FRESH START: Alternator Wiring Upgrade Configuration

[svxcess]

The original thread got very misleading and confusing and it was probably because I was not very clear. I would like to start over again and be more understandable on what was done and my options. Please bear with me on this.

Trevor,

Thank you so much for all of the time you have invested in this on my behalf. It is most appreciated. As you said, the wiring diagram is most confusing when compared with what is actually in place. What I see in person is not actually what is in the schematics. Let's start over.


HISTORY

Like most members, I had original factory circuitry that was never modified in any way. At one point, the only change that was made was the addition of a 4 gauge wire between the battery and the alternator, the now-famous “alternator wiring upgrade”. That was done on my 1996 Polo back in 2002. I had previously done the same mod on my 1992 pearlie.

Earlier this year I noticed that the ends of the two white wires that ran through the black plastic conduit among the top of the engine, TO the alternator, had cracks in the insulation and had become brittle. They were the two white wires that attached directly to the alternator charging post.

At the same time, I also noticed that the two wires attached the alternator plug on the side of the alternator were dried out and brittle as well. These two wires ran FROM the alternator back through the same black plastic conduit. Both of these had deteriorated, probably due to age and heat from the engine compartment.

I bought a new alternator plug with the two wires already attached. Before replacing the alternator plug with the new one, I decided to open the black plastic conduit to see what the wires looked like inside. The two small wires that were attached to the original alternator plug looked fine. I thought I would just install a new alternator plug, soldering the wires on the new plug to the same wires that were connected to the old one. No problem.

The two white wires that were connected to the alternator charging post with ring terminals were dried out and cracked their entire length. I thought I would follow them back until I found good wire, trim them and solder replacement wires to them and run them back to their original connection at the alternator charging post. So all I would have done is remove bad wire, replace it with good wire and keep the original connections, with all the wires running through the plastic conduit, as originally designed

But the black plastic channel was breaking apart and very brittle. At first I thought about running all of those wires through split loom for protection, as had done before on my 92 pearlie, but the loom would last only about 2 months before it needed replacimng because of engine vheat deforming it. See photo below of the 92, with the looms now replacing the plastic conduit.

I attempted using the split loom again on my 96 a few years ago (before I found a used black plastic conduit) This was more heat-resistant, but still lasted only about 4-6 months before it needed replacing.

Here is a photo of the split loom, with original black plastic conduit in place, taken about a year ago. The conduit has deteriorated since then.

I decided not to use either the split-wire loom or the black conduit, so I routed the wires a little differently. The two wires FROM the new alternator plug (in the side of the alternator) were only lengthened about 10" so that they would run behind the alternator and under the engine manifold, instead of along the top of the engine as originally done. They still are connected in the same way as the original wires were, just a little longer.


It was the two white wires from the charging post that is causing all of the concern here. I mistakenly thought that long as I was trimming the bad wires back so far to solder in good wire, I could just attach them directly to the battery instead of running them back to the alternator. Because the heavy 4 gauge power wire of the alternator wiring upgrade gave me the same 13V at the battery as the alternator, I assumed it would not make a difference-- different connection point, same voltage. I did not think I was bypassing a fusible link in the original circuit.


The rest is history. So here is what we currently have:

ALTERNATOR PLUG: No difference or changes at all. New plug replacing old plug, with their wires lengthened to allow them to run under the manifold instead of on top.

THE TWO WHITE WIRES: They were cut back to where there was good wire, new ring terminals attached and connected directly to the battery instead of the alternator charging post. This seems to also bypass the safety fusible link circuit. These are the only wires that need attention


OPTIONS:
A. Remove the two white wires now attached to the battery, lengthen them enough to reach their original connection point at the alternator post. That’s it. Original circuitry as designed is maintained. Fusible link in circuit is active. The only difference is that the wires are new and not degraded.

B. Remove the two white wires now attached to the battery, and splice then together to form one larger gauge wire. Attach a fusible link between the end of that wire and the battery. Fusible link protection is maintained. [/B] OR

C. Remove the two white wires from the battery. Do not splice them together, but attach a fusible link to each wire and connect both of them back to the battery. Fusible link protection is still maintained.

More information on this can be found on THIS WEBSITE

I think B or C above would be the most desirable options for keeping an uncluttered look while providing overload protection for the 10 gauge wire circuits.



Option A requires nothing to be determined. We are just returning to the stock configuration, only replacing damaged wires with new ones

Options B and C require either the amperage rating or the size of the fusible link to be determined. Available fusible links range from 30A to 100A.

Fusible link wire is determined by the size of the original wires it is protecting, always being 4 numbers smaller than the wire it is connected to. The 2 white wires we are protecting are 10 gauge, so the proper fusible link wire use would be smaller 14 gauge, or FL-14. This is a gray color, same as the fusible link in our underhood fuse box.

