold cathode were on during this time (see plot below). Because looking at the Veff values in the table we see that after the cable swap the charge values did not change much, with the only exception of the quadrant that had a charge of opposite sign to the rest. This charge reversed once again to common sign to the other quadrants.