Alan

So jp those are the combo fuseholders both ATC & ATM fit?

20A limit though right? I do think it looks pretty good

Alan

jpitman2

The other upside of blade fuse sockets is you can easily use an ammeter like this - plugs into a blade fuse holder:-
http://www.jaycar.com.au/productView.asp?ID=QP2257
There is also a cheaper 20A version.
jp 83 Euro S AT 54k

jpitman2

Another reason to do this. Tale recently posted to landsharkoz, but bears repeating.
A few years ago I replace the fuel pump relay. A few weeks ago, I went to start it, no dice. After a bit checking fuses, pulled the pump relay, put back in the original unit, fired right up. That replacement relay didnt last very long I thought. Went for a run, 40 mins out, died. Pump relay was hot to the touch. Bridged the relay, got home. mmmmmm. put in a generic 53 relay, pump started at turn on, I though OK, that will get me around until I can replace it. Went to start it today, brief catch, stopped. Bridged the pump relay , no pump....wriggled fuse 13 (listed by 928 specialist chart as pump), nothing. bridged releay again, and caught a spark out the corner of my eye, too far to the right to be 13....plugged the releay bridge in, wriggled fuses rightwards...fuse 22! Loose - no pressure on the ends, and the contact caps are not at all bright, or marked by contact. Put in one of my blade fuse holders, now have pump reliably. Went to start it, but could only get small catches, wouldnt take any throttle with the generic 53 relay. Put the OLD relay in, caught and ran fine right away. Looks like a 53 isnt a usable temporary fix, at least at a cold start, with CIS. Now I suspect that the relay failures have been caused by poor contact at the fuses causing an increase in current .....
About to send out some test fuse holders to a couple of users here, and a pair to Alan next week.
Looks like I have to use an earlier NY fuse chart, or at least the list in the Owner's Manual.
jp 83 Euro S AT 54k

Jadz928

I'm with ya, John. I don't believe the 53 relays are 'cutting it' on the CIS cars.
Had a very similar experience to the one you shared.

I like your mini-blade fuse block idea, in particular, for isolated single fuse concerns (like the #22 FP).
Took me a little to figure out how you executed it, but get it now. I'm a little concerned about solder break where the wide male terminal solders to the block.

I checked into design feasibility of using the std. blade fuse, and more of them in a row (5 or 10), mounted to a PCB. Seemed quite possibly except for there are no "off the shelf" wide terminals (.32") that work in a thru-hole PCB design. Would need a custom solution (progressive die stamping) for a custom terminal.
Not out of the question, just not in the cards for me right now.

Like I said, I really like what you are doing. The torpedo fuses are riddled with potential problems.

KLVA

I think this is on the right track...maybe the lower connector could be side mount to move the mini blade holder to sit lower in the fuse panel

jpitman2

Attachment of the 5/16 female to the holder - I am soldering the brass female to the two pins on the bottom of the block, with it butted up to the block. I hope this will relieve any load on the solder joint on insertion. I have R&R'd some blocks several times with no signs of fragility so far, so I am pretty happy with that side.
I have looked at a way to fit this large socket on the end of the block, so it can sit lower on CE board but no luck so far. The range of 5/16 females available here is 1 type - 'flag' or made for side entry of the wire lead, which limits what I can try - if anybody in US can find other shapes of 5/16 females, please advise where, part no etc.
FWIW, height is NOT an issue - tall relays like the fuel pump have made sure of that.
If I make an L shaped piece of brass to sodler to the pins on the bottom and run around the end to solder the female connector to, the block is getting longer, and I will have problems getting the other end to fit. Havent given up here yet though.
Problem with 30A rated holders is they have the pins underneath in line down the holder, not to the sides, which may make life difficult. Waiting on some samples to try out now. Problem with buying small volumes is the postage overpowers the product cost - one place I can get several things from has a $15 postage minimum on orders < $200.....PITA!
jp 83 Euro S AT 54k

jpitman2

Pics to show absence of height issues . The relay is intensive washer, which is usually down in a lower socket, but you get the idea.
stad size blade, then low profile, in same holder.
jp

jpitman2

How about this version? Next chance I will cut back the excess brass underneath. It requires some levering of the large bottom blade away from the plastic ridge, to clear the curved part of the female to engage the blade, but once its in, its has to be levered out, as there is so little to grip. Very stable when fitting and removing the fuse. This small holder will only take mini-blade fuses. The large brown part is the fuse head.
jp 83 Euro S AT 54k

Alan

You know jp I was going to propose something like that and you beat me to it... I think that is it !

Getting it down ~flush makes it look much better...

Did you use a piggy back blade connector for that end? - I was looking for one of these in the 5/16 (~7.9mm) size - couldn't find one anywhere.

