[Isocops] IBEX CEU SOH check for Orbits 168-170.

[Mark Tapley]

IBEX instrument teams,
	Orbits leading up to and including the 1st 2 -Lo safing events.
	Most of the noted features have been discussed thoroughly, 
but I have not heard discussion of the change in the character of the 
-Lo LV power supplies (3.3V, 5V, 6V), all of which show markedly 
reduced "noise" in the measurements in the orbit prior to safing.


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

	For Arc 168a: No obvious spin problems. IBEX-Hi Positive 
Collimator Current has "fuzz" around days 2.5 and 3.5. IBEX-Lo PAC 
Current monitor exceeds yellow limit at start-up for 1 sample. 
Otherwise nominal.

	For Arc 168b: Spin problem around day 3.5; ACS performance 
agrees, with FractionValid dipping to 5% around day 2.5, and again at 
end of orbit. IBEX-Lo PAC Current monitor exceeds yellow limit at 
start-up for 1 sample. Otherwise nominal.

	For Arc 169a: No obvious spin problems. IBEX-Lo MCP Volt 
monitor shows one drop-out. IBEX-Lo TOF Positive 3.3, 5V, and 6V 
monitors are unusually quiet. Otherwise nominal.

	For Arc 169b: No obvious spin problems. IBEX-Lo LV current 
monitor and Volt monitor are unusually quiet, railed against the 
lower values. IBEX-Lo 3.3, 5, and 6V monitors are even quieter than 
in arc a, very unusually so.




	For Arc 170a: No obvious spin problems. IBEX-Lo data cuts off 
around day 0.5, with a brief reappearance around day 1.8.

	IBEX-Lo LV current monitor is very quiet before safing, and 
shows one (noise?) red high value at restart.

	IBEX-Lo LV Volt monitor is unusually quiet while running, and 
shows one red low value at re-start.

	IBEX-Lo MCP Current monitor has been discussed elsewhere; 
mostly expected values with a few high values (but below yellow 
limits) just prior to safing.

	IBEX-Lo PAC Current Monitor has been discussed ad nauseum 
elsewhere; yellow high values just before second safing, slight 
increase before first statement; as often happens, yellow high for 
one value at start-up.

	IBEX-Lo TOF 3.3, 5, and 6V monitors are unusually quiet 
again, while running; 5V Current shows response to temperature.

	Other parameters as grouped below:
Temperature response apparently correlated to eclipse and -Lo power state:
	...
	CEU temperature ( -20 C during eclipse, -3 C for -Lo power-off)
	IBEX-Hi temperature, HV Power Supply Temperature
	IBEX-Lo IFB and LV Temperatures (one red low value at turn-on)
	IBEX-Lo MCP, PAC, and TOF Temperatures
	IBEX-Lo Temperature

Response apparently correlated to temperature only:
	...
	Spin Rate Error (ACM data)
	IBEX-HI CEM current (10% dip during eclipse)
	IBEX-Hi Suppression Grid Voltage (15% dip during eclipse)
	Positive 7.5 Volt CEU Switch Current

Respond as expected to safings and restart, with temperature-related changes:
	...
	IBEX-Lo TOF MCP Current Monitor
	Negative 12 Volt CEU Switch Current
	Payload +12V PS Voltage
	Positive 5 Volt CEU Switch Current

Respond as expected to safings and restart:
	...
	IBEX-HI ESA Voltage
	IBEX-Lo Negative Collimator Voltage
	IBEX-Lo - and + IFB 12 V Monitors (one red low value at start - noise?)
	IBEX-Lo MCP volt monitor
	IBEX-Lo PAC Volt Monitor (one low value at first safing)
	IBEX-Lo PMT Voltage
	IBEX-Lo TOF MCP Volt monitor
	MCP Voltage setting
	PAC Voltage Setting
	Positive 12 Volt CEU Switch Current



	For Arc 170b: No obvious spin problems. Many values are 
consistent with -Lo being off. 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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