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Thu Jun 07, 2012 7:39 pm

Electrical geniuses.....

I am attempting to install an ATO style Fuse Block in my Beetle. Question... I noticed that it appears that several of the connections on the old fuse block are cross-connected (seems to be there are several pairs of connections within the 10 fuses). Is this observation accurate? If so I guess I'll have to make jumper wires to make the cross connections...

Hope this question makes sense. Maybe I should just make some test leads and see if the apparently paired connections really are....

Thanks in advance for any help.

Thu Jun 07, 2012 11:08 pm

Yes, with a 10-fuse fusebox you have 5 grouped pairs. Terminal 15 (hot with key on), terminal 56a (high beams), terminal 56b (low beams), terminal 58 (parking lights), and terminal 30 (hot all the time).

Fri Jun 08, 2012 5:39 am

Thanks so much for the explanation. I'll see if I can put this info to good use....one wire at a time!

Fri Jun 08, 2012 6:57 am

a Great IDEA. and do tell the extent of changes and gauge wire used.
click tech + wiring, + type1 and year
see that fuse box.
see those heavy black lines
those are cross bars.

and the china fuse boxes (dont buy one) have some missing. CIP1 crap.

you need to "daisy chain" these.
how to do that?, if your new block don't have 2 pins each side
go to digikey.com

type in :A27891-ND (AMP faston Y splitters)

they sell the orig, VW AMP lugs too.. ask..... both sizes too....

Fri Jun 08, 2012 8:10 pm

You need to be careful how you make the junction. Since the ATO fuses don't come in an 8A version (that I could find) you will probably use a 7.5A or 10A. The junction will carry twice the load. Be sure it can handle the 15A or 20A load.
The original fuse box had a very robust bar connecting the two fuses (three on some later fuse boxes).

Sat Jun 09, 2012 6:35 am

WOW! You guys are great....the info is invaluable.

I also couldn't find the 8 amp fuses, so I went with the 10 amp.

I chained each two fuse sections with a short (2.5") loop of #18 wire at one side of the fuse block and used spade, push-on adapters that have either one or two male spades as necessary.

I went with the #18 wire as I read that it could handle a max of 25 amps.
If that's not correct I can re-make with #16 or 14....

I have another connection question. All the wiring diagrams I have seen don't show (at least that I can follow), how to wire the Fuel Guage Vibrator to the Fuel Guage. I must be missing something.

Thanks again in advance.

Sat Jun 09, 2012 6:37 am

not sure about that, 16amps is ok UL310, pass for this part. (its only a short daisy chain too)
http://www.te.com/catalog/pn/en/61765-2?RQPN=61765-2#features

but we dont have his plan!
the new design.
lots of details to a design besides, what is posted is not complete input. My assumption is to perpetuate the FASTON IDEA !
schematic, and BOM. is what i need to review it.... just like at work.

if i was doing this (why ?) id do go digikey.com
way1
and wire in new barrier blocks that have 4 faston prongs
on each side, then wire the fuse box into one side of it.
and wire gauge to match. I have control this way.
+
and my new fuse in the #30 line at battery.
and my new #15 IGNITION SAE rated thermal breaker.(resets with loss of short)

yes, the buss bar must be robust. This connectors are rated high see the data book.

one could abandon faston , technology and revert to ring lugs.
the don't fall off. or go bad so easy. but the orig. was cheap way...

ive worked some old transportation system that had that (trains) always failing all the time (pay dirt)
and going to ring lugs. solved all the intermittent, (hard data proof ,too)

This is why i just replaced the bad one on mine. (improved too)

if FASTON (TM) tech, is a must? VW used AMP connectors.. by same name then.

the TE Connectivity line (AMP>then Tyco) has huge, diversity
you can buy barrier block buss bars. that branch from there with
discrete Faston for barrier screws. (custom end to end)

the current rating today for faston's "AMP corp"
is today revised,
UL 310 specification or Catalog #82004. (test condition)

the vw connectors can all be upgraded to same with tin.
the raw brass, sucks. stock. "corrosion happens"

i get mine at Digitkey, all. in tin.

the stock car has .250 Faston's up front, you could up grade to the wider faston
for the main feed to the fuse box , as VW failed to correct.
the 250 series is rated at (.25 pitch") per UL310 rules. as.
(eg the #30 DIN wire is about 10 gage. 6mm^2 . as a single case)
and that wire on a 250 series is rated
at 24amps continuous, and 48 intermittent (54F degr, rise rules per 310 above.)
the larger AMP connector on my REG , stock is rated far higher.
ask.
the part has higher rating with tin, and even more in silver.

here is the spec page. go ahead and noodle that and decide.

http://www.te.com/commerce/DocumentDelivery/DDECon...DocLang=EN

there are better ways and system.
that is for SURE.

