My 12 Volt DC Accessory Kit Installation

m715mike

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I recognize this topic has been covered at length, and I am very appreciative. I've spent a fair amount of time researching 12 volt-related threads and am very thankful for the collective information posted by members on this site. When it's all said and done, my goal for this thread is to consolidate the knowledge I've gained and showcase the installation in my truck.

Disclaimer. This is my first electrical modification to any vehicle ever. I am a novice (to say the least) and have enjoyed learning and planning so far. If the information in this thread seems very basic, that's because it is. If it is too basic for you, please feel free to check-out the pictures and move to the next thread.

What's going in? My wife had a custom 12 volt accessory kit made for me as a Christmas gift. It has three ports for cigarette lighters and four USB ports. There are two in-line fuse holders with 15 amp fuses and a toggle switch. It is built to look like the dash of a M35A2 and the port covers light-up like the dash.

Uses. The 12 volt accessory kit will primarily be used for a phone charger and a GPS unit. At this time, I do not plan to add other 12 volt accessories. But who knows, there may be a CB radio added in the future.

Other. I want all of the accessories controlled through a common switch. Also, I want to add a 24 volt back-up camera in the future (but that is a ways off).

The Plan. I'm using a 50 amp, 24 volt solenoid to switch the accessories. There will be a 50 amp in-line fuse between the batteries and the solenoid. From the solenoid, 24 volt power will go to a common busbar, which will facilitate future installation of the 24 volt camera. I decided to use a Pyle 24 volt to 12 volt converter for power at the accessory kit. There are a lot of options for this (battery equalizer, 12 volt alternator, center tap one battery, etc.), but I decided to go with the Pyle converter. Here is a (very crude) wiring diagram:

View attachment 12V DC Accessory Kit_Install.pdf

Materials. In addition to the custom 12 volt accessory kit, I will use the following materials:

CostComponentManufacturer / Part NumberVender (Item #)
$76 gauge in-line fuse holder, 80 amp maxMaxiDel City (78515)
1650 amp fuses (Quantity: 10)MaxiDel City (78504)
5624V DC Solenoid, 50 AmpsWhite-Rodgers # 70-117224-5Grainger (#6C030)
8Toggle Switch, SPST, 2 Conn., On/OffPower First # 2VLN5Grainger (#2VLN5)
15100 Amp common busbarBlue Sea Systems PN: 2315Amazon
45720 watts 24V DC to 12V DC converterPyle # PSWNV720Amazon
15Red and black 10 gauge wire (8 ft. each)N/AAutoZone (85700R / 85702B)
10Black 6 gauge wire (10 ft.)N/AHome Depot
31Grommets, wire connectors and ring terminalsVariousVarious
$203

The installation is planned for next weekend. I will post more pictures when the install is done. Also, assuming it works, I will post more information about the challenges and questions I had when planning (remember, this was completely new to me).

12V kit 1.jpg12V kit 2.jpg12V kit 3.jpg12V kit 4.jpg

Comments, criticism and questions are definitely welcome.
 
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Rusty nuts

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I basically wired mine the same way except instead of a toggle switch to energize the solenoid, I tied it into the main switch so I wouldn't accidentally leave the converter on.
 

rustystud

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I think your batteries are wired wrong in your diagram. The first battery positive goes to the second battery negative, then you take off the second battery positive to get your 24volts. Besides that it looks like a winner ! Blue Sea products are very good, and expensive ! Del City is also a very good company, I use them a lot .
 

m715mike

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I think your batteries are wired wrong in your diagram. The first battery positive goes to the second battery negative, then you take off the second battery positive to get your 24volts. Besides that it looks like a winner ! Blue Sea products are very good, and expensive ! Del City is also a very good company, I use them a lot .
Rustystud - Good catch, thanks! That was a classic copy/paste error on my part. I had it hand written correctly in front of me and just copied and pasted the first battery when drawing it on the computer. My apologies. I have gone back and corrected the original post.
 

m715mike

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I basically wired mine the same way except instead of a toggle switch to energize the solenoid, I tied it into the main switch so I wouldn't accidentally leave the converter on.
I thought about using the main switch but decided to go with a separate toggle switch. That way I can charge a cell phone without the main switch on.
 

maddawg308

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Great concept, I'll subscribe to this so when I can get back into MV ownership I can revisit this project...
 

steelandcanvas

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Great job and your first vehicle electrical project as well! The only thing that came to mind was the 50 Amp overkill, you most likely could have gotten away with 20 or 30 Amp supply current. But it's best to have it and not need it, than to need it and not have it.
 

oddshot

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Subscribed.

