Wiring diagram complete re-design: diagram included

[geezer]

It is very convenient to locate a Power Distribution Center, housing the nessesary fuses and relays in the engine compartment, minimizing the lengths of wire needed to power the forward lighting, horns, fan(s), etc. I'm curious to see where you will locate it, keeping it out of sight but easily accessible. Just as the original wiring was divied into an engine harness, instrument panel harness and body harness, you will find your new electrical system will more or less follow the same exact pattern with the exception of adding relays into the circuits.

There is one thing I would like to point out. It doesn't make any difference how you wire the relays with the circuits you have created in your diagram but it is not the way I normally do it. You are supplying voltage to pin 87 of the relay, which when triggered allows voltage to exit via pin 30. I have always reversed this; in pin 30 - out pin 87. The circuit will work the same, but you can also take advantage of pin 87A having voltage while at rest only, in case you wanted to utilize that feature. The other way you can't. Minor detail, otherwise, great diagram as far as I can see!

Edited March 28, 2010 by geezer
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[crazyoctopus]

distribution center was taken out of a nissan maxima (if you find a 93 they are slightly easier to work with) total cost $6 at a junkyard. the other way would be to actually buy a pre-built fuse box for $16-$170. with the relays, take it off the smae car and they are pre-wired and fairly easy to identify the amperage, just takes some internet browsing. awesome thing about the nissan relay housings is that you can connect however many you want to eaachother (run anywhere from 5-500 relays and they all snap into eachother)

as far as the mounting goes, the 240sx (s13) center console lends itself perfectly for the mounting of the fuse box. The relays will be mounted under the dash near the switches.

as far as the wiring goes; all of the relays that I buy/use, except the wiper, are 4 terminal relays. In the case of the wiper motor I am even thinking about just cutting that down a bit and making it switched for fast-off, instead of slow-off-fast, but i am still thinking about it.

We have made a few more adjustments since rev6, some of the amperages were a bit excessive, decided on going with an eBayish 12v heater, and I moved/removed a couple more circuits/switches/relays that really didn't need to be there.

full size >> http://farm5.static.flickr.com/4053/4469515326_a17763031f_o.jpg

[WingZr0]

Don't know if you thought about it or not but do you need the light inside of ashtry? Don't know if all Z's have it but my 77 does, never worked though.

[crazyoctopus]

nope not going to use it. the interior lighting is going to be taken care of from a flashlight.

if you really wanted to add it, i would tap it off of the heater circuit with a switch.

[crazyoctopus]

the alternator wiring was brought up on hybridz, and I had to make sure that it was also clear on classicz as well.

==

after doing a bit of looking, i knew there was a reason why this set up was working, and found the link i was looking for http://www.camaros.net/forums/showthread.php?t=115803

if you look at my diagram the splice connecting the alt to the coil is after the delco 8078 pigtail.

The splices in the diagram in its current state do not relate to the actual placement on the car just to be used as a reference, for now.

[geezer]

I can understand the concern getting the alternator wiring correct. I haven't had the experience of converting to an internally regulated alternator of the Nissan variety, but have done so with GM SI-10 & SI-12 alternators for years. We liked them because of the ease of wiring, cheap cost and in our boats it didn't matter what direction the SIs alternators rotated. I imagine the same principals apply. I have always used a diode in line on the excite wire instead of a resistor, tapped into the fused ignition run circuit. It must be a dead circuit, when in your case the ignition switch is off. The sense wire should come from the far reaches of a likewise fused circuit. You cannot connect directly to a Batt feed. The alternator would not be able to accurately compensate for accessory loads if connected directly to the battery. One other thing I notice is the absense of a ground wire coming off the alternator lug, which should run to the neg. battery post. Don't just rely on the ground provided by mounting if you want to avoid trouble.

I did notice the one comment on HybridZ relating to the importance of your diagram. I think it is very important, especially as time goes by. It has been about ten years since I designed and built my last complete custom harness and without all the crude drawings and hand written explanations I made at the time, I would be in for a whole new learning experience, when it came time for troubleshooting. Here's a few examples of the crude drawings and explanations I found nessesary at the time. You may be able to use the fuel pump circuit.

Edited March 29, 2010 by geezer
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[crazyoctopus]

thanks for the input, and the wiring was a good reference; however I don't think i will be using it with this diagram. while it does kill the pump in an accident, it also adds complexity. For a non-track car, or for a restoration car i would definitely add this bit of safety into it, but to keep cost down and simplicity high, no real need.

as far as the diode goes, what type are you using? I have also heard of using a charge light, but i am truly lost when people start talking about it. if i use a regular 2-pin led/autometer light would that work?

[geezer]

These illustrations should clear things up for you. Although GM SI alternators are used as examples, a ZX internal regulating 3-wire alternator should follow the same principals. I took a pic showing the diode connected to my multimeter. You can see the band on the end of the diode signifying the direction current can travel. Consider the band the point of an arrow. The diode will prevent the engine from "running on" after the ignition switch has been turned off. They are $1.59 for a package of 3. In the first illustration, the basic "it will work" method is shown. Ok for a car with very limited battery draw from accessories and maybe what you want but most of us would benefit from the second example.

Edit: Sure, the Autometer light will work as long as it is wired in between the ignition switch and the alternator. Myself, I like the convenience of a light, as it keeps you more aware of how/or if your charging system is functioning.

