Voltage regulator

[osprey877]

I recently installed some LED strip lighting over my chart table. The strip comes in about a 10ft length and you can cut it to whatever length you want. It has a sticky tape backing that makes installation easy. Problem is that when my batteries are full or the charger is on, the batteries are at close to 14 volts and the LED's run hot. Hot enough that the mounting glue melts and the strip won't stay stuck to the bulkhead. I gather what I need is a 12 volt voltage regulator that will ensure the output voltage is exactly 12 volts, no more, no less. I have looked on line and there seem to be hundred's of models available, ranging in cost from $1.00 to $100.00. Can anybody recommend a specific regulator that will work, hopefully cheap?? Also, should I just put the regulator on the LED supply line immediately ahead of the lights so it only need to handle 1 or 2 amps of current, or is it better to get a 30 amp version and run the entire DC panel through a regulator??

Thanks again.

[john61ct]

just run what needs it, 12.5 rather than 13.8

Look at this on eBay http://www.ebay.com/itm/141988344308

Samlex also good, http://www.ebay.com/itm/162552286531

MasterVolt is pricey.

[osprey877]

I was hoping for something cheaper. What about something like this:
https://www.ebay.com/p/Dc-dc-12v-24v-to-6v-5a-Power-Converter-Regulator-Module-Step-Down-Adapter/552314722?iid=292144010185

Anybody else having same problem??

[john61ct]

That goes down to 6V, and 5A wouldn't power many strips anyway.

Other way is get a good charger where you can adjust the voltage.

Not cheaper but more generally useful.

[osprey877]

I have a good charger. The charging voltages are matched to the battery requirements and exceed 12 volts. The batteries when fully charged are putting out close to 13.5 volts. I need to step that down to 12 for the led lights only. There must be a simple and cheap solution?

[john61ct]

There should be a huge difference between the circuit's voltage while the charger is running, as opposed to when it's not, even when the bank is full. The former may be a problem, the latter should not be.

I didn't mean your charger is bad, just that few allow you to tune the voltage setpoint, and that's real handy in a charger for futureproofing.

Close to 14V means what? At what level do you see the problem? How many amps throughput do you need?

Shore power AC to adjustable DC power supply in the 5-8A range usually go for $40-80 secondhand, DCDC is a much smaller market so should cost more.

But search as mentioned on eBay, Amazon, look at Mouser etc, lots of cheap stuff worth trying, but decent quality at higher amp levels is likely going to cost more than a family going to McDonalds for dinner.

[denverd0n]

Cheap buck-boost converters are available on ebay. I have bought and used several in various electronics projects. Here is an example...
DC-DC Boost Buck adjustable step up down Converter XL6009 Module Solar Voltage | eBay

LED lights tend to be very forgiving of lower voltages, though they will not be as bright. I have a 12 volt rated LED indicator light that I have been powering off of a 9 volt wall wart for more than two years now and it is just fine. As you have observed, they can get quite hot if you run them with more than the rated volts.

The thing you need to know is how many amps your LEDs require. If it is only one string of lights then probably not much. My guess would be a couple of amps at most. Very possibly less than that. Voltage regulators are cheap and easy to make, but the more amps you want it to be able to handle, the more expensive it will be. As such, you don't want to get a 20-amp converter if you are never going to run more than a couple of amps through it.

Good luck.

[Colin A]

I have had good luck with Mean well looks they offer a few that may work

http://www.mouser.com/ProductDetail/...7ugwvHpA%3D%3D

[donradcliffe]

Here is a typical linear regulator--you should mount it on a heat sink, and the heat generated is a function of the difference between the input and output voltage.

http://www.mouser.com/ProductDetail/...252bDuz0dX8%3d

[john61ct]

That's just 1 amp!

I agree Mean Well is a good mfg, if 6A isn't enough they may have a bigger capacity line.

[masonc]

Since the load is constant, you could put a resistor
in line. 2 ohms 15W should work.

[osprey877]

Originally Posted by masonc

Since the load is constant, you could put a resistor
in line. 2 ohms 15W should work.

Will that still work if the voltage varies from 12 to 14 volts? I only want a voltage drop when the supply is more than 12 volts.

[john61ct]

Look at this on eBay http://www.ebay.com/itm/152592022511

[belizesailor]

Marine Beam also sells one.

[hellosailor]

A resistor won't help. The typical LED "strip" actually has a dropping resistor at each LED or string of 3 LEDs. As the supply voltage goes from 14.4 (engine) to 12-ish, the voltage after the resistor will drop as well.

And that's a problem with regulators, too. They all consume come voltage, often 1.5 volts, so a regulator that provides a solid 12 from 14.4...may only provide 10.6 from a 12v source.

You need to find out exactly what your LED strip is, whether it is regulated or just uses resistors or not, and how much amperage it needs to be fed. It ain't rocket science, but to make the LEDs reliable, you do need to do the math and find out the specifics they need.