Running electronics without the brick

[paulgareau]

Hi. First post.

I bought some land in NH last year and have set up three small solar systems for different purposes. My most recent is to run a DSL modem/WiFi router off a 12v 100Ah battery. Before I got the modem I figured I'd need the typical battery/controller/inverter setup, but since the modem has an AC->DC brick I thought I could leave the inverter out altogether. The output on the brick is 12v/1amp. So my question is can I just cut the cable to the brick and hook it to the load terminals on the charge controller, or should I go through a DC to DC converter/regulator between the controller and modem? I have a RCA AH765R Auto Adapter.

(I will add a vent to the box before connecting the solar panels for charging).

Thanks!
Paul

[Logan5]

Yes, forget the inverter. Most routers will run from 15 volts just fine. If your device is 5, 6 or 9 volts, use a simple step down from your 12 volt battery. If you find you need more AH, you will also need more array. battery choices is a second 12 volt battery wired in series and the appropriate step down from 24 volts or 2 X 6 volt batteries wired in series for a 12 volt NOM system. You must employ a LVD=Low Voltage Disconnect to your load, or risk your batteries. Don't forget a terminal fuse. also the battery looks like a dual purpose battery, not the best choice for your application. Get some plastic caps on those lead post.

[paulgareau]

Thanks. Would I still need the DC-DC converter to serve only as a voltage regulator or is that not necessary? (That was my main question actually). AH seem OK for now with the single battery, but will be even better when I have a panel hooked up - I only turn the modem on when I'm using it. The charge controller has an LVD on the load terminals. Battery is a deep cycle - $70 from WalMart - it was the best choice for my budget.

[littleharbor]

There are a lot of inexpensive charge controllers these days with 12 output and usb output jacks. This one is only $11.99 w/ free shipping. Charge controller usb .jpg

[Enejo Sulei]

Hello, do you know were i can get an instructional video for the the EP-Solar 30A 12/24V Charge controller. ViewStar Model: VS3024N.
Thanks for any assistance...

[smily03]

I do something similar at home -- my router is 12v and bridge runs 24v POE. They're both powered, along with a number of other low-voltage DC things) by a 150W power supply (which also charges a SLA battery.) DC power supply outputs 13v8, and so I have a couple of DC-DC converters : two 5v, one 3v3, one 12v, one 16v, and one 24v. (the last two being boost, the first 3 being buck.)

(In my case, the SLA battery is maintained by a PicoUPS 120.)

I would recommend trying to stick as close to the normal input voltage as possible just to be safe and make sure you don't shorten your equipment life.

All has worked fine for years now

[SunEagle]

There are a lot of inexpensive charge controllers these days with 12 output and usb output jacks. This one is only $11.99 w/ free shipping. [ATTACH=CONFIG]n327525[/ATTACH]

Be careful. You sometimes get what you pay for.

Most of those cheap charge controllers do not have high quality electronics or proper overcurrent protection for the "load terminals". Anything higher than 1 amp can cause them to overload or worse fry the entire CC.

[J.P.M.]

Be careful. You sometimes get what you pay for.

Or less. You want nice - you pay nice.

[littleharbor]

Understand. This was a randomly selected and my point being there are these options on CC's these days. Probably didn't need to bring up price.

[SunEagle]

Understand. This was a randomly selected and my point being there are these options on CC's these days. Probably didn't need to bring up price.

No problem. I didn't mean to pick on you.

I just wanted to warn some of the Newbees out there not to hook up their 1000 watt flood lights to the load terminals of the cheap CC units..

[paulgareau]

I don't know how the topic of charge controllers came up - I already have one, as mentioned and in the picture. Are you saying that instead of using my charge controller and a DC-DC converter/regulator, I should buy a charge controller that has a regulator built in? Just looking for clarification.

[paulgareau]

I do something similar at home -- my router is 12v and bridge runs 24v POE. They're both powered, along with a number of other low-voltage DC things) by a 150W power supply (which also charges a SLA battery.) DC power supply outputs 13v8, and so I have a couple of DC-DC converters : two 5v, one 3v3, one 12v, one 16v, and one 24v. (the last two being boost, the first 3 being buck.)

(In my case, the SLA battery is maintained by a PicoUPS 120.)

I would recommend trying to stick as close to the normal input voltage as possible just to be safe and make sure you don't shorten your equipment life.

All has worked fine for years now

Just to make sure I'm following, even though I'm using a 12v battery, you're suggesting using the DC-DC converter/regulator to lengthen equipment life?

[SunEagle]

Not necessarily. There are quality charge controllers that have rated "load terminals" that would work to directly power your modem with the battery voltage.

What we don't know is if your DSL modem requires anything unique that was part of the "brick" like filter circuitry or DC regulator.

[paulgareau]

Not necessarily. There are quality charge controllers that have rated "load terminals" that would work to directly power your modem with the battery voltage.

What we don't know is if your DSL modem requires anything unique that was part of the "brick" like filter circuitry or DC regulator.

OK that makes sense. I wouldnt expect my $10 controller to have rated terminals, and I'd expect the brick outputs a pretty clean 12v, so I'll go with the controller+regulator option. Appreciate the help.

[smily03]

It kind of just depends on the quality of your device; since batteries can run over 15v if you equalize, or below 11v when discharged, that could put extra stresses on the components, or cause unreliable operation. The little DC-DC converters are pretty inexpensive (I bought mine from pololu, but you can get cheaper ones from Amazon or Fleabay.)

[paulgareau]

It kind of just depends on the quality of your device; since batteries can run over 15v if you equalize, or below 11v when discharged, that could put extra stresses on the components, or cause unreliable operation. The little DC-DC converters are pretty inexpensive (I bought mine from pololu, but you can get cheaper ones from Amazon or Fleabay.)

Yep, already have a converter, as mentioned
Sounds like it's the way to go, thanks.