Hi Fred

Please add my name to your list.

Thanks

Carl

Add me to the list....

Me to please

Has anyone made one of these for the three fuse panel in the engine compartment, that would be more my speed?

Add me to the list.

interested, 3.2 1989
At the same time I'm also looking at putting in a headlight relay system.

Fred,
I see this in a 2007 Hella cat.
H842911021 Fuse box with screw contacts – 4 fuses
62911, looks like they have or had one for 12 fuses also. Page 62
I don't know if these ever existed.

Fred,
I also see this torx screw terminated ATO block.
GEP Power Products - ATO Blade Type Fuse Panels
Just FYI while I'm looking around for relays with diode suppression.http://forums.pelicanparts.com/uploa...1322528691.jpg

Nice work Fred.


I decided to upgrade my cars after reading an ATO upgrade thread last year.

Your kit will make this a reality. Please put my name on your list for a kit.

Thanks

Fred, FYI in case this is of interest.
More info. on this GEP product.
I called , the 3 fuse unit is $4.12 ea., 6 fuse is $5.21 ea.
Total height is 1.7", depth is 0.89" before fuse is installed, not sure how this will fit, I need to check.
I can't get these to come up on the ordering website so will need to call again, I'm tempted to get a couple 3 fuse units, all they have in stock at the moment.
The nice thing is that the wire connections are bare wire squeeze type, you don't need to crimp on a termination. I can give one a try in the engine compartment and see how they work.

On a slightly different subject regarding headlight relay type. I'm advised to use diode suppression featured relays, not sure what the JWest relays have. GEP has these as well along with the usual needed accessories if someone wants a DIY project.

ATO fuse holders.....
 

The only problem that I see with these fuse holders is that it will be difficult to build the necessary "jumpers" to tie two, three or four of the positions together to replicate the original fuse panel.

As to the diode equipped relays, I'm not sure why that would be necessary if two relays are used, one for the high beams and one for the low beams. Using two relays allows for a single jumper to be placed from fuse 5 or 6 to a relay for the low beam trigger wire with the opposing lead going to ground. The +12v lead from the battery would go to a fuse and then to the relay power term with the opposing terms connected to the headlight leads. On my fuse panels I use one of the extra fuse positions to protect the low beam power circuit and the second fuse position to protect the high beam power circuit. Hope this makes sense.

In a previous life I designed and built larger versions of these. Strips of metal can be cut in the shape of a "U" or "W" for "jumpers". Tinned copper or bare copper sheet works (can be coated with something if needed), takes very little material at these current levels.

Re. diodes - the comment regards that a relay without suppression puts a spike on the wire when the coil is de-energized. You can buy ISO form factor (this is what people are using) relays with diodes or resistors built in to avoid this. It might not be needed on an old Porsche but should not hurt and I would not use a non-suppressed relay on a new car. E.g. the fog light relay on a 1989 3.2 has a diode inside. That's what I was referring to. I don't understand the "two relays" train of thought.

Fuse block jumpers.....
 

I agree that you can build a jumper as you describe. However, how are you going to insulate it from accidental contact? I suppose that you could brush it with a rubber compound like the material that tools are dipped into but then you would need another connect point or points. Doesn't sound like good engineering to me.

I use two relays, one for low beams and one for high beams. The relays are usually rated to handle a given amp rating (20 amps for example). Since a 100 watt bulb would pull slightly over 8 amps, the relay should handle the load of two of the 100 watt bulbs. The second relay is for the low beams which, of course, would pull a lesser amount of amperage. As you said, the older Porsches are mostly mechanical and analog so a momentary voltage spike at what is sure to be very low amperage should not be a problem.

I've been watching this thread as I plan to update my '73 with a 997 kick-panel fuse box and relay holder and I thought I would share some things I found along the way. Especially the bridging of multiple fuses onto one power source.

