Thanks. Ill probabaly start this weekend. Im guessing that the hardest part will be getting the wires from the lights into the engine compartment. In the past, Iv read a few posts about how to do it but Ill for sure need to go back over them. Good luck with the horn, how big is it?
thanks again
jason

 

I have basically the exact same setup as you, except without the power requirements (mine are 55/55/55, plus I run camera power & 12V outlet on the rack), so I'm pretty familiar with the 'ideal' and the 'acceptable' way for setting this up, with relays...plus there's some questionable advice here as well and I think you'd like to have nice bright lights and not burn up your truck, so I figured I'd chime in

#1 - You can't use house wiring/AC as a guide for current capacity for DC circuits. House wiring is solid vs stranded (makes a HUGE difference in capacity, a closer example would be an extension cord, which has a much lower capacity per wire size, plus...). There's also a fundamental difference in the way AC works vs DC. Think of it this way - AC is a wave, so a portion of the power is at zero (when the wave passes zero), DC is always 'on' - meaning you are actually carrying the current full time, so you ultimately flow more electrons (current) with DC than you do with AC. It may seem like 'no big deal' but it makes a big difference when you are at/near the current capacity of the wire - less of a difference if you give yourself a big 'fudge factor' in your wiring diagram. By fudge factor, I mean using 2 sizes larger wire and you'd be ok (for reference, I went and looked it up in the NEC - while the uses vary, 60A generally requires 8GA, in a house, controlled environment, no vibrations, etc, I know there's a table specific to this application, but I didn't feel like digging through the whole book lol). On my setup, I have 6GA wire as my 'feeder'. Another note, if you use smaller wire you'll get restrictions in the current flow and your lights won't be as bright (think of it like a garden hose, you can get more water out of a bigger hose). While the current capacity is a safety issue, the brightness of the lights is a HUGE difference between wire sizes, especially on rear lights that have a longer wire run.

#2 - You should never 'put in a fuse and if it blows replace it with something larger' - fuses are there to protect your wiring from getting hot, melting down, shorting against your chassis and causing a fire (or if you are running 60A total and it shorts, you can actually cause problems with the sensitive electronics on your rig...like your PCM/BCM). Assuming you go with 8GA, a 60A circuit breaker, or megafuse would work (you can get cheap megafuse + holders at VTEWorld (like under $10 for both fuse/holder, go with the ANL type, it's the same quality, but cheaper). If you go with 6GA, an 80A fuse would work (more power!).

#3 - As for your wiring, the easiest (and cheapest) way to wire it is one big wire up to the rack (I'd vote for 6GA, but 8GA would get you by)...on the rack end, have that wire end in a 1/4" ring connector (you can get these real cheap at Homeless Depot for 6GA wire and can crimp it down to 8GA if needed), on the battery end, have that wire connect to your megafuse block with fuse (you should always have the fuse as close to the battery as practical).

For your FRONT lights you need a larger wire (10GA is best), for your REAR you can go one size smaller (12GA would work). All of those should be fused separately (otherwise they may get a small short, get hot, melt the insulation and cause a fire). You can get cheapo automotive relays at Rat Shack (or just about anywhere really, Wally World might be cheaper). Bunger already outlined the wiring + there's info on the package. You connect the main wire (the 6GA wire) to a 1" long by 1/4"-20 machine screw, and attach the three (10/10/12) other wires (one for each relay) to that as well (best to use ring connectors), use a nylock nut to make sure it doesn't rattle loose (nylocks are the nuts that have the little piece of plastic inside the threads to hold it in place). Wrap the whole thing in layers of electrical tape. Connect those wires to one of those inline fuse holders and then connect it to the relay. You don't need a fuse between your relay and your lights.

For your control circuit (from your switches to your relays), you can actually use CAT5 cable since the relays don't draw much current (under 50 mA). That allows you to run a single CAT5 cable from in the cab up to the roof rack.

So, if you use a main 'feeder' line from your battery to the rack and a single CAT5 for control, you only end up having to run 2 wires to your rack. They will fit under the A pillar molding rather easily

I attached a diagram, hope it helps

Here's a full parts list:

6GA wire - about 8' should get you to your roof rack depending on where you connect all your wires.

80A fuse & block (VTEWorld -->ANL Fuses & ANL Fuse Holder)

1"x1/4"-20 machine screw (honestly, a terminal block makes this much easier since it eliminates all the extra inline fuses...something like this -->Amazon.com: Sierra International FS40420 ATO 6 Gang Marine Fuse Block: Automotive)

A bunch of 10GA and 12GA wire

3x inline fuse holders (Amazon.com: In-line ACT Water-resistant Fuse Holder - 10 AWG: Automotive)

3 relays (Amazon.com: Absolute RLS125 12-VCD Automotive Relay SPDT 30/40A: Car Electronics)

8' of CAT 5 cable (when you are wiring this, you can use 2 conductors per circuit since it has 8 conductors)

A few last comments:

Using a fuseblock makes it a lot easier to wire on the roof rack. You can get a waterproof fuse block pretty cheap (<$20) and that saves you having to wire the inline fuses - just attach each light wire to the fuseblock.

