Taperssection.com

Gear / Technical Help => Remote Power => Topic started by: mikesalvo on January 18, 2009, 10:24:20 PM

Title: whats that formula that figures out batery life based on mah/voltage?`
Post by: mikesalvo on January 18, 2009, 10:24:20 PM
isnt there a way to figure out how approximately much life you can get out of an external battery based on taking the maH of your external battery and the voltage of your device??? I cant seem to find it. I know it exists. is it simply dividing the two #'s?
Title: Re: whats that formula that figures out batery life based on mah/voltage?`
Post by: cmoorevt on January 18, 2009, 10:35:59 PM
Quote from: mikesalvo on January 18, 2009, 10:24:20 PM
is it simply dividing the two #'s?

Yes.  Divide the mAh of the battery by the mA draw of your device.  I'm pretty sure the UA5 draws 450mA
Title: Re: whats that formula that figures out batery life based on mah/voltage?`
Post by: mikesalvo on January 18, 2009, 10:41:02 PM
right on, thanks Chris. I should have actually been more specific...I am inquiring primarily about the iRiver...Anyone know what th draw of he iRiver is?

btw Chris, how did youre Avett pull come out @ The Chandler that night? I LOVE that place. Can wait to get back there @ some point.
Title: Re: whats that formula that figures out batery life based on mah/voltage?`
Post by: twatts (pants are so over-rated...) on January 18, 2009, 10:46:35 PM
Volts of the battery need to match the Volts of the device - 12v device needs 12v battery.

To figure out what you need, you need to find out the "draw" of your device, or how many amps it uses.  If your device has a draw of 100amps, a 100amp/hour battery will power it at full voltage for 1hour. 

In a typical case, the Tascam HD-P2 has a "Power Consumption" of 6W (watts).  6W = 12V x ___Amps, or 0.5Amps, or 500mA. 

A battery pack like this one:  http://www.batteryspace.com/index.asp?PageAction=VIEWPROD&ProdID=4011  will power the HD-P2 for 14hours (7000mAh/500mA = 14h).

What are you trying to power??? 

Terry
Title: Re: whats that formula that figures out batery life based on mah/voltage?`
Post by: mikesalvo on January 18, 2009, 10:59:54 PM
Quote from: mikesalvo on January 18, 2009, 10:41:02 PM
\.I am inquiring primarily about the iRiver...Anyone know what th draw of he iRiver is?

Title: Re: whats that formula that figures out batery life based on mah/voltage?`
Post by: twatts (pants are so over-rated...) on January 22, 2009, 11:45:20 AM
Quote from: mikesalvo on January 18, 2009, 10:41:02 PM
\.I am inquiring primarily about the iRiver...Anyone know what th draw of he iRiver is?



I bet these people know:

http://www.misticriver.net/forums/h1xx-specific-mods/4937-external-battery-pack-h100-series.html

Terry