My first thought was to just replace the existing fuse blocks of my '73 with these from Waytex, but I didn't like the spade terminals and how to bridge multiple fuses onto one power source.
http://order.waytekwire.com/productdetail2/M50/46084/FUSE%20BLOCK%20WITH%20COVER%20%2012%20FUSE/

Then I started looking around and found that MTA is an OEM builder for a whole bunch of manufactures. In their catalogs is some good stuff and they have bridged terminals, but...problem here is that they are in Italy and the distributer in the US has minimun purchase requirements. At least that was the story a while back.
MTA | Products

What the heck. I started looking at what Porsche has in the 996 and purchased a used fuse box with wiring from a wrecked car and and found that these ATO fuse holders and relay holders as well as the wiring is built by MTA and Leoni in Germany. The fuse holders and relay holders have MTA molded into them. They also have BMW and AUDI molded into them. The fuse box had a Leoni part number sticker and the wiring had Leoni molded into the insulation.

After disassembling the 996 fuse box, I did find a multitude of bridged terminals with different gauge wire.
http://forums.pelicanparts.com/uploa...1322617206.jpg
Contacting Leoni regarding the wire terminals was a waste of time. They have absolutely no desire to help. So I may have to splice into these terminals to connect several circuits into one power source. Each little terminal is spot welded onto a buss bar.

Back in the day, you used to be able to buy the terminals seperately from Porsche, but not for the newer cars. You can get the plastic components, but not the terminals. Then I went to the BMW dealer since they too have MTA and Leoni components and you could buy the terminals seperately. Woo Hoo! I'm onto something here. So I purchased a bunch of wire terminals from BMW and what you could get for the pre-89 Porsche and now have the necessary terminals I need, even for those used on the Maxi fuse.
http://forums.pelicanparts.com/uploa...1322617695.jpg

The cost of 996 or 997 fuse box components and/or relay panel components is relatively cheap. Here's the components I working with.
http://forums.pelicanparts.com/uploa...1322619017.jpg
http://forums.pelicanparts.com/uploa...1322619046.jpg

This is where I going with my project and thought I would share. Maybe Waytex, MTA or even BMW or Porsche can help with your electrical needs.

Excellent investigation, solves the input jumpering issue while remaining a clean design.

very interesting - I always knew the 996 was good for something...

On the 3.2 schematics I see multiple power "feed" wires coming from and going to the same places. I guess this avoids part numbers for bigger wires. Be advised in case you see this.
For example - two wires are showing from the starter to the engine compartment 3 fuse panel. I haven't confirmed on my car. From the looks of the above 996 arrangements, there may be fewer duplicate wires. Not sure if this is a better design, just different.

Porsche wiring using a common bus....
 

All of the Porsche wiring diagrams that I have examined show multiple wires attaching to the jumpered or common bus locations at the fuse panel. This is used in some cases to take non fused power to gauges, power windows, relays, etc. One wire is usually a +12v lead with the others being distribution wires. The leads pulling off of the bottom or out side of the fuse are usually those that pull enough current to warrant being fused. When condidering replacing a Porsche fuse panel, it is well advised to be certain that you understand where each wire goes and what it does. Before I replaced the fuse panel in my SC, I spent several days pouring over a factory wiring schematic to have that knowledge. The result was a conversion that worked the first time with no problems. In this case, knowledge and patience are your friends.

Good points.

I see in one of your pictures showing additional headlight relays that the relays have coil suppression either resistor or diode - so I would say you have that issue covered if people use your relays. This may be overkill as I've mentioned, might not be needed if there are no electronics upstream or connected that might be damaged. I've now driven my self nuts looking at relays - and at this point I'm looking at
Mini Relay
Part# V23234C1001X008 from Chiefenterprises. It is probably a Hella or Tyco. Has two #87 outputs so you don't need to splice a wire, also has a diode.

A bit more on the ATO fuse panel I mention above. They can be ordered with incoming jumpering or bussing as they call it. The engineer there sent me some more info. The increment is 3 positions that can be bussed. You can select where you want the connection position, right or left. This might work well in the engine compartment where I think the input is a common point but two wires are used. If I change I'll consider using both wires connected to the same point to reduce confusion for future owners or mechanics compared to running a new bigger wire.

I still need to understand in confirmed detail what the jumpering needs are for the trunk panel.

FYI, Leoni was the original supplier to Porsche all the way to the beginning. The original wires in my '66 have "Leoni" stamped into the insulation.