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Thread: Power for accessories

  1. #1
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    Cool Power for accessories

    First let me state that I am electrically challenged. I understand the basics, but once it gets complicated, I'm lost. I can hook up a stereo or amp without many issues but do not planning on installing them in this car. I'm getting near the point of adding some electrical options not included with the Factory Five kit. I am going with FF's heater and wipers. The motor will be a 347 FI if that matters. I will be adding heated seats, a USB charger, some foot well and trunk lights, cruise control and possibly foot well air vents.

    I don't want to have a mix of different in line fuses or any jumpers to the existing fuse box. I want a nice, clean, and professional install. Is an extra fuse box connected to a "bus" bar a good option? If so, how would it know when to switch on rather than being HAAT (I just learned that term from this forum).

    Terry

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    Member shackf16's Avatar
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    Terry, what are you using for your chassis wiring harness? A lot of guys use a Ron Francis harness that already has a "feed wire" for many of the items you listed, but certainly not all. You could always contact them directly and they can fabricate a harness that has all of the things you are looking for. Another (cheaper?) option is to add on a 6-8 circuit secondary fuse box that is powered by a relay to be HIR (Hot in Run). That is what I'm doing and takes a little more work to get set up. I have a 6-circuit Blue Seas fuse panel that powers my heated seats, aux power plug, daytime running lights, ABS (the HIR 10-amp feed) and reverse light. The running lights (LED) and reverse light draw so little current I could have tied them into the same circuit and left an empty slot for future growth.

    You can activate the coil part of the relay that powers the fuse panel with a HIR wire from the ignition switch or some other source on the main fuse panel, but the main relay feed can be powered directly from a HAAT source. When the relay gets activated by the HIR wire, it closes the circuit between the battery feed and makes it HIR. The relay needs to be rated for sufficient amps to power the entire 2nd fuse panel. I have an 80-amp relay but only have about 45 amps being used.

    If you have time and are confident in your plans, then a custom harness from Ron Francis would be the least effort, but don't be afraid of adding a 2nd fuse panel either. Do some homework and ask lots of questions, and you'll be fine.

    Cheers,
    Shack
    Mk 3.1, "Stock" 306 w/ Trickflow Top End, 4-into-4 headers, full MSD ignition, T-5, 3-Link, Ron Francis wiring all around, Autometer Ultralights, RT turn signal and gas pedal, NorthRaceCars A/C, heated seats, Hydroboost PS/PB (Brembo/Baer 13" combo), ABS, SAI mod, VPM sway bars, dual roll bars, dropped trunk, center console, APE hardtop, trick camera setup...too much time and $$$...one day she'll get painted! Delivered 8/05, first start 3/16/06, Go Kart 6/1/06, Titled & registered 7/21/08.

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    Senior Member CraigS's Avatar
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    This is a common problem w/ a couple of solutions. Used to be we would just add a few extra leads to the firewall solenoid + post. Sometimes people would try to do that at the starter but that gets messy real quickly since the starter stud is short and there isn't a lot of extra room there anyway. My preference is something like this.
    https://www.delcity.net/store/ATO:AT...08167.h_808168
    Power comes in to the terminal near the middle and goes out via a fuse at one of the six terminals on the side. Here are some relays to use per Shack's idea.
    https://www.delcity.net/store/5-Pin-..._73576.h_73663
    There are a couple of other suppliers also so look around the web.
    FFR MkII, 408W, Tremec TKO 500, 2015 IRS, DA QA1s, Forte front bar, APE hardtop.

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    Senior Member edwardb's Avatar
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    You could use an additional fuse panel or have something custom made. But IMO not necessary. What you're describing isn't complicated using the standard kit supplied Ron Francis harness:

    FF's heater and wipers = standard circuits available.
    The motor will be a 347 FI if that matters = EFI power and electric fuel pump circuits available as standard.
    I will be adding heated seats = with EFI, you won't need the choke circuit, so use to power the seats.
    USB charger = use the radio circuit since you said you won't be installing one.
    some foot well and trunk lights = courtesy lights are standard (twist of the headlight switch). You can add a wire to use that circuit also for the trunk light, or tap of one of the other existing lighting circuits for the trunk. Especially if you use LED lighting, very low current draw.
    cruise control = depending on current draw, could add to an existing circuit. Or create a new one.
    possibly foot well air vents = same as cruise.

