Running electronics without the brick

[Sunking]

Power bricks today are really simple regulated DC Power Supplies. They just supply a fairly precise Voltage up to some amount of Current. I have a DC Supply that is adjustable from 5 to 30 volts up to 50 amps. It does not care what it is connected to, all I have to do is match the Voltage and ignore current because I have more than will be required by any device.

What I am driving at is all you have to do is match the Voltage and supply the maximum amount of current your gizmo uses. It can be done with solar and a few components about $4 worth. No the problem is how the heck you are going to be able to supply a dynamic power from a solar panel? One would think if you needed say 14 volts @ 3 amps all you need is a 50 watt panel. Wrong Dead wrong. A 50 wat panel only puts out 50 watts for a few minutes around noon. What do you do in the morning or afternoon when the panel can only generate 25% of its rated power.

How do you get around that? That is the problem you have to solve. Extremely easy to do, but expensive and impractical, you use a 250 watt panel for a 50 watt device. But even then you are limited to only bright sunny days for a few hours around noon. What do you do for the other 18 hours of the day?

[paulgareau]

Power bricks today are really simple regulated DC Power Supplies. They just supply a fairly precise Voltage up to some amount of Current. I have a DC Supply that is adjustable from 5 to 30 volts up to 50 amps. It does not care what it is connected to, all I have to do is match the Voltage and ignore current because I have more than will be required by any device.

What I am driving at is all you have to do is match the Voltage and supply the maximum amount of current your gizmo uses. It can be done with solar and a few components about $4 worth. No the problem is how the heck you are going to be able to supply a dynamic power from a solar panel? One would think if you needed say 14 volts @ 3 amps all you need is a 50 watt panel. Wrong Dead wrong. A 50 wat panel only puts out 50 watts for a few minutes around noon. What do you do in the morning or afternoon when the panel can only generate 25% of its rated power.

How do you get around that? That is the problem you have to solve. Extremely easy to do, but expensive and impractical, you use a 250 watt panel for a 50 watt device. But even then you are limited to only bright sunny days for a few hours around noon. What do you do for the other 18 hours of the day?

Well like I said, the modem uses 12v@1amp, maximum. I run it for maybe 10 hours per day when I need it, so 120 watts per day. My battery is 100ah. My solar panel is 160 watts, so on a good day I'm generating maybe 400 watts. Seems like there's no problem to me.

[Logan5]

I doubt that modem does not uses 1 amp @ 12 volts, it will use less than 1amp, could be 800 ma could be as low as 500 ma. The AC brick is always rated over what is needed by the device. The question is by how much? You can find out with your multi meter.

[SunEagle]

I doubt that modem does not uses 1 amp @ 12 volts, it will use less than 1amp, could be 800 ma could be as low as 500 ma. The AC brick is always rated over what is needed by the device. The question is by how much? You can find out with your multi meter.

You are probably correct the true load will be less than that 1 amp rating on the Brick.

Although at that low of an amp reading I doubt his meter is calibrated to be that accurate to matter.

[paulgareau]

I doubt that modem does not uses 1 amp @ 12 volts, it will use less than 1amp, could be 800 ma could be as low as 500 ma. The AC brick is always rated over what is needed by the device. The question is by how much? You can find out with your multi meter.

I did say 12v@1amp /maximum/... Not really a concern because I have plenty of battery and solar panel capacity anyway - if I get more runtime it's just an added bonus.

[Mike90250]

my only concern is that the 12V gear may not like the >14V when the batteries are charging hard. Routers are not automotive gear, and would not be expecting a wild voltage input.
However, my linksys has a 12V wart, and internally regulates that down to +5 for everything !! So it depends on the heatsink capacity, if it can handle a couple more watts on the regulator chip

[SunEagle]

my only concern is that the 12V gear may not like the >14V when the batteries are charging hard. Routers are not automotive gear, and would not be expecting a wild voltage input.
However, my linksys has a 12V wart, and internally regulates that down to +5 for everything !! So it depends on the heatsink capacity, if it can handle a couple more watts on the regulator chip

That was my concern. Sometimes that "brick" has more in it then just an AC to DC circuitry. There could be a filter, voltage regulator, among other do dads to make that electronic load happy.

[Logan5]

Devices I have powered with a battery directly through a LVD are. Linksys routers all but 5v models. The original Atom 12v laptop. Supersonic 11" TV, Insigna 15" TV, D-link wireless and wired routers and switches rated 12v. Using a step up or in my case a step down from 24v, I have run almost everything else. If you have any concerns employ an in line voltage regulator, that should level out the peaks. I have an Ubiquity Rocket, it can accept input from 10 to 32 volts.

[Mike90250]

Devices I have powered with a battery directly through a LVD are........

NO. If you are using any sort of a regulator, you are NOT powering DIRECTLY . (shakes head)

[Logan5]

yes, my reference is to the voltage of the circuit, the LVD device should not alter the voltage, only monitor it. Either way, I would not connect any device directly to the battery bank w/o a LVD.