[Isocops] IBEX CEU SOH check for Orbits 148-151. * RED LIMITS on V and T *

[Mark Tapley]

IBEX instrument teams,
	Still working; commanded and expected RED LIMITS continue on 
IBEX-Hi Negative Collimator Voltage. Note, system design should 
accommodate -3100V, and maximum commanded voltage is -1600V, so limit 
on plot does in fact need revision.
	A different RED LIMIT occurs on IBEX-Lo TOF Temperature Arc 
149b. This is almost certainly spurious; it's only a single reading, 
no temperature ramp-up or -down.

--------------------

	For Arc 148a: Serious spin problems, last 1/3 of arc. ACS 
shows FractionValid going to near zero. As noted in previous report, 
IBEX-Hi Negative Collimator Voltage is commanded to RED LIMIT of 
1300V. IBEx-Lo PAC Current Monitor seems to exceed yellow high 
current for one sample at ramp-up; this is a fairly normal 
occurrence. Otherwise Nominal.

	For Arc 148b: Serious spin problems, first day or so. ACS 
shows FractionValid at near zero, returning slowly to 100%, then 
dipping again near end of orbit. IBEX-Hi ESA Voltage shows several 
excursions to zero near the end of the arc, consistent with a gain 
scan. A descending staircase patter also appears in IBEX-Lo MCP 
Current Monitor, in IBEX-Lo MCP Volt Monitor, IBEX-Lo TOF MCP Current 
Monitor, IBEX-Lo TOF MCP Volt Monitor, and MCP Voltage Setting. 
Otherwise Nominal.

	For Arc 149a: Serious spin problems, first day or so. ACS 
shows FractionValid near zero, recovering around day 1. As noted in 
previous report, IBEX-Hi Negative Collimator Voltage is commanded to 
-1400V which is beyond plot RED LIMIT of -1300V. IBEX-Hi CEM Current 
shows a series of stair-steps consistent with a gain scan around Day 
1.7, also reflected in IBEX-Hi CEM Voltage (with CEM 4 offset ~100V 
above the others this time), IBEX-Hi ESA Voltage excursions to zero, 
and IBEX-Hi TOF Box Voltage (set back to -5500V from -6000 during the 
scan). Otherwise Nominal.

	For Arc 149b: No obvious spin problems. IBEX-Lo MCP Volt 
monitor shows 2 drop-outs, in the middle of the "fuzz suppression" 
due to IBEX-Lo PMT Voltage set-back. *** IBEX-Lo TOF Temperature 
shows a single (almost certainly spurious) reading above the RED 
LIMIT about day 4.7. ***. Otherwise Nominal.

	For Arc 150a: Spin rate looks good, but a phase offset is 
corrected around Day 1. FractionValid, which had been around zero, is 
returning to 100% around that time. As noted in previous report, 
IBEX-Hi Negative Collimator Voltage is commanded to -1400V which is 
beyond plot RED LIMIT of -1300V. Otherwise Nominal.

	For Arc 150b: No obvious spin problems. IBEX-Hi ESA Voltage 
goes to zero once near beginning and once near end of arc, consistent 
with O-Mode operation as commanded. Otherwise Nominal.

	For Arc 151a: Spin problems for first 1.5 days; FractionValid 
goes to zero during most of that time, then recovers to 100%. As 
noted in previous report, IBEX-Hi Negative Collimator Voltage is 
commanded to -1400V which is beyond plot RED LIMIT of -1300V. IBEX-Hi 
ESA Voltage goes to zero once near beginning and once near end of 
arc, consistent with O-Mode operation as commanded. "Fuzz" as often 
before, modulated by IBEX-Lo PMT Voltage. Otherwise Nominal.

	For Arc 151b: Spin problems for last ~1 day of orbit; 
FractionValid has been decaying all Arc, goes to ~10% for last day 
and ACS indicates loss of spin lock. Noticeable IBEx-HI CEM Back 
Counts day 8.7. IBEX-Hi ESA Voltage goes to zero once near beginning 
and once near end of arc, consistent with O-Mode operation as 
commanded. Otherwise Nominal.

--------------------


...based on data at http://ibex.unh.edu/ibexhome/id-leops/status/ in 
appropriate directories.
-- 
						- Mark     210-379-4635
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