    For added circuits (I typically have a couple too) I like to use these: https://www.delcity.net/store/12V-Au...98669.h_198850. You can wire them directly to a battery source (e.g. bus bar) if you want powered all the time. Or run through a relay if you want them switched via the ignition switch.
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  7. #5
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    Thanks Shack, that is exactly what I needed. Yes, I'm using the standard RF harness. Where did you mount your fuse panel?

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    Thanks Craig. That is what I'm trying to avoid. I don't want to have a rat's nest of wires going through the engine bay to a + post.

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    Quote Originally Posted by edwardb View Post
    You could use an additional fuse panel or have something custom made. But IMO not necessary. What you're describing isn't complicated using the standard kit supplied Ron Francis harness:

    FF's heater and wipers = standard circuits available.
    The motor will be a 347 FI if that matters = EFI power and electric fuel pump circuits available as standard.
    I will be adding heated seats = with EFI, you won't need the choke circuit, so use to power the seats.
    USB charger = use the radio circuit since you said you won't be installing one.
    some foot well and trunk lights = courtesy lights are standard (twist of the headlight switch). You can add a wire to use that circuit also for the trunk light, or tap of one of the other existing lighting circuits for the trunk. Especially if you use LED lighting, very low current draw.
    cruise control = depending on current draw, could add to an existing circuit. Or create a new one.
    possibly foot well air vents = same as cruise.

    For added circuits (I typically have a couple too) I like to use these: https://www.delcity.net/store/12V-Au...98669.h_198850. You can wire them directly to a battery source (e.g. bus bar) if you want powered all the time. Or run through a relay if you want them switched via the ignition switch.
    Thanks. I'm liking the delcity.net website a few of you have suggested. I can spend a lot of time browsing there.

    I've never heard of the auto reset circuit breakers. It is an interesting alternative.

  10. #8
    Senior Member CraigS's Avatar
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    "I've never heard of the auto reset circuit breakers. It is an interesting alternative."
    Yes but be careful how you use them. One caused 2 yrs of problems for me. I know it seems too simple after I figured it out but....anyway, there was one in the circuit powering my radiator fan. I have a front mount battery and a power lead coming from it to provide the main fan power. Of course the fan would only shut off at the worst times. I finally got lucky. Was working in the engine area on the shoulder after the fan died. Checking this and that and I happened to hear a click and the fan started up. Turned out there was an auto reset breaker in that power lead all nicely camouflaged by by the harness split loom.
    FFR MkII, 408W, Tremec TKO 500, 2015 IRS, DA QA1s, Forte front bar, APE hardtop.

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    Senior Member Big Blocker's Avatar
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    Terry,

    The 6-circuit Blue Seas fuse panel is a real nice piece of equipment and easy to wire into your existing system(s).

    IF you decide to use self re-setting circuit breakers, put them in an accessible location.

    Every fuse panel needs a master fuse to protect it from "total load".

    Power Buss-bars are also a good choice if the stud on the starter relay / solenoid starts to get too crowded. This is true for Ground Buss-bars too.

    IF you "gang" grounds together, remember that many 18 Ga wires banded together (for convenience) need a 12Ga to ground.

    Grounds can be one size smaller than the power wire feeding the device.

    Everything can be wired to be HOT 24/7 (HAAT) - or - ON with Ignition (HIR).

    Doc
    Last edited by Big Blocker; 09-03-2019 at 06:32 PM.
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    Senior Member CraigS's Avatar
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    Quote Originally Posted by Big Blocker View Post
    Terry,



    Grounds can be one size smaller than the power wire feeding the device.
    I never heard this before.
    FFR MkII, 408W, Tremec TKO 500, 2015 IRS, DA QA1s, Forte front bar, APE hardtop.

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    Senior Member Avalanche325's Avatar
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    Quote Originally Posted by Big Blocker View Post

    Grounds can be one size smaller than the power wire feeding the device.
    What? The same current flows through ground as power. Ground is the supplier of electrons. (Yes, there are both conventional and electron flow notations. Basically because Ben Franklin guessed wrong)

    If you are an electrical engineer or you played on in a movie......I gotsta know.

