How do I regulate 24 volts down to 14.5 volts?

[468 NE Ga]

Hi y'all.I have a old cucv military blazer that has a 24 volt system.I want to install my Bone built 8 pill in it but I need to be able to turn the voltage down so I don't smoke it.The truck has two 100 amp alternators and two 1000 amp battery's so I think I have enough to run it,but I need to be able to adjust the voltage.Any help would be greatly appreciated.

468

[drdx]

Can you take a volt meter and tap into one of the batteries and confirm it is only 13.8 or whatever and just use that for power, or are the batteries 24v parallel? Either way, if you don't find a way, let me know. My local technician special ordered a step down deal for a local with a 24 volt vehicle and the guy never picked it up. I'm positive he'd love to sell it. It is made by a major brand, like astron or someone, but I can't recall at the moment, but it is new in the box and was there last time I stopped in.

Better yet, contact a sponsor on here, as they would greatly appreciate the business.


-drdx

[468 NE Ga]

Yes I could just tap into one battery and get normal voltage,but the amp is made to run up to 20 volts.I would like to be able to take advantage of the higher voltage when I need it,but run it around 15 volts when I don't.So I would like to be able to adjust the voltage.Will the unit you were talking about allow me to adjust the voltage?

[dragline]

sounds good, 15 volts cruising and just crank up the knob to 20 volts and squash some ducks!!!

[Foxhunter]

Couldn't you use one of the big external voltage regulators to adjust the volts down ?

(oop---can't link to where I was going to)

[drdx]

Yes I could just tap into one battery and get normal voltage,but the amp is made to run up to 20 volts.I would like to be able to take advantage of the higher voltage when I need it,but run it around 15 volts when I don't.So I would like to be able to adjust the voltage.Will the unit you were talking about allow me to adjust the voltage?

This unit is a fixed one I think and it's probably only a 20 amp deal. How big is your amp? I know that your amp is rated up to 20 volts, running it at that will probably shorten its life and only give you minimal signal strength increase, something it looks like you're probably aware of. If you do the high voltage deal, make sure to have a separate supply for the radio that is a little tamer, like 14 volts or so.

-drdx

[468 NE Ga]

Couldn't you use one of the big external voltage regulators to adjust the volts down ?

(oop---can't link to where I was going to)

I tried to find one in the area in which I live but had no luck.Do you know of a place on line that would sell something like that?

[468 NE Ga]

Yes I could just tap into one battery and get normal voltage,but the amp is made to run up to 20 volts.I would like to be able to take advantage of the higher voltage when I need it,but run it around 15 volts when I don't.So I would like to be able to adjust the voltage.Will the unit you were talking about allow me to adjust the voltage?

This unit is a fixed one I think and it's probably only a 20 amp deal. How big is your amp? I know that your amp is rated up to 20 volts, running it at that will probably shorten its life and only give you minimal signal strength increase, something it looks like you're probably aware of. If you do the high voltage deal, make sure to have a separate supply for the radio that is a little tamer, like 14 volts or so.

-drdx

The amp is a 8 pill so it will draw between 140 to 200 amps I think.As far as the radio goes I will just hook it to one of the battery's so it will not get the 24 volts

[Red Warrior]

Search for DC to DC converter on Google.

[Red Warrior]

Here is one from EBay for $65.

http://cgi.ebay.com/Astron-N2 ... 335bf427b1

[468 NE Ga]

Here is one from EBay for $65.

http://cgi.ebay.com/Astron-N2 ... 335bf427b1

Thanks for your suggestion but looking at the description of the converter it will only handle 10 to 24 amps.A 8 pill amplifier is going to draw way more than that.I need something that will handle up to a 200 amp draw.

[Foxhunter]

Couldn't you use one of the big external voltage regulators to adjust the volts down ?

(oop---can't link to where I was going to)

I tried to find one in the area in which I live but had no luck.Do you know of a place on line that would sell something like that?

Yes Fatboy makes them, you'd have to Google them. Here below will be a short older CBRT thread link where someone was asking about them. Basically it looks like they're used in similar situations to yours. People buy large aftermarket alternators and need to either cut down the voltage or make it fully adjustable. Sort of like a mobile version of a variac and also having the ability to handle high currents. I don't see the current ratings on them, but there are a few models with matching prices $100-$200. The mobile car audio installers have been known to use them also, as some of those guys get into huge power needs as well. So going to Fatboy's website might not be the only game in town, you'd have to check.


The DC-to-DC converters are commonly used on marine (boat) and construction heavy equipment machinery, often some of the DC systems they'll be using will be 24VDC-48VDC and they can't always install common consumer electronics in them without some sort of DC-DC converter to drop the voltage. Otherwise all the 12V stuff gets fried. So once again, there's the same problem you have. Getting a decent DC-DC converter at a reasonable price would be a trick, the higher current ones aren't cheap. I've looked into all this two years ago. Without having gone back and looked, I've seen 50A peak and 40A continuous and they were fairly expensive. I just can't see it, but who knows what you're budget is.


If someone just wanted plain "voltage drop", they could easily hook the amp to a pair of fairly long-length power leads (like a set of spare welding cables laying around) and you'd see a drop at the other end. For instance you might have 24VDC at the input end, and if the pair of cables are lengthy, you'd see maybe 20VDC at the load end. And under load, the voltage would drop a bit more maybe 16-18V who knows. I did it with a 24VDC power supply and got it to 20V on the load end, just playing around but it worked. All depends on length of lead and cable diameter. Basically the net effect would be a calculated tuned-length set of power supply lines. Sort of intentionally doing what others in different situations would try and avoid. By the way, I'm not suggesting it. Just felt like writing it. Well it's a few things to think about.

Check the comp guys sites for the external adjustable regulators.

[468 NE Ga]

Thanks for the info foxhunter.I am going to contact fat boy and see which one I need as they offer a few different ones.The prices didn't look to bad either.When I get this thing finished maby DX will allow me to get a radio check from you,and you can let me know how it sounds .Take care

[drdx]

Maybe I'm odd, but I'm not a volter. I just double the pill count when in doubt. It is much simpler and last forever. It's kinda like saying "do you want to generate 500hp with a turbo'd built v6, or a mildly modded and naturally aspirated v8? Both have their pluses. Really tho, that 8 pill at stock voltage will give you a signal that is reallly reallllly close to what it would be volted. If volting DOUBLED its output, that's less than a pound. You see more change than that just by rolling around, as location is everything. You'd probably gain more by addressing other areas, like the antenna system- coil loss reduction, placement, etc.

-drdx

[kzhorse]

would a motor maul work?

[Triple_8]

A couple of questions, first and I may have the answer, for almost free.. it may cost you the most $5-$10.............. what type truck? and what year...and size motor....... , diesel or gas? Stock alternator............. thanks,,,,,,,, post those questions, and I will tell you how to do it......, I did it to my truck, 03 F350, Diesel, stock alternator,,,,,,, I get it to around 15-15.89,,,,,,,,,, and no more, than 15.99..nothing 16 and over......stock electrical system, does not like 15.99 or higher,,,, but anyways I will await your response and then give you the cheap solution!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

[468 NE Ga]

The truck is a 1985 Chevy blazer with a 6.2 diesel.It has two stock 100 amp delco alternators.The truck came from the military.

[-=PEAKABOO=-]

What should he do when the insulation on the wire starts melting?

Couldn't you use one of the big external voltage regulators to adjust the volts down ?

(oop---can't link to where I was going to)

I tried to find one in the area in which I live but had no luck.Do you know of a place on line that would sell something like that?

Yes Fatboy makes them, you'd have to Google them. Here below will be a short older CBRT thread link where someone was asking about them. Basically it looks like they're used in similar situations to yours. People buy large aftermarket alternators and need to either cut down the voltage or make it fully adjustable. Sort of like a mobile version of a variac and also having the ability to handle high currents. I don't see the current ratings on them, but there are a few models with matching prices $100-$200. The mobile car audio installers have been known to use them also, as some of those guys get into huge power needs as well. So going to Fatboy's website might not be the only game in town, you'd have to check.


The DC-to-DC converters are commonly used on marine (boat) and construction heavy equipment machinery, often some of the DC systems they'll be using will be 24VDC-48VDC and they can't always install common consumer electronics in them without some sort of DC-DC converter to drop the voltage. Otherwise all the 12V stuff gets fried. So once again, there's the same problem you have. Getting a decent DC-DC converter at a reasonable price would be a trick, the higher current ones aren't cheap. I've looked into all this two years ago. Without having gone back and looked, I've seen 50A peak and 40A continuous and they were fairly expensive. I just can't see it, but who knows what you're budget is.


If someone just wanted plain "voltage drop", they could easily hook the amp to a pair of fairly long-length power leads (like a set of spare welding cables laying around) and you'd see a drop at the other end. For instance you might have 24VDC at the input end, and if the pair of cables are lengthy, you'd see maybe 20VDC at the load end. And under load, the voltage would drop a bit more maybe 16-18V who knows. I did it with a 24VDC power supply and got it to 20V on the load end, just playing around but it worked. All depends on length of lead and cable diameter. Basically the net effect would be a calculated tuned-length set of power supply lines. Sort of intentionally doing what others in different situations would try and avoid. By the way, I'm not suggesting it. Just felt like writing it. Well it's a few things to think about.

Check the comp guys sites for the external adjustable regulators.

[-=PEAKABOO=-]

Why not just have your technician that built the amplifier change out the 2879's for something rated at 28 volts? Thats how I roll.