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Unexpected SD 722 Lithium Battery Failure (was SD 702 co

Subject: Unexpected SD 722 Lithium Battery Failure (was SD 702 co
From: "Rob Danielson" danielson_audio
Date: Mon May 19, 2008 8:46 am ((PDT))
At 6:19 AM +0000 5/19/08, John Hartog wrote:
>>Hi Rob, you say, "You can also set the "shut-off" voltage lower, like
>>10 volts when you use the external DC input."
>>
>>Though I have not tried using an external pack without an attached
>>battery also installed, at least on the 702 I think that setting you
>>mention only changes the the low voltage indicator and warning alarm,
>>but the switch over voltage (if I remember correctly, ~7 volts )is not
>>changeable.



Hi John--

Yes, that is correct. The 7XX's automatically shut-off or switches 
over to the 7.2 volt battery when external power drops to 9 volts. My 
mantra is "No such thing as too much power,"  but a setting of "10 
volts" serves as a better warning for me than the factory preset of 
11 volts when using my higher voltage or larger capacity external 
batteries. Its a great feature that you can check the ext power 
voltage as you leave a rig running. Many times I've discovered I had 
not charged a battery when I thought I had.

>
>>I still have not solved my battery switch-over problem that results in
>>corrupted files.
>

I poked in some terms on the SD Support search and didn't come up 
with anything. Maybe there a failure prompt you can search verbatim. 
Gosh, I did not know the problem was that serious.

I've never had this happen with my 744T. Even with a sudden AC 
adapter or external power loss, my 744T has always closed out the 
sound files on the HD powered by the 7.2 volt battery. The deck also 
notifies me upon re-powering that it was powered down incorrectly and 
asks if I want to check for any lost files on the HD.  So the theory 
is the problem is unique to CF media?

Its along shot, but how is your Hirose external battery connecter 
wired? Pin 1(-) and 4(+) should provide power without charging the 
removable 7.2 volt battery and the configuration of pin 1(-)  and pin 
3 (+) should provide power and charge the removable 7.2 volt battery. 
I use the later wiring on my primary Hirose cables so I'll head off 
to field with the external and 7.2 v batteries fully-charged. Keeps 
the 7.2 battery topped off as they do drop power sitting. Rob D.
>
>>I set the file size limit to around <2GB to allow for
>>easier DVD archiving: this has turned out to save me some important
>>recordings as it is only the last file being written when the failure
>>occurs that gets corrupted.
>>
>>John Hartog
>--
>


-- 






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