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    Senior Member FF33rod's Avatar
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    Quote Originally Posted by Big Blocker View Post

    Grounds can be one size smaller than the power wire feeding the device.
    And that's another vote against "one size smaller" on the ground. If anything, it should be the other way around, one size bigger. That way grounding is never an issue....
    Gen 1 '33 Hot Rod #1104
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    Senior Member MSumners's Avatar
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    As always learning a lot from the posts, thanks to everyone.
    I am at a similar stage of planning and want to have the trunk courtesy light wiring finished prior to installing the panels and spraying the lizard skin. Can I just tap off one of the rear harness wires for the courtesy light wiring? Has anyone used a specific switch?
    Likely simple questions but totally new territory for me.
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    Senior Member Avalanche325's Avatar
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    Quote Originally Posted by MSumners View Post
    As always learning a lot from the posts, thanks to everyone.
    I am at a similar stage of planning and want to have the trunk courtesy light wiring finished prior to installing the panels and spraying the lizard skin. Can I just tap off one of the rear harness wires for the courtesy light wiring? Has anyone used a specific switch?
    Likely simple questions but totally new territory for me.
    There are a couple different ways to do it:

    If you want the light to come on when you twist the headlight switch to the courtesy light position or another switch in the dashboard, you will need to run a separate wire for that. Just power, you would ground it locally.

    If you tapped off of the rear harness (running lights or license plate) you would have to have the running lights turned on for the trunk light to come on. You would also need a switch so it wasn't on any time the lights were on.

    If your battery is in the rear, you could tap off of that, with a fuse in the circuit of course. I would only do this with a switch that turns it off when the trunk is closed, not a manually operated one. It would get left on sooner or later.

    I don't have one, but prefer the first option. With the rest of the courtesy lights.

  18. #15
    Senior Member edwardb's Avatar
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    Quote Originally Posted by MSumners View Post
    As always learning a lot from the posts, thanks to everyone.
    I am at a similar stage of planning and want to have the trunk courtesy light wiring finished prior to installing the panels and spraying the lizard skin. Can I just tap off one of the rear harness wires for the courtesy light wiring? Has anyone used a specific switch?
    Likely simple questions but totally new territory for me.
    Lots of ways you can wire a trunk light. Just depends on what you want. Going to assume you would use either an LED light or an LED strip. In either case the current draw will be very low, so not super critical where you get the power from as long as it's properly fused. I've personally done it three different ways: (1) Extended a wire off the courtesy light circuit, so the trunk light went on along with the footwell lighting with a twist of the headlight switch. Battery circuit, so works with/without the car being on. (2) Extended a battery wire from the fuse panel (sorry don't remember which) and used a micro-switch on the trunk hinge to turn on/off. Because a battery circuit, works any time the trunk lid is opened. (3) Same as #2 except used a magnetic switch from O'Reily's. What's on #8674 and works great. Easy to install.

    Another option, which I haven't done but would be easy, would be to extend a wire off one of the rear light wires (license plate light or running light) and then switch on the hinge. Would work any time the lights are on and the trunk lid is opened, which in theory would be when it's dark and the trunk light is useful. Hopefully something there you could use. I'm sure others have additional choices.
    Last edited by edwardb; 09-05-2019 at 04:19 PM.
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  20. #16
    Member shackf16's Avatar
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    Terry,

    I mounted my Blue Seas 6-circuit panel right next to the stock mounting point for the RF circuit panel. Use a 60-amp master fuse with an 80-amp relay to power it from a battery feed, then triggered by the HIR setting from the ignition switch. That allowed me to keep the wiring accessible and routed together with the RF harness. I am using the RF electric choke circuit to power some LED running lights, and I have A/C (powered by RF heater wire) and will be using a stereo so both of the stereo wires (one HAAT, one HIR) will be used. I also have a wiper system so that RF circuit is also being used. I pretty much maxed out what I could "pirate" off of the RF harness, and had to add the extra 6-circuit for things like seat heaters, ABS, aux power, reverse light, and electric heater water valve.

    I am going to use the courtesy light feed wire (HAAT) to power my LED interior lights with a combination of a switch on the center console (rather than the headlight rotary) as well as switches on the doors. I can potentially see the need to turn on the interior lights at night while driving and don't want to have to change the gauge brightness to do so, or open a door! Additionally, I am going to have underhood LED lights as well as trunk lights running off of a fused HAAT circuit that will trigger whenever the trunk or hood is opened. I got a simple adjustable switch that goes to ground when it is extended which will close the circuit and turn on the lights. I will have it mounted so that the hinge presses the switch in when the hood/trunk/doors are closed, breaking the circuit and the lights go off. It's not too complicated of a circuit, since the dash switch and door switches all simply go to ground.