Getting a waterproof box for all the stuff on the rack is a good idea...a simple cheapo waterproof electrical box from HD works well.

I'd suggest shrinkwrapping all your connects, but honestly wrapping some electrical tape around them works pretty much just as well.

If you go the screw route to connect your wires, use stainless, it conducts well and won't tarnish/rust as fast as zinc/galvanized.

If you can (speaking from experience) put your wires in a wire loom and zip tie them all over the place! I've actually had even a short run of wire short out (lucky I was fused and no fire no foul)...especially on the rack, you aren't likely to notice a short and without good fusing, it can cause a fire - and not always at the short...it can happen at the main connection to your battery or anywhere else.

Go with the biggest wire you have/can afford, it will make a huge difference, especially with lighting...lights are uber-sensitive to voltage differences and smaller wire=lower voltage.

HTH

 

Thanks for the post! So are you saying to run 6ga from the engine compartment up to the rack and then having a fuse block and 3 relays mounted on the rack? I got a little lost, LOL. Let me go back and read it a few more times.
thanks for the links BTW!
jason

 

ac . the voltage cycles + and - so it can be "transformed" up/down. a spec of 6 v ac means the ac has the same effect as 6 v dc. the actual voltage swing is 2.828 times 6v but it doesnt matter since the 6 v ac (rms) is the same as 6vdc.

wire is "guaged"so you know how much current it can handle. in the same situation,solid or stranded is pretty much the same. we always us bigger than needed for safety so it can be considered the same but stranded holds up better.

if you start with a small fuse without the bulbs you are checking just your wire for shorts.
a 1 amp would be ok. then when the relays work,go to full size.

lights are not critical of voltage,they just get dimmer with lower volts and last longer.

im not telling u how to do anything , just filtering bs!! personally id use all #12 to keep it simple,and manageable. i cant imagine running 6 up to the rack!! your choice.

oh,my oogah horn from the 1920's. ill get a pix

 

Exactly that

 

I think we disagree on some of the details here

DC current runs 'hot' all the time - there is no zero cycle, which means it's always '+' vs AC which has a + zero - cycle - this is why DC circuits have a + & - and AC circuits have a 'power' and 'neutral' - if you add up the time spent 'energized' (ie with current flowing) for an AC circuit, it will have lower overall current flowing through it...hence the ability to use smaller wire for AC.

Solid v Stranded...if you look at NEC current capacities, all solid wires have greater capacity than stranded...the cross-section of a solid 12GA wire is greater than the cross-section of a 12GA stranded...hence it can carry more current (or the same current at less voltage loss)

Some good information here (see the table of AWG gauge sizes) -->American wire gauge - Wikipedia, the free encyclopedia

In looking at that and the current carrying capacities, it might even be a bad idea to go with 8GA to the roof if you ever plan on running all lights at once (and would be a smart idea)

Looking also, it looks like AC @ 60Hz doesn't have enough of an impact on current to affect the ratings, so I stand corrected (I'll retain some dignity by saying technically the current draws are different, just not enough to make a difference at 60 cycles )

To see the impact of wire gauge on light brightness, hook up a light to a 14 GA then 12GA then 10GA and even 8GA if you have it...the voltage drop is greater over distance (it's a function of distance, current, wire type, size, etc. For example, on a 20' run, 14GA will have ~8.8% voltage drop while 10GA will have 3.5%...may not seem like much but my experience is that's noticeable on lights

Good idea on using small fuses to check for shorts to start. I think I misinterpreted your comments, sorry about that My only advice to the OP would be to use an appropriately sized fuse for the wire size (not based on how much is needed to run a light)

 

finaly got most everything hooked up. I dont have the rear lights wired in yet, but maby this weekend... heres my toggles.

and heres the lights.. the 2 outside lights are operated by the left toggle, the 2 inside lights are opperated by the center toggle,, and the rear lights will be opperated by the right toggle.

 

looks like a row of headlites up there. looks good, should be able to signal planes for landing....

good thread.

 

Need help putting 50k HID yea
They are super blue but had seen picture on how
To relay but cant seem to find the site again where i saw how to diagram

 

Chris


All the relays use the same pin out,


#85- Coil -
#86- Coil 24vdc +
#87- Lamps
#30- 24vdc +


Power the #86 of the relay from a source that provides 24vdc + when the ignition is on. Then power the #30 of the relay from the appropriate sized fuse for your lamps. When the relay closes power goes through it and out #87 to your lamps.


(If you want the lamps on any time combine #86 and #30 together then go to the correct size fuse for your lamps).