J. Kissel

I've performed our regular charge measurements for the week of 2016-07-20. Because we had lack acquisition troubles leading up to ER9 with flipping the bias sign (see LHo aLOGs 28362, 28152), we've left the signs on both end test masses where they were about a month ago (see LHO aLOG 27890). As such, the charge continues to accumulate in the directions they were. 

ETMX (perhaps because we've had such a low IFO duty cycle) has begun to accumulate charge more rapidly that a few months ago. Thus, we'll *need* to flip the sign sooner than expected -- but it's still OK for now. 
ETMY is still within -10 [V] effective bias. 

However, if we'd like to use this charge mitigation method for ER10 and O2, we should continue trying to flip the bias regularly and debug what's wrong with the lock acquisition sequence when we do. Will try again when we have a little more patience (i.e. in the mornings when we first arrive, while we [the detector engineering and operations teams] get the IFO locked and ready for the commissioning vanguard).