NOAA-14 SSU Turn Off, FW: N14 Battery Voltage Concerns

NOAA-14 SSU Turn Off, FW: N14 Battery Voltage Concerns

*Date/Time(UTC) Message Issued*:
5May 2006 time 11:35 EST

*Satellite(s) Involved*:

*Instrument(s) Involved*:

*Product(s) Involved/Affected*:
All SSU Products

*Date/Time(UTC) of Initial Implementation*:
5 May 2006, Time 1842 UTC

*Details/Specifics of Change*:
The battery voltages on NOAA-14 have reached dangerously low levels. In order to prevent a power survival safe state it is necessary that we turn something off to reduce the load. The SSU has been selected for that turn off, and we currently plan to turn it off during the pass at 18:42z on Friday, May 5th. We expect that the power situation will improve in a couple of months as the eclipse season ends. At that point we should be able to turn the SSU back on.

*********Original Message----- Thursday, May 04, 2006 11:03 AM **********

Subject: Re: N14 Battery Voltage Concerns

As we have been saying the battery voltages on N14 are running at all time lows and are expected to go even lower at least for another month. Carl Gliniak has studied this situation closely and is of the opinion, of which I also concur, that we should try to shed a load on N14 to bring these voltages up. At the present time the SSU would be a good candidate for powering off as it would bring the low voltage up to about 20.1 volts (vs 19.76 which recently occured during a PARTIAL PASS). Carl has spoken with Dong and he said turning off the SSU is OK with him. How would you like us to proceed (as mentioned at the Tuesday meeting, we have some extra power consumption requirements coming up for the no momentum unload test.)