    Good luck!
    Shack

    Blue Seas fuse panel.jpg
    Mk 3.1, "Stock" 306 w/ Trickflow Top End, 4-into-4 headers, full MSD ignition, T-5, 3-Link, Ron Francis wiring all around, Autometer Ultralights, RT turn signal and gas pedal, NorthRaceCars A/C, heated seats, Hydroboost PS/PB (Brembo/Baer 13" combo), ABS, SAI mod, VPM sway bars, dual roll bars, dropped trunk, center console, APE hardtop, trick camera setup...too much time and $$$...one day she'll get painted! Delivered 8/05, first start 3/16/06, Go Kart 6/1/06, Titled & registered 7/21/08.

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  22. #17
    Senior Member Big Blocker's Avatar
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    Since we are talking about DC current - current that flows in one direction - and there is an electro-mechanical device being powered by this current, one could surmise that some of the current is dissipated at the device - hence a possibility to go one size smaller on the ground leg. In my original post (#9), I did say "can" be one size smaller, not that it [absolutely] must be or should be - this is a practice that is totally dependant on the circuit/device being powered.

    With that same thought in mind (current handling), if you tie a couple/few 16 or 18 Ga ground wires together to simplify your wiring, if you are taking each individual wire to a ground post, no worries. But, if you are looking to gang them together to a single wire to tie to that ground post, that single wire needs to be large enough to handle ALL the ground potential from the ganged wires.

    That ought to be clear as mud . . .

    Avalanche325, Slept at a Holiday Inn once . . .

    Doc
    Last edited by Big Blocker; 09-06-2019 at 10:52 PM.
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    Senior Member CraigS's Avatar
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    Yeah that is if current actually flows positive to load to ground. I have come across enough info over the years to suggest it may not be that simple. I don't really know for sure though so I always make + and - wires the same size.
    FFR MkII, 408W, Tremec TKO 500, 2015 IRS, DA QA1s, Forte front bar, APE hardtop.

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    Senior Member FF33rod's Avatar
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    Quote Originally Posted by Big Blocker View Post
    Since we are talking about DC current - current that flows in one direction - and there is an electro-mechanical device being powered by this current, one could surmise that some of the current is dissipated at the device - hence a possibility to go one size smaller on the ground leg. In my original post (#9), I did say "can" be one size smaller, not that it [absolutely] must be or should be - this is a practice that is totally dependant on the circuit/device being powered.

    With that same thought in mind (current handling), if you tie a couple/few 16 or 18 Ga ground wires together to simplify your wiring, if you are taking each individual wire to a ground post, no worries. But, if you are looking to gang them together to a single wire to tie to that ground post, that single wire needs to be large enough to handle ALL the ground potential from the ganged wires.

    That ought to be clear as mud . . .

    Avalanche325, Slept at a Holiday Inn once . . .

    Doc
    Unfortunately, that's not how it works. Current does not dissipate. What flows in has to flow out, it's like a water pipe (without a leak). What does dissipate is power - everything has a resistance to that current flowing and that resistance causes a voltage drop to occur across the item that has the resistance - wires, pumps, even connections. Power is voltage multiplied by current, so a voltage drop across a wire is now losing power in the system. So a battery may be putting in 10 Watts but the wires might be dissipating 1 W and the device being powered is taking 9 Watts. However, the same current is flowing through all the parts. What you want to do is minimize the resistance of your wiring so that you don't waste power - power dissipated in wiring is all heat.

    So why is ground so important? Well clearly the first thing is that we don't want hot wiring so we need decent sized power and ground wires. When a ground wire is undersized, the device it powers is no longer at the same voltage potential as it's surroundings. Quite often that causes the currents to flow through things that hadn't intended it to such as mounts. If the different is high enough it can be a safety hazard. But where it really causes "issues" (as in a real bear to debug problems) is when we're talking about electric or electronic devices sending signals to each other. If the devices are not at the same potential to begin with then they have issues reading what the signal is from each other.

    I'm sure that muddies things even further...
    Steve
    Last edited by FF33rod; 09-07-2019 at 10:43 AM.
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    Never heard of the smaller ground wire but it makes sense. Grounds to chassis are often shorter than feed to battery.

    1 foot of 18 gauge wire has less resistance than 2 feet of 16 gauge feed wire.

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    Member RBachman's Avatar
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    For residential use, code (here) allows a smaller ground for typical AC circuits. For DC, I always used the same size wire. The additional cost is negligible and it doesn't hurt.
    But for electrons moving in a wire, consider this analogy (a little flawed, but I don't want to dig out the calculations and remember calculus again. Still, it helps explains how it works).