Nicely done!

Alan

jpitman2

The 5/16 female is a 'flag' type as in here:-
http://www.vehicle-wiring-products.e...hoto/00513.jpg
with the side cut off - only connector I could find in that size.
The 1/4 connector is an uninsulated piggy back with the second male broken off - again, only way I could get a female with enough on the end to solder to the holder. One up side is that its easy to solder the 5/16 to the holder, as I can fit the 2 small lugs on the holder through a gap in the female, bend them over, and just apply the iron - the other types take three steady hands to keep thing lined up at the correct angles.
The down side of this configuration is that it will probably only take a few R&R of the holder for flexing to break the 5/16 female off at the 90deg bend. If it works though, it shouldnt need R&R at all. Also, holders short enough to fit will only accept Mini-blade fuses.

Do you want me to send you a sample of each approach, or could you knock some up yourself ? I think I posted above links to the keystone parts used.
I hope to have some 30A holders to try this week....
jp 83 Euro S AT 54k

PS Please assume that all the ideas and pics here are accompanied by 'Pat Applied for, Regd Design' etc.... :-)

Alan

JP no need really - at this point I have about 3 late model CE panels but no early ones to try this on - though I may look to pick one up now?

To me thats obvious... !!

jpitman2

Had a chance to take advantage of the blade fuse holder today - checked fuel pump current with the digital blade fuse ammeter - removed fuse, plugged ammeter into fuse holder, bridged the relay - 7A. Easy.

Update - its very difficult to find a holder that will work here rated higher than 20A .... So I am going to put a new holder in some of the 25A positions, and check with the digital ammeter what the real currents are. The ammeter has a fuse in its connection, so I am going to use a 20A fuse there, and see what is actually flowing. The chart lists as 25A fuses - Seats, a/c fan, heater fan, Headlight motor, windows&central locking, rear defroster.
I have a dual electric fan system now, with each fan on a separate fuse, the first coming off the a/c fan circuit. I doubt that will need 25A, but will check what it pulls. To me, that one, windows and the headlight motor would be the major show stoppers, so I will check them first. If I see < 15A I plan to fit some new blade holders with 20A fuses, and see how we go.

jp 83 Euro S AT 54k

RoeblinGroup

Hi, I'm a noob, I have issues with my car losing power when I'm idling. Can anyone help? I have a 1984 Porsche 928s automatic. I have many issues with my car and I have a lot of questions.

dr bob

Go ahead and start a thread on your specific problems if you haven't been able to find answers via the search function. This thread deals with a specific concern about converting old-style fuse and relay panels to later blade-style fuses. It's unlikely that your low-speed charging problems are caused by a fuse-panel conversion....

jpitman2

Here is my process for the low profile holder, with the type that takes normal blades, minis, or low profile fuses - Keystone No 3557-2, 19.8mm long.
Brass flag type 5/16 - cut the flag off, push down the left side of the part thats meant to crimp the wire, push it through and cut it off, and push the other side down flat; nick the sides of the top above the blade socket, bend over near 90 degrees.
1/4" female starts off as a 'piggy back' - 1 male to 2; break off/cut the top male end; cut half the other male off so the female can seat fully home on the board; set the stub paralell to the female - this stub is what we will solder to the fuse holder.
File a bevel on the end bottom corner of the fuse holder where the brass 5/16 female will bend around the corner - reduces the sharpness of the bend needed. The hardest part for me is getting a good coating of solder on the small legs of the holder. Wriggle the gap in the brass 5/16 over the two holder pins, and bend the pins flat (outwards), solder. Note that the fuse sockets are a little loose in the holder, so make sure they are pushed home from the top to give the longest possible pins out the bottom. I hold this assembly vertical by the already soldered end (small vise grips), and introduce the 1/4" female (already tinned, held with a jewellers driver) to the pins , and solder. The 5/16 male blade on the board may need a little levering away from the plastic board to clear the curl of the socket.
There is a smaller holder (Keystone 3588) that is 16mm long, only takes mini-blade fuses. Process is almost identical, except the 1/4" female is completely bare of any extra metal, and is soldered directly to the holder pins, on the other side - the two sockets need to be 13-14mm apart to line up with those on the board.
Sat down at the bench the other night and got 5 of these done in 10-15 mins, so once you have all the parts, and can solder a bit, its not too hard.

I now have fuses 5,6,8,16 fitted with low profiles. 22 (fuel pump) has a high rise unit for the moment. No problems so far, but not a lot of time on them yet. I plan to fit these to all the 16A fuse places, and then test some 20A blades in 25A sites, and see is any blow. So far I dont think its worth doing the 8A sites, at least until I get time to sit down and make a whole bunch of replacements.
jp 83 Euro S AT 54k