ACE Weekly 07/10/2012 - 07/16/2012

All ACE spacecraft subsystems are performing as expected.  The
SWEPAM-Electron overcount alarm stopped flagging when the noisy CEM (#2)
was masked off.  See OCRs below.

========================================================================
Orbit/Attitude:

	Type        Attitude
	Date        07/12/2012
	DOY         194 2012
	Thrusters   2R 4R+ 4R-
	Duration    17:06 min
	Start       18:08:12z
	Stop        18:25:18z
	HGAStart    -8.15deg
	HGAStop     +7.75deg
	SunStart     5.74deg
	SunStop     14.85deg
	SpinStart   5.0588rpm
	SpinStop    5.0632rpm
	Nutation     0.08deg
	Firing      87 pulses
	FuelUsed      0.2627lbs
	FuelRemain  120.6628lbs
	FinalSCMass 1354.923lbs

The next attitude maneuver is scheduled for Thursday 08/02/2012.

=======================================================================
OCRs:

DOY 193 (07/11/2012) 1823-1833z  SWPE-044  SWEPAM-E v1.14 Code Dump
As part of the analysis of the SWEPAM-E overcount alarm, a dump of the
entire on-board executable image was performed.

DOY 198 (07/16/2012) 1803-1804z  SWPE-045  SWEPAM-E Mask CEM #2
Recent analysis shows that the SWEPAM-Electron Channel Electron
Multiplier (CEM) #2 (of 0-6, SWEPAM-E has 7) has become noisy which was
causing the overcount alarm to flag.  That channel has been masked and
the overcount alarm has stopped.  The possibility of noisy Channel
Electron Multipliers was planned for when the instrument was built.

Background Information:
The SWEPAM-E overcount alarm started flagging intermittently on
1/22/2012.  The alarm was flagging ~45% of the time in April and May;
and almost continuously since 6/1/2012.  The overcount alarm causes the
instrument's voltages to be reduced and results in little scientifically
useful data.  Cumulatively, the overcount alarm had flagged for 73.5
days over the past 6 months.

Preliminary from the instrument team concerning CEM #2 data being zeroed
out:  "There will be holes in the measured distribution.  The effect on
the scientifically-useful pitch angle distribution will be variable,
depending on the magnetic field orientation relative to the instrument
FOV, but we should be able to observe well-resolved distributions most
of the time."  Which is significantly better than having the instrument
in continuous overcount alarm.

DOY 198 (07/16/2012) 1805-1806z SWPI-046 SWEPAM-I CEM Voltage increase
The instrument team has increased the CEM voltage level on the
SWEPAM-Ion instrument from 2 to 3 (max possible=15) to determine if this
improves instrument performance.

========================================================================
Activities:

Data Capture:  100%  DOY 190-197 2012

During last week's solar activity, the ULEIS shutter autonomously closed
and reopened
	Sat Jul 14 2012, DOY 196 15:21:12z closed to 25%
	Sat Jul 14 2012, DOY 196 17:27:04z closed to 6%
	Sun Jul 15 2012, DOY 197 07:23:20z opened to 25%
	Sun Jul 15 2012, DOY 197 09:46:16z opened to 100%

========================================================================
Anomalies:

DOY 192 07/10/2012  S-ACE-0646  G12-0008  DSS-27 Red
The ground station's UPS tripped off causing the station to lose power.
After power was restored, the station had problems with the uplink
equipment.  The uplink was available 13 minutes before the end of the
pass, but too late to perform any activities.  DR# G112964 & G112965
IMPACT:  No pass activities performed.  Data was recovered on the
following pass.  No SSR failover since there was less than 43 hours
between the pass on Monday (7/9) and Wednesday (7/11).  NOAA SWPC was
not impacted since the spacecraft remained in the RTSW format.

DOY 194 07/12/2012  No SOAR generated     DSS-27 Antenna pointing
The ground station had antenna pointing problems (+350 mdeg offset) due
to an azimuth encoder issue.  There was no data loss and therefore no
anomaly report generated.  But the downlink signal strength was reduced
from -121dBm to -137dBm before the pointing was adjusted.  DR# G112990

DOY 196 07/14/2012  S-ACE-0523  S10-0007  Increase in SBE_CT_B
SSR B Single Bit Error Count (SBE_CT_B) increased from 12864 to 13302
between 7/12/2012 and 7/14/2012.  SBE_CT is tracked as a measure of SSR
health.
IMPACT:  Minimal.  Single Bit Errors are automatically corrected by the
SSR.  No non-correctable errors (Hard Single Bit Errors & Double Bit
Errors) have occurred throughout the mission.

	       SBE_CT_A  SBE_CT_B
	1999   15
	2000
	2001
	2002
	2003   270       286
	2004             858
	2005
	2006             2118
	2007   510       3238
	2008             4533
	2009   525       6839
	2010   780       7339
	2011             10995
	2012             13302