Fusible link ratings (wire size) are coded by color.

Any final suggestions? This will be my final posting on this topic and I thank everyone here for their concerns and valuable input.

.

[Trevor]

Good idea to start afresh. You confirm your intelligence as I would expect. You also confirm that you have a very real reason to become confused.

My JDM car does not have the two white wires which you describe, connected to the alternator charging post by means of ring terminals. You advise that they ran along the top of engine but not where they were finally terminated, i.e. were connected to at their opposite ends.

It is these wires which have caused the confusion, particularly as they are white. They would provide battery volts so that I wonder if a previous owner fitted them, to supply an accessory of some sort.

So as not to restore confusion, please at present keep these two white rogue wires as the sole topic .

Poosibly there is another SVX available, that you could compare with yours, as a means of ensuring the rogue wires are original and connected accordingly?

This has been a long haul but we will stick with it, there being no drastic problem other than confused wiring.

Sincerely, Trevor.

[SVXRide]

John,
I agree with Trevor on the desire to have more description of the "white wires". Can you take a few more pics and post them up?
-Bill

[svxcess]

Good idea to start afresh. You confirm your intelligence as I would expect. You also confirm that you have a very real reason to become confused.

My JDM car does not have the two white wires which you describe, connected to the alternator charging post by means of ring terminals. You advise that they ran along the top of engine but not where they were finally terminated, i.e. were connected at their opposite ends.

The 2 white wires ran back towards the battery and into undisturbed factory insulated sheathing. I did not follow them all the way back to the opposite ends, just removed the sheathing far back enough to remove the bad portions of wire.

It is these wires which have caused the confusion, particularly as they are white. They would provide battery volts so that I wonder if a previous owner fitted them, to supply an accessory of some sort.

NO. There are the original white wires that came on the vehicle, as well as on my previous SVX. They are the same 2 white factory wires that ran through the black conduit and into the insulated wiring harness, which was never disturbed.

If other members here can support my observation, please do. Has anyyone else found there to be 2 white wires attached at the alternator post? Having removed alternators from other SVX's, I have had to remove these 2 wires many times.

Is it possible that the JDM cars (Japan, Australia, NZ) have only one wire instead of two? Can owners of these cars verify that?

So as not to restore confusion, please at present keep these two white rogue wires as the sole topic.

Agreed

Possibly there is another SVX available, that you could compare with yours, as a means of ensuring the rogue wires are original and connected accordingly?

As I stated earlier, On my 92 SVX, the same 2 white wires were present. I ran those white wires through split-wire loom because of cracked, brittle conduit. (this is the first photo in the previous thread) I encountered the same 2 white wires on my 1996 SVX. A I said they ran into the factory harness/sheathing, which had never been disturbed

This has been a long haul but we will stick with it, there being no drastic problem other than confused wiring.

Have you given any further thought to the 4 options I outlined as a safe and acceptable remedy to the present attachment point at the battery?



.

[svxcess]

.

UPDATE

In the Power Supply Routing schematic in the FSM, one of the white wires seems to go through the fusible link, the second one does not. Out of the two wires, one is protected and the other does not need to be.

But both wires look identical in color and gauge, so I cannot tell which one needs the fusible link in the circuit. So to be on the safe side... I chose Option C

I am disconnecting the 2 white wires from their connection at the battery and cutting off the ring terminals. I am attaching a 14 gauge fusible link wire (with ring terminals attached) to each of the wires, using a crimped and soldered butt connection with shrink-wrap.

I am re-attaching the 2 wires, now with fusible link protection on each one, back to the battery. This seems to be even safer than the original stock circuit.

The original circuit had only 1 white wire with fusible link protection, and 1 white wire without.

The new connections have both wires protected. 1 white wire with 2 fusible links and the other wire with one.

The 14 gauge fusible links are designed to protect the 10 gauge wires that they are attached to. I have confirmed this from many sources.


.

[svxash]

Here's some pics



wires come out (near the corner of battery) then go into cluster of wires.

[svxcess]

View of wiring with plastic Channel removed. These four wires all originally ran inside the channel .

.

[benebob]

Originally Posted by svxcess

The 14 gauge fusible links are designed to protect the 10 gauge wires that they are attached to. I have confirmed this from many sources.


.

But again John, DOES the amount of amps that can run through the 10 gauge wires with the new higher frying alternator meet standard electrical practices? That is the more important question.

[svxcess]

Originally Posted by benebob

But again John, DOES the amount of amps that can run through the 10 gauge wires with the new higher frying alternator meet standard electrical practices? That is the more important question.