    Think of wire as a very long water hose and electrons as water flowing through the hose. There are losses in the hose that rob you of pressure (friction losses, losses with turns, restrictions, fittings, valves, etc.. At the faucet the pressure may be 75psig, but pressure at the end may be half of that. Regardless, the same amount of water that enters the hose leaves the hose. In this scenario, the end of the hose doesn't need to handle the same pressure, and doesn't need to be as large. It's sort-of like that. However, it doesn't hurt to bump up a wire size and make them both the same, and the costs is minimal considering.
    FFR MKIV ordered 12 July 2019 for delivery Mid September, (Stewart had other ideas, so early October?). IRS, Wilwood Brakes, 18" Wheels w/MT tires, power steering, EFI, AC/Heat. 347 Dart by Mike Forte. All new, no donor build. Jeff Kleiner will provide body and paint work.

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    Terry. Like Big Blocker, I like the Blue Sea Systems fuse block. They are used in marine applications and I recently used two to build a lithium battery based solar generator. I am pretty good with all types of electrical and you should have the same sized positive and negative wires and you size the wire powering the fuse block based on the load. Blue Sea has pretty good info on their website for calculating wire size and lengths. They even have a app, however i have not used it, buy you may want to give it a look. Hope this helps. Cheers. Tom.

    https://www.bluesea.com/support/arti...r_a_DC_Circuit

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    I prefer to avoid fuses when I can. I use automatic resetting circuit breakers for most circuits I build. You can see them in the bottom of the picture, with red rubber covers.

    I also like Bus Bars for power distribution. Simple, reliable, inexpensive. You can kinda see it under the relays, to the right of the circuit breakers.

    For anything that's computer controlled, or sensor controlled, I think a quality relay is very important.
    Last edited by Bob Cowan; 10-07-2019 at 09:25 PM.
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    Thanks Gizmo. I ended up using a 6 panel fuse box with a negative bus. I used a 50 AMP rated relay that was triggered by the RF stereo wire so that it is only hot when the ignition is on. I have a 12 AWG positive wire (about 5 ft long) with an inline 40 amp fuse powering the fuse box. I have a 12 AWG wire for the ground connected to the frame that is less than 1 ft long. I currently have 4 items hooked up to it. The two seat heaters with an 10 amp fuse each. One for the USB and one for the cigarette lighter/accessory plug with a 10 amp fuse each as well. From what I understand, these two will draw quite a bit less than 10 amps. I ran the positive and negative wires for each accessory in a sheath and used the negative bus for grounding. I learned a lot from doing this. I got a lot of help from this forum and from Big Blocker.

    According tho that chart, I might be undersized for my fuse box power wire. The RF harness also looks like it uses a 12 AWG wire (that's what I based mine off of) but it is pulling quite a few more amps than my accessory fuse box. Should I get larger wire for this? 8 AWG seems like massive overkill to run two seat heaters and USB chargers.

    Terry
    Last edited by TMartinLVNV; 10-07-2019 at 09:29 PM.
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  32. #25
    Member RBachman's Avatar
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    Quote Originally Posted by TMartinLVNV View Post
    Thanks Gizmo. I ended up using a 6 panel fuse box with a negative bus. I used a 50 AMP rated relay that was triggered by the RF stereo wire so that it is only hot when the ignition is on. I have a 12 AWG positive wire (about 5 ft long) with an inline 40 amp fuse powering the fuse box. I have a 12 AWG wire for the ground connected to the frame that is less than 1 ft long. I currently have 4 items hooked up to it. The two seat heaters with an 10 amp fuse each. One for the USB and one for the cigarette lighter/accessory plug with a 10 amp fuse each as well. From what I understand, these two will draw quite a bit less than 10 amps. I ran the positive and negative wires for each accessory in a sheath and used the negative bus for grounding. I learned a lot from doing this. I got a lot of help from this forum and from Big Blocker.

    According tho that chart, I might be undersized for my fuse box power wire. The RF harness also looks like it uses a 12 AWG wire (that's what I based mine off of) but it is pulling quite a few more amps than my accessory fuse box. Should I get larger wire for this? 8 AWG seems like massive overkill to run two seat heaters and USB chargers.