I've been planning the very same project for a while now. I already have the same 24/12VDC convertor you are using.

The only thing I would advise is to make sure of is that your alternator is putting out enough amps to charge the batteries AND supply all the 12VDC stuff you intend to install.
 

m715mike

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The only thing that came to mind was the 50 Amp overkill, you most likely could have gotten away with 20 or 30 Amp supply current. But it's best to have it and not need it, than to need it and not have it.

The only thing I would advise is to make sure of is that your alternator is putting out enough amps to charge the batteries AND supply all the 12VDC stuff you intend to install.
Guys, thanks for the comments! I agree -- this install is a bit of an overkill for a phone charger and a GPS. I don't plan to use 50 amps of supply current. I had fun learning and planning and, given the relatively small price difference for smaller components, decided why not go with the overkill!

I started working backwards. The accessory kit has two 15 amp fuses (12 volts * 30 amps = 360 watts), which is a pretty good fit for the Pyle PSWNV720 converter (24 volts * 15 amps of "continued power" = 360 watts). In theory, the Pyle converter can handle 30 amps of "surge power," and I plan to add a 24 volt back-up camera down the road. As such, I rounded up to 50 amps for the solenoid. The other components were chosen to handle at least that much power (if not more).

steelandcanvas - You hit the nail on the head. Who wants to just get by when you can go with overkill?

oddshot - Great point! That is a big reason why I plan to limit my 12 volt load. The alternator (or generator) says "60 amps, 28 volts". I don't know what it is actually putting out.
 

m715mike

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M35A2 Dash Light Covers

I love that cover idea....can we get some more detail about them?
eagle4g63 - Thanks for the PM to clarify. You wanted more detail on how the M35A2 dash light covers were used to blend-in/hide the rubber cigarette lighter cover.

The two USB charger ports on the right side of the accessory kit have "USB Charger 1016" stamped on them. I googled it and they look just like the first image that comes-up. The rubber cover on the USB charger port is just slightly smaller than the M35A2 dash light cover (I'm assuming it was not modified). Best I can tell, the M35A2 dash light cover was glued to the rubber cover with a small LED light in the middle.

There are no numbers on the three cigarette lighter ports on the left side of the accessory kit; however, their case and rubber cover looks just like the USB chargers.

Here are some close-ups:

IMG_0282.jpgIMG_0283.jpgIMG_0285.jpgIMG_0286.jpgIMG_0287.jpg
 

eagle4g63

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I see....that is a great idea. I've got some extra covers, I'll have to see if I can do that to the plug in my truck.

Thanks for posting the close ups. I haven't looked into USB plugs before(only for use on my computers) I take it in a vehicle they are just a straight 12v plug for charging? Might be a easier way for charging an MP3 player than using the cigarette plug with an adapter.....
 

m715mike

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I haven't looked into USB plugs before(only for use on my computers) I take it in a vehicle they are just a straight 12v plug for charging? Might be a easier way for charging an MP3 player than using the cigarette plug with an adapter.....
Correct. Our cell phone chargers plug into a USB port. In the house, we have adaptors that plug into the wall. Both of our civvy vehicles have USB ports.
 

m715mike

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The accessory kit is going in the truck today. The install begins with a 60 mile road trip to my buddy's fabrication shop in Pasadena, Texas. I have one more trick up my sleeve...

I'm headed out in a few minutes to warm-up the truck. More information and pictures will follow later today or over the weekend.
 

swbradley1

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You will want a 15 or 20A fuse on the input side of converter inline and as close to the battery where you acquire your 24VDC feed. Then a 30A on the output as close to the converter as possible.

This minimizes the change of a short to ground in the wiring releasing magic smoke.

Good looking setup.
 
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