It should not matter. The higher output from the alternator is on demand only. It will not put out more current than what is demanded by the original circuits. Whatever current was supplied to these circuits by the stock alternator will still be supplied by the higher output one.

If the regulator fails, the fusible links will blow before damage can be done. Fusible links are rated by color (the same way that fuses are) the 14 gauge link will hwve a gray color to indicate its size-- this is the same color gray covering on the fusible link inside the fuse box in the engine compartment.

.

[Trevor]

Originally Posted by benebob

But again John, DOES the amount of amps that can run through the 10 gauge wires with the new higher frying alternator meet standard electrical practices? That is the more important question.

What constitutes "a higher frying alternator"? One that can pass higher current to fry other loads, or one capable of frying itself such that it it is likely that a lower resistance fault path to the battery will result?

The fusible link protects against any short circuit in the wiring to the alternator, or a short within the alternator. The link is also the last measure of protection within the distribution system. This will be the requirement to be satisfied first, in any official wiring practice or regulation.

Conversely a healthy alternator will be protected, to some extent against overload, but only against an overload due to a short, or partial short, at the battery or within the associated wiring. That is if the wiring is as per the manuals. The fusing within the distribution system protects the alternator from overload in that direction.

[svxcess]

.
My alternator wiring modification has given me no problems at all without a fuse in the circuit. The 4 gauge power wire is securely fastened and protected by its location from any sort of normal mishap.

However, in case of a severe front end collision, there is the possibility that the integrity of that wire may be comprimised. If the power wire became cut or broken, the battery could instantly send between 800-1000A through that wire directly to frame or engine ground, which is bad.

I finally added a 175A Mega-Fuse into the charging wire circuit, close to the battery. If something does short, the fuse will immediately blow, interrupting the battery current and protecting its components. I will start with a 175A fuse and use it for a month. If all goes well, I will drop down to 150A, 125A and maybe as low as 100A.

The connections were power-crimped, soldered and insulated with adhesive shrnk-wrap

In case of an accident which caused a fire, the insurance company could not deny the claim as every due safety precaution was researched and taken.

I know this addition makes Trevor very happy. I feel more relieved to know that my electrical system is safer than it was yesterday.
.

[Trevor]

.
Excellent set up to cover a high-output alternator and very nicely done.

I am sure you will be able to reduce the fuse rating in order to gain absolute maximum protection. Please report back when your worthwhile experiments in this regard are completed. You have put in a lot of valuable effort into finding the best possible available components.

N.B. Make sure everything goes in the How-to section and replaces the very dodgy so called, "alternator upgrade" stuff.

[svxcess]

.

I thik so as well. According to the time/current characteristics of this fuse, I could go down to 100A easily. If the alternator were to put out its maximum current of 160A, the fuse would handle that "spike" for 10000 seconds before blowing. Going up to 125A would let it handle that same current output for more than 1000 seconds (16 minutes plus) This is the black line at the left

The black line towards the right of the chart show the 1000A range of current the battery is capable of. If the wire were to short to ground, the 100A would blow the quickest (at 6/100 of a second) while the 125A would blow at 1/10 second. The 175A would blow the slowest at 1/3 of a second

According to this chart, I think a 125A would be the most desirable.

The high-output alternator is capable of producing continuous power, without ill effects, at 80% of its 160A rating. That is 128A (more than enough for our electrical demands)

.

[svxcess]

Originally Posted by Trevor

N.B. Make sure everything goes in the how too section and replaces the very dodgy so called, "alternator upgrade" Stuff.

I have the complete documentation and procedure, including many photos and links to materials in a Word Document. Too large to upload to the network.

Maniac Electric Motors (makers of the SVX high-output alternator) have added my previous version, without the fuse, to their website as a model of how to do additional heavy gauge wiring and fusing. They have my latest one and are converting it to a .pdf file for easier loading. Once they put it on their website, I can download it and post post a direct link to it as well. I will send a copy to Earl to put in the How-To documents.

For those who don't want to do the new configuration (single power wire) mod that I did, the document will still address the fuse issue of the original "upgrade", as well as links for better cable and connectors.

The only thing not in there is the replacing of the 2 white wires that run inside the black plastic channel. Just a matter of cutting them back and adding new lengths and connectors to replace the aging, brittle ones. This still keeps the original electrical design and adds the heavier additional wires that a H/O alternator requires.

.

[svxcess]

'

The NEW alternator wiring configuration V.4 is now online at Maniac Electric Motors. It is a.pdf file which you can open and then save a copy on your computer for future reference.

http://lib.store.yahoo.net/lib/yhst-...adeWireSVX.pdf


I will make sure that Earl knows to put this into the How-To Documents as a newer version.

.