    Terry
    For 40 amps at 5 feet the 12 is probably okay, but may be a little small if under full load. Here's a chart that may help you out a bit. Scroll down to the bottom of the table. There's a simple calculation that will help out. Basically, you calculate the Voltage Drop Index, (VDI). VDI = (amps x length-ft.)/(volts x allowed voltage drop). 3% is good for a voltage drop. Compare what you have with the VDI numbers in the table.

    https://www.altestore.com/howto/wire...-systems-a106/
    FFR MKIV ordered 12 July 2019 for delivery Mid September, (Stewart had other ideas, so early October?). IRS, Wilwood Brakes, 18" Wheels w/MT tires, power steering, EFI, AC/Heat. 347 Dart by Mike Forte. All new, no donor build. Jeff Kleiner will provide body and paint work.

  33. #26
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    Quote Originally Posted by TMartinLVNV View Post
    Thanks Gizmo. I ended up using a 6 panel fuse box with a negative bus. I used a 50 AMP rated relay that was triggered by the RF stereo wire so that it is only hot when the ignition is on. I have a 12 AWG positive wire (about 5 ft long) with an inline 40 amp fuse powering the fuse box. I have a 12 AWG wire for the ground connected to the frame that is less than 1 ft long. I currently have 4 items hooked up to it. The two seat heaters with an 10 amp fuse each. One for the USB and one for the cigarette lighter/accessory plug with a 10 amp fuse each as well. From what I understand, these two will draw quite a bit less than 10 amps. I ran the positive and negative wires for each accessory in a sheath and used the negative bus for grounding. I learned a lot from doing this. I got a lot of help from this forum and from Big Blocker.

    According tho that chart, I might be undersized for my fuse box power wire. The RF harness also looks like it uses a 12 AWG wire (that's what I based mine off of) but it is pulling quite a few more amps than my accessory fuse box. Should I get larger wire for this? 8 AWG seems like massive overkill to run two seat heaters and USB chargers.

    Terry
    Hi Terry. According to spec it’s undersized a little.

    I think your likely ok. The driver on it is the seat heaters pulling the amps. If you think you could actually pull 40 amps then go ahead and upsize. But i agree your probably a lot less. Maybe 20 or so. You could do a little test and put in a 20 or 25 amp fuse in the in-line. Then run your seats and plug a few USB gadgets in. No breaky break and your good. I’d probably leave a 30amp in the in-line as that is closer to the wire size u have.

    The relay to power it is a nice idea as it will turn off the entire fuse block when u turn the car off. I’ll remember that.

  34. #27
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    That's a great suggestion. When everything is hooked up, I can turn both seat heaters on high and plug in chargers to my USB and a GPS in my cig lighter after changing out my in line fuse for the fuse box power to 25 amps and see if it blows. If it does, I'll change out both the ground and the power wire to 10 AWG.

    Thanks guys.
    MK IV Build #9759, 3 link, 17's, Forte 347, Sniper EFI, power steering, built for a freak sized person with 17" Kirkey Vintage seats, RT drop trunk, RT turn signal, lots of stuff from Breeze Automotive, Wilwood brakes

  35. #28
    Senior Member Avalanche325's Avatar
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    Quote Originally Posted by CraigS View Post
    Yeah that is if current actually flows positive to load to ground. I have come across enough info over the years to suggest it may not be that simple. I don't really know for sure though so I always make + and - wires the same size.
    DC current actually flows from negative to positive. Not that it matters for wire size. + and - need to be sized for the full load, as you said.

    As FF33rod stated, if you are electrically challenged, think about wires like pipes and switches like valves. People seem to be able to get their head around that easier. The one rule is that you always have to have a return pipe back to the source.

    I am not a fan of auto resetting circuit breakers in a car. They are for things like aircraft critical circuits where burning your wires or damaging a component is better than crashing. If a breaker trips, there is a problem that needs to be fixed before applying power again. Fuses actually provide better protection for sensitive electronic components. Fuses open the circuit faster than a circuit breaker on a major fault. Go figure, the most convenient option offers the least protection. The law of the universe.

  36. #29
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    I learned a lot doing this part of the build. I dreaded it beforehand, hated it during, and now can look back and say that I actually had fun doing it. On my Jeep I have all kinds of accessories all hardwired using in-line fuses of different types. I'm actually considering getting two aux fuse boxes (one for the rear area powering amps and an air compressor and one up front for KC lights, air compressor for lockers, aux trans fan) for it just to clean things up. After the Roadster is done of course.

    Thanks for all of the help everyone provided. I hope this info comes in handy for someone else.

    Terry
    MK IV Build #9759, 3 link, 17's, Forte 347, Sniper EFI, power steering, built for a freak sized person with 17" Kirkey Vintage seats, RT drop trunk, RT turn signal, lots of stuff from Breeze Automotive, Wilwood brakes

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