electricity comsumption

[vash]

specs. what does the power consumption mean? i have a 10 amp hour battery.


Nominal Supply Voltage 12 V DC
Operating Voltage Range 10.8 V DC to 15.6 V DC
Power Consumption At Full Brightness 5.3 W RMS
Connections Power / Transducer combined input
Waterproofing Standard IPX6 and IPX7
Display Size 5.0 in
Display Resolution 800 x 480 WVGA
Aspect Ratio 15:9

[GH85Carrera]

Most every battery backup and electronic device like to use different measures of the "draw" or consumption and they do that to make the number sound bigger.

So the will change from amps to watts and HP to kilowatts and BTU. First you have to start with a power scale, and convert the rating to the same scale to have an idea of what they are really using.

Like measuring vacuums it starts with PSI and suddenly changes to torr or microns.

[red-beard]

A 12V, 10 Amp-Hour battery has a nominal 120 Watt-hours of energy

It should last about 120/5.3 = ~22-23 hours.

The reality is the AH rating is at a specific discharge rate, which is usually 20 hours. Which is pretty close to your discharge rate. If you had a larger load, say 20 Watts, the discharge rate is much higher and the energy lost to heating is more. You would probably only get 8-9 Amp-Hours.

[Pazuzu]

a 10 amp-hour battery can supply 10 amps for one hour, or 5 amps for 2 hours, or 1 amp for 10 hours, or 0.5 amps for 20 hours.

Watts=Voltage*Amps
5.3=12*Amps Amps=5.3/12=.45 which is close to 0.5 amps
So, the 10 amp-hour battery will last a comfortable 20 hours.

[red-beard]

Originally Posted by Pazuzu

a 10 amp-hour battery can supply 10 amps for one hour, or 5 amps for 2 hours, or 1 amp for 10 hours, or 0.5 amps for 20 hours.

Watts=Voltage*Amps
5.3=12*Amps Amps=5.3/12=.45 which is close to 0.5 amps
So, the 10 amp-hour battery will last a comfortable 20 hours.

Sort of...But you need to look at the battery ratings. A 10 amp-hour battery discharging more than 0.5 amps will definitely not have full rating. If you discharge at 6 amps, it will discharge in 1 hour.

See here:

http://files.upgi.com:8086/UPGFileService.svc/GetSpecSheet/D5719

[vash]

Originally Posted by Pazuzu

a 10 amp-hour battery can supply 10 amps for one hour, or 5 amps for 2 hours, or 1 amp for 10 hours, or 0.5 amps for 20 hours.

Watts=Voltage*Amps
5.3=12*Amps Amps=5.3/12=.45 which is close to 0.5 amps
So, the 10 amp-hour battery will last a comfortable 20 hours.

thanks. you dumbed it down beautifully.

i cant see needing it for more than 16 hours on the rare occasion i need to use it for two 8-hours stints before recharging. most will be 8 hours.

[javadog]

5 Watts is almost nothing.

[Eric Coffey]

Originally Posted by red-beard

Sort of...But you need to look at the battery ratings. A 10 amp-hour battery discharging more than 0.5 amps will definitely not have full rating. If you discharge at 6 amps, it will discharge in 1 hour.

This.

The type (chemistry) and quality of battery factors in. You can have 2 batteries of the same voltage and capacity (AH), and one will do fine at higher loads (high-drain), while the other will drop off a cliff with the same load increase (and potentially be a fire hazard in extremes).

[Pazuzu]

Originally Posted by vash

thanks. you dumbed it down beautifully.

i cant see needing it for more than 16 hours on the rare occasion i need to use it for two 8-hours stints before recharging. most will be 8 hours.

You're welcome. I figured you wanted a down and dirty explanation, rather than a treatise on the inability of modern batteries to maintain power over time

[dad911]

Kayak fishing trips away from power?

You can solar charge that 12v battery at a rate equal to or greater than the draw for not alot of money.

[Evans, Marv]

Originally Posted by dad911

Kayak fishing trips away from power?

You can solar charge that 12v battery at a rate equal to or greater than the draw for not alot of money.

Ha! Ha! The slope get's steeper!!!

[red-beard]

Originally Posted by Pazuzu

You're welcome. I figured you wanted a down and dirty explanation, rather than a treatise on the inability of modern batteries to maintain power over time

You're welcome

[red-beard]

Vash, PM me your address or where you can receive a package.

[vash]

you wouldnt happen to have the stuffed squirrel, would you?!

[red-beard]

Originally Posted by vash

you wouldnt happen to have the stuffed squirrel, would you?!

LOL! Thank God, no.