Just a note concerning the second illustration: The #2 sense wire will better regulate a heavily taxed electrical system if connected to a distant fused source.

Edited March 30, 2010 by geezer
added stuff

[crazyoctopus]

If the battery were mounted under the hood the ground wire attached to the alt would be prime; but mine is going to be mounted in the rear passenger bin so that wire would have to be at least an 8 gauge. I am going to probably going to use a 8 to connect it somewhere on the firewall.

I did make one change to the second diagram that you sent, and that is instead of running 2-wires back to the starter I am going to use a jumper from the # to the Batt on the alternator and run one wire back to the starter.

updated diagram. spliced points moved on the starter to better show where the wires will be meeting. also added the information for properly wiring the alternator via geezer

larger image http://farm3.static.flickr.com/2732/4477751862_9ff537d584_o.jpg

[geezer]

Little bit of a boo boo there showing a neg. at the starter? For clarity you should show the starter solenoid with the correct connections. Improvements can be made here. The alternator charge wire should connect directly to the starter solenoid and then continue on to the Fusebox/Power Distribution Center. For later consideration, the diode should be as close to the alternator as possible for easy accessibility.

The “Alt Coil Relay” can be eliminated. The alternator doesn’t require a relay and the 12V to the Coil can be supplied by an Ignition Switch that would replace what you are calling the Safety Switch, which does nothing where it is presently located. The Kill Switch is the only way to shut off the engine in your diagram, other than the "Alt Coil Switch", which should be gone, or the Fuel Pump Switch.

I would put the Kill Switch where it would do just that. Kill everything. Having the Battery located in the storage compartment, it would be easy to locate the Kill Switch within easy reach. Then again, you probably have it figured out where you are going to hide it already. No sense advertising that.

It also seems to be inconvenient, having to flip a switch for a Reverse Flood Light. A little creativity here would make it an automatic feature, taking the possibility of human error out of the equation, converting the switch to an override function instead.

I would also incorporate Fusible Links or better yet Maxi Fuses into the circuit. I see the potential for lots of improvements, which will also keep it simple. If you want, I can make a few quick drawings to explain better.

Edited March 31, 2010 by geezer

[crazyoctopus]

Thanks for the incredible corrections to the diagram!

-starter: yeah a bit if a boo boo there. There are really only two places that the wires can go so I just made one a neg. When I have a chance I'll make it clearer as to where the wires go; most likely either use the one from the second diagram or make my own from a fronal view of the starter. Diode will be moved at te same time

-Safety switch: was put in place so that the starter button would not activate if the switch was off.

-alt coil relay: great news about the loss of a relay. I am a bit confused about your suggestion for the coil wiring. From what I understand all that I would need to do would be to replace the relay with a switch and keep the wiring how it is.

-kill switch: as per, I think, SCCA regs you need to have a way to turn off power to everything from the driving position. I want to make it so there are two. One that is easily accessable and the other that will act as the safety somewhere else in the line; the initial "safety switch" was something along those lines, but just not as potent.

-reverse flood switch: in reality the only reason why this is there is because my reverse switch that is attached to the tranny has both of the wire snipped/snapped/broken off, so this was the only way for me to get reverse lights until I find another switch. When that happens I plan to route the stocks lights to it, and the flood attached to a switch.

Please please, do make drawings to correct/modify/change the diagram to simplify/clarify the diagram.

A question on the uses of fuseable links/ maxi fuses: why would you need one if there is already one in that circuit?

Thanks again geezer!

[geezer]

Not so much a correction, but maybe tweaking, nitpicking...whatever. You have a good basic plan here and your explanations have helped me understand it better.

The Safety Switch is a problem for me. You would have to get into the habit of flipping that switch off everytime you have started the car. It's your choice but I would prefer having a Starter Button equipt with a spring loaded, hinged protection cover, which is fool proof, instead of a switch that you may forget to flip off.

The Alt Coil Relay; I think I just have a problem with the name and the lack of separation from any alternator wiring. Replacing it with a dedicated Ignition Relay would simplify future trouble shooting of both the ignition circuit and charging circuit. Just something to think about. I will draw up an idea for you to look over.

Do you have the SCCA rules covering the venues you are interested in? Lots of help can be found from the guys on this site. It would be a good thing, to be well versed on the rules before you waste any time and money on things that may have to be changed in order to comply.

Now that I know the reasoning behind the Reverse Flood Light, I would think the best option would be fixing the stock switch & wiring for the backup lights.

Fusible Links are typically found in close proximity of high amp sources and intended to protect the downstream wiring. It's much easier to replace a fusible link than a football field length of wiring that is wrapped and tucked out of sight before reaching the fusebox. They are never used inside a vehicle and if you have ever seen a fusible link blow out in the dark you would know why. The fuses used for protecting individual circuits have a tendency to wear down over time from the effects of accessory start up where you can have a brief amperage spike of twice the fuse rating and also from the corrosion and consequenses of over time. I have seen some fusible links that are still doing their job 30 plus years later. The people that have modernized their cars with Maxi fuses seem to be happy with the results and I haven't heard of any problems from anyone doing so. They are just better in the sense of being more convenient, durable and I would say safer with less chance of fire occurring from a flash burnout.