------------------------ horror 2---------------------------------------------
this is not 1968
back then they over fused.
if you look at the wire spec, and the fuse ratings. its illegal today.
for 2 reason, heat, and piss poor insulation.
we have a 54F heat rise rule today UL 310 so that changes the rules.

and those ATO fuses are sized for AWG , Amercian wire gauge applications
not DIN spec. wire.
so he never said what spec wire he ran, AWG or DIN? nor the gage.
i bet on AWG.
and he can run 10amp fuses if you uses the correct AWG gage wire.

lots of details:
needs (load)?
heat? (200f parked in the sun) easy.
wire lengths? The 10foot rule is important. (down 1 AWG size)
insulation type? (much better today, vast choices)
wires bundled?
using Tyco AMP, Faston Series 250s, are you?
vibration (ouch) on cars it's bad.?
using AWG wire.?
using, ATO UL USA fuses?
exposure to corrosive elements?
end. im sure i left some out. but as they say , the devils in those details.

those are the variables. unsaid.

Sat Jun 09, 2012 8:20 am

Here's the way I did this conversion on my '74 Thing which also uses a 10 fuse panel (5 pairs).
This writeup, originally for The Thing-Type 181 Registry Magazine, is at least 15 years old; eventually I replaced the fuses with German 8 and 16 amp ATO fuses which I grabbed from junkyard Rabbits. 8 and 16 amp ATO's are hard to find in the US.

Good luck, Mondshine

Sat Jun 09, 2012 8:27 am

18 gage wire (AWG) not DIN, our posts tied.
18 is good for 5 amps, in cars and boats. it is very tiny wire.
the bug runs 18g, DIN.75mm in the parking lamps. a 1amp load.

do not get confused by wire current ratings (12v cars and boats not homes and machinery)
they vary by many factors
this is 12vdc.
Most off the shelf wire is junk, very poor insulation.
But can work well if you, use hefty wire. and grommets.
and one more factor, cars sit at 200F temperatures.

most car builder avoid 18G. totally, and use 16 min.
VW actual:
the vw used some small , DIN .5mm^2 wire. up to 6.0mm^2
(ignoring the starter of course)

the smallest input to fuse block wire is DIN 1.5mm , this is near 15gage AWG.
there is no 15gage on your shelf. so you go to 14, here. not smaller.

the largest fuse input is 4.0mm^2 AWG that be 11 gage, again,
so in this case you use, 10gage AWG
never drop wire size when converting.

after careful searching for good examples, (not engineering tables)
see this
see top row on left for 12v,
use the 10 foot row.
use that and you will never fail
see comments below in linked page,for engine bay rules.

http://bestboatwire.com/catalog/includes/languages/english/wire_gauge_chart.html

do not use wire that drops more than 0.5vdc at any point.
starters have different rules, and less drop on the power feeds.

Sat Jun 09, 2012 8:31 am

yes the Little fuse panel is popular
but the wire gauge is important.
no overfusing. no undersized wires.
use quality high temp wire. not china wire. (no spec)

Sat Jun 09, 2012 12:38 pm

Still wanting (simple to understand) info on the wiring for the Fuel system Vibrator and Fuel Guage......seriously. To me the wiring diagrams are barely usable and in some areas plain confusing. Obviously I'm no electrician, but I can wire up almost anything one wire at a time.

Thanks again.

Sat Jun 09, 2012 12:49 pm

Here's the back of the Speedometer:

Most vibrators plug directly to one of the lugs in the gauge itself.
Notice how the vibrator case is attached to the back the speedometer.
The other vibrator lug is connected to (terminal 15 of) the ignition switch and will show +12V with the ignition switched on.
The other lug of the gauge is connected to the sending unit in the fuel tank.
Good luck, Mondshine

Sat Jun 09, 2012 4:05 pm

Once again I gotta say WOW! That's the way the wiring diagrams should all be! Even an electrical clown like me can understand it and maybe get it right....

Muchas Gracias!!!

Sun Jun 10, 2012 12:11 am

bfreckman wrote: I chained each two fuse sections with a short (2.5") loop of #18 wire at one side of the fuse block and used spade, push-on adapters that have either one or two male spades as necessary.

I went with the #18 wire as I read that it could handle a max of 25 amps.
If that's not correct I can re-make with #16 or 14....
I would go with 14AWG as a MINIMUM. I actually think modshine's