Ok, so what did I do wrong? please :)

[kicker9898]

Sorry to come to the community with another question about wiring.

One of my pyle converters fried tonight after getting everything hooked up what I thought was correctly.

I have a negative ground feed coming from the 24V neg battery post to a bussbar, both converters 24V NEG wires are hooked into this grounding bar.

I have 2 fuse panels hooked to the 12V side of the converters, and these are grounded back to the 12V Neg side of the converters.

I have another fuse panel for accessories that I ran up front under the dash, my CB and stereo were hooked to it. I was having problems with them and finally thought to check the voltage with a multimeter, it was getting 24V. These radios were grounded to the chassis, not the negative on the main fuse panel.

I was trying to figure out what would cause that and realized that my negative battery connection to the buss bar was not hooked up. I hooked it up and fritz! there went one of my converters.

So, should I have grounded the 24V to the chassis instead of the negative battery terminal? What was causing 24V to go to what should be 12V fuseblock? Should the 24V feed not be grounded or should the converters 12V side not be grounded?

Jason

 

[DieselBob]

So, should I have grounded the 24V to the chassis instead of the negative battery terminal? What was causing 24V to go to what should be 12V fuseblock? Should the 24V feed not be grounded or should the converters 12V side not be grounded?

Having the 24 volt side grounded to either the battery or chassis is ok because the negative battery cable goes to a bolt on the frame for ground anyway. It sounds like the problem is with the ground potential. There are 2 basic ways to change from a higher voltage (24volts) down to a lower voltage (12 volts). You either lower the positive voltage potential or raise the negative potential. If I read your post correctly you ran a 12+ lead from the converter to a fuse panel under the dash for the CB and radio but used a chassis ground instead of running a lead back to the 12GND terminal on the converter. I suspect the problem is that the 12 volt accessories need to be connected only to the 12+ and 12GND terminals on the converters and that the 12GND should not be connected in anyway to the chassis. This keeps the 24volt and 12 volt circuits completely separate. Thats my best guess and no, I didn't stay at a Holiday in Express last night...

 

[kicker9898]

Having the 24 volt side grounded to either the battery or chassis is ok because the negative battery cable goes to a bolt on the frame for ground anyway. It sounds like the problem is with the ground potential. There are 2 basic ways to change from a higher voltage (24volts) down to a lower voltage (12 volts). You either lower the positive voltage potential or raise the negative potential. If I read your post correctly you ran a 12+ lead from the converter to a fuse panel under the dash for the CB and radio but used a chassis ground instead of running a lead back to the 12GND terminal on the converter. I suspect the problem is that the 12 volt accessories need to be connected only to the 12+ and 12GND terminals on the converters and that the 12GND should not be connected in anyway to the chassis. This keeps the 24volt and 12 volt circuits completely separate. Thats my best guess and no, I didn't stay at a Holiday in Express last night...

Yep, that is correct. I wondered about the 12v and 24v ground both to the chassis being a problem. I still can't figure out though why the converter fried. I guess I need to educate myself more thoroughly on 24v wiring. Is there a good source of info on this?

 

[eagle4g63]

I am not 100% sure with using a converter.......however I run 2 alternators on my truck(deuce) and have BOTH grounds running straight to frame. the only thing I keep separate is the +(positive) wire. I am running a 12 volt battery and the 24 volt batteries........all the 12 volt accessories run flawless and they are grounded to the truck chassis just like all the 24 volt grounds.

What kind of truck are you working with, might be cheaper to just add a 12 volt alternator and have an easier time with things.

 

[kicker9898]

HI Eagle, I have a 923A2. I have thought about the 12v alternator route. However, I better with wires and electronics than wrenches. Of course, I did just fry a converter so maybe I'm not that great with either LOL.

I thought that the converter route would be easier, faster and cheaper for now. I do want to add an alternator later on, but also not sure where to put that extra battery. The box is pretty full now with 4 in it already. Plus I think that this setup once I get it worked out will be about all I need to cover my 12v needs for now. I did purchase a Pulsetech 24/12 box I'm also going to hook up for small 12 volt loads. This should give me plenty of juice for 12 and 24 volt.

Which brings up one more question...how much juice for accessories and stuff can we pull from these trucks before we start to approach the safe limit. What is the alternator on the A2's rated?

 

[eagle4g63]

Both my alternators are CIVI AC/Delco units.......the 24 volt one is a 60 amp and the 12 volt......not sure it is just a regular GM alternator(60-100amp I think). One way around the battery thing.......by chance is your batteries like the ones in the deuce.....HUGE things that take up a bunch of space........I am able to put 3 nice off road batteries in the same spot the 2 military ones are in. You can also use a nice small lawn mower battery for your 12 volt side.....I ran that way for a year in my older deuce.....very easy to find a spot for a very small battery, as I originally just used it for a CB, cell phone charger and a police spot light.

 

[Warthog]

Can you draw out a diagram of how you wired your converters? And wher exactly you tapped into the batteries. Pics would also help

 

[MarcusOReallyus]

Can you draw out a diagram of how you wired your converters? And wher exactly you tapped into the batteries. Pics would also help

Bingo. This is what is needed to really understand what you are doing.


Inverters & converters are a different animal, and the whole concept of "ground" is a rich source of confusion for a lot of people.

Unfortunately, "ground" to most people means "attached to the frame somewhere".

That's not always true.

In the case of inverters and converters, it's often not true.

 

[cranetruck]

I think this is a good thread, but some diagrams are needed to understand each hook-up, perhaps user manual do's and don'ts would help.

 

[cranetruck]

For small power demands, a few amps, I use what I call Point of Load (POL) converter(s). image shows an example where 12 volts was needed for a temperature gauge. It's homemade and built from parts laying around on my work bench. Being a series type converter, ground is not a problem, same on input as output.

 

[kicker9898]

Sorry for the sloppy writing, let me know if there are questions. The top line is just going to the 24V bussbar, it didn't scan but I don't have anything hooked to it now anyway.

The battery connections are on the batteries used for the slave cables. Yes, I think that I am confused about the concept of ground lol, I would love it if someone could point me to a good source of DC electrical primer and theory. I've searched and looked but haven't come up with much. My plan right now is to run the 12V acc grounds back to the 12V neg bar on the fuseblock. Maybe someone can tell me if I need to also unhook the 24V ground to the battery...thanks for all the suggestions it is much appreciated.

BTW, I didn't show fuse locations, but there is an inline fuse between the main battery connection and the distribution block. Each feed out of the D-block is fused, the converters are fused of course and then more fuses at the 12V fuseblocks. Also have a disconnect switch between the battery and inline fuse.

Jason

 

[cranetruck]

The CB ground must be connected to the converter grounds, not vehicle ground as shown, since you are keeping the converter outputs "floating" (=separate from vehicle power).

You may need to find a way to ground the converter outputs, there may be issues with the CB antenna, which needs a good "ground plane" if you don't.
What is the converter model number(s)?

 

[212sparky]

Re: Ok, so what did I do wrong? Help please

You may hanger an issue paralleling you're outputs to the 12 volt fuse box. When I bought mine it said not to do that. Once the magic smoke comes out it does not go back in:banghead:

 

[goldneagle]

The easiest way to do it is with a VANNER Battery Equalizer. The 12 volt and 24 circuits share the same ground so there is no conflict. Look up Battery Equalizer on this site and you will find plenty of info on it. I use them on all my trucks! Available cheap on Ebay. Just have to be patient for the right priced one to come up. Got a NOS one for $85 shipped!

 

[kicker9898]

You may hanger an issue paralleling you're outputs to the 12 volt fuse box. When I bought mine it said not to do that. Once the magic smoke comes out it does not go back in:banghead:

Darn it, I was hoping I could get it to go back in LOL. I was afraid of that

I had thought about the equalizer as well...may end up going that route. After all the work wiring this puppy though I think I will get another converter and try it again. I also will get another fuseblock to wire to each converter instead of parallel. The amplifier I am running is a kenwood 4 channel and it has 2 30 amp fuses which is why I tried paralleling the converter outputs.

The converters are Pyle 720 watt 24-12 converters, part number PSWNV720. Cranetruck, I think you are right on the CB...it was showing a very high SWR.

 

[MarcusOReallyus]

If you are using a converter which does not share ground with the vehicle (which is typical for converters), then you MUST make sure that ALL possible grounding points do NOT contact vehicle ground ANYWHERE. This is NOT optional!!!


That means you cannot use CB antenna that is grounded anywhere.




For what you want to do, go with the Battery Equalizer. Since you are doing a CB, you really need to share the vehicle's ground with your entire system.

Otherwise, you are just going to let the smoke out again.

 

[moving chicane]

My first guess was that the converter outputs being connected together on the positive side let the smoke out. You would need to have a diode on the outputs so they can't backfeed into each other. The isolated 12v neg bus bar is asking for trouble as well. I'm not well read on the requirements for ground planes and CB's, but on my setup everything DC negative is grounded to chassis. A good primer to DC systems is "The 12V Bible" http://www.amazon.com/12-Volt-Bible...&qid=1368920952&sr=1-1&keywords=12+volt+bible

 

[doghead]

How many amps of 12v power do you need?

 

[kicker9898]

How many amps of 12v power do you need?

I'd love to be able to get 100 amps. However, I probably need to scale that back, and maybe that is unreasonable without a dedicated 12 volt charging system.

 

[MarcusOReallyus]

I'd love to be able to get 100 amps.

However, I probably need to scale that back, and maybe that is unreasonable without a dedicated 12 volt charging system.

Do not pass go, do not collect $200. Go directly to a dedicated 12 volt charging system.


Better yet, think about why you think you need 100 amps. Audio amps running 1000 watts? Linear for the CB running in that range?

You probably don't need 100 charging amps - you can trickle charge a separate battery bank and get your 100 amps out of the batteries. You are unlikely to need a full 100 amps ALL THE TIME.


I once had a customer come in to the radio shop where I worked. His old-fashioned IMTS phone needed work. I got to chatting with him about his ham rig. He had a Toyota pickup with an extended cab, and behind the seat was a solid row of batteries. He was using that to power a 1500 watt linear on his 10 meter rig.

Factory single alternator.


Also, look into big capacitors to supply peak amps to the audio amps - you can scale down your supply system that way.