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RogerDat

LED 12 VDC lighting problems.

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RogerDat

Pay pal is a deal breaker for me as they will NOT secure my account, nor maintain a password that will work.

The circuit looks OK except where to get the relay from here?

Edited by RogerDat

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Paul

There is a reason he listed a "3-stage" charger. This is also why I mentioned Iota, or similar chargers. Deep cycle batteries need to be charged by a specific type of charger, NOT a typical automotive battery charger. While you certainly can find other types of chargers online, this is an example of what you should buy, to best charge your battery, for longest service from it. 

 

http://www.iotaengineering.com/12vdc.htm

 

http://www.iotaengineering.com/iq.htm

 

 

Pay pal is a deal breaker for me as they will NOT secure my account, nor maintain a password that will work.

The circuit looks OK except where to get the relay from here?

 

Here is a relay that I use to power a system similarly. The difference being 230vac to 230vac, rather than 12vdc to 12vdc. Similar idea, though.

 

http://www.livingincambodiaforums.com/ipb/topic/4954-automatic-transfer-switch-from-mains-to-inverter/

Edited by Paul
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Woolf

Pay pal is a deal breaker for me as they will NOT secure my account, nor maintain a password that will work.

The circuit looks OK except where to get the relay from here?

 

 

this type of relay        any auto accessory shop

 

12-volt-automotive-relay-30-40-amp-23-26

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Paul

They would be called a 12volt lighting relay, in the US, Roger. Typically included with fog or driving lights kits. But, certainly sold separately as well. 

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Woolf

Be sure to get a relay with 5 terminals or there will not be a NC terminal

Edited by Woolf
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Woolf

Here is a relay  even delivered to your door

 

http://www.lazada.com.ph/waterproof-car-truck-auto-automotive-12v-80a-80-amp-spdt-relay-relays-5-pin-new-intl-2982145.html

 

 

Hmmm well long delivery time

 

Try an auto accessory shop

Edited by Woolf
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Oz Jon

There is a reason he listed a "3-stage" charger. This is also why I mentioned Iota, or similar chargers. Deep cycle batteries need to be charged by a specific type of charger, NOT a typical automotive battery charger. While you certainly can find other types of chargers online, this is an example of what you should buy, to best charge your battery, for longest service from it. 

..............................

 

Here is a relay that I use to power a system similarly. The difference being 230vac to 230vac, rather than 12vdc to 12vdc. Similar idea, though.

 

..........................

Right Paul - a 220VAC relay on the mains side or a 12VDC relay on the battery side achieves exactly the same result - it senses mains failure!

 

The advantages of the 12VDC solution are they are cheaper than 220VAC relays, readily available as auto spare parts and you don't need to get involved with potentially dangerous mains wiring.

 

As to the battery and charger - You are right that you need deep-cycle batteries and fairly complex chargers if you are running a solar/wind/off-grid system. That stuff is expensive!

 

I assumed that Roger only needed occasional battery back-up and that for most of the time his battery would be unused, fully charged and on float charge.  After an all-night back-up session, I assumed that the battery would be about 50% discharged. Then a relatively cheap 3-stage charger would re-charge it back up in 10-12 hrs, ready to do the whole thing again, if necessary.

 

I figure that an ordinary, relatively cheap, big 12V car starter battery (or a couple of smaller ones in parallel) would do that job fine.*

 

Roger - There are plenty of 3-stage charger options on the internet (Ebay. etc) and I suspect that the bigger auto spare parts shops in the Phils would have such products. Sorry, but I don't have current experience with Phils shopping to give you specific supplier advice - other LinC members may be able to help you though.

 

Cheers!

 

* I assumed your essential load was about 5 Amps, so a 100AH @ 20hr rate battery needed - that's a big car battery!

For lesser essential load you could use a smaller, cheaper  car battery (about 50-70AH is typical for a medium sized car battery)

Edited by Oz Jon
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RogerDat

marker page 12. Time to buy.

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Paul

marker page 12. Time to buy.

 

Um, what?

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thebob

How far is your battery from your lights?

 

Voltage drop in 12V lines is considerable unless they are huge. It is probably cheaper to use an inverter and run mains voltage to remote lights. 

 

You will get "much" better efficiency using 2 batteries and running a 24V system, then you can run much lighter wiring.

 

LED's aren't 12V devices. Generally they have a forward voltage drop between about 1.2V and 3.8 Volts depending on colour.

 

"White" LED's are usually between 3.4 and 3.8 volts. Current limiting is where most efficiency is lost. Automotive style "bulbs" are pretty inefficient, but they don't need to be.

 

I'd guess that most of your power is being wasted heating thin 12V cable.

 

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Cipro

V=IR

 

The drop will depend on how big the load actually is, or more intuitively, the importance of the wire size is dependant on what part of the total system resistance is in the wires. Generally some LEDs wouldn't be much of a load. 

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thebob

 5W / 12V = .42 Amps

 

Low Voltage Power Drop Charts

 

Note: for both AC and DC low voltage, generally the maximum acceptable voltage drop is 10%. The below charts assume this.


                    24 AWG    22 AWG      20 AWG       18 AWG      16 AWG   14 AWG    12 AWG
DC 400mA  54 feet      85 feet         148 feet        216 feet      344 feet    549 feet    877 feet
 
 
Edited by thebob

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RogerDat

And where to get 220 volts during blackouts?

14/12 gauge wire. amp draw is 0.11 per 12 DC LED.

12 volt DC LED's are indeed 12 volt. I use auto type 3 light strips for night lights, so little amp draw.

4/5 watt is security lights.

 

Paul, marker page 12. Time to buy. This is my way bringing the post forward cause it is many pages back, took 10 minuets to find it.

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Oz Jon

LED's aren't 12V devices. Generally they have a forward voltage drop between about 1.2V and 3.8 Volts depending on colour. "White" LED's are usually between 3.4 and 3.8 volts. Current limiting is where most efficiency is lost. Automotive style "bulbs" are pretty inefficient, but they don't need to be.

 

Oh Bob!,

 

You and me both, trying to figure this lighting thing out.

 

We are both too Engineering/Technically oriented! - Lol!

 

I was thinking about 30cent (pea-sized things with wire legs) or higher powered $2? (postage stamp sized things) LED's too!

 

I'm pretty sure they are talking about the (rather expensive) retail LED lamps that are about the size and shape of traditional residential filament lamp bulbs or 12V LED array versions intended for the auto market.

 

The 12VDC or 240VAC rated ones must have some kind of current limiting/conditioning electronics built-in.

 

 

edit:

After a quick re-reading earlier posts, it strikes me (without enough evidence to be sure) that the battery plan is a bit of an overkill .... but that's better than under-providing! 

 

I'm reminded of an old Engineering adage - "any solution that works, is a good solution!" - Lol!

Edited by Oz Jon
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easydrifter

Just get a small inverter connected to your batteries and go AC all the way, get rid of the 12 volt lights and use 230 volt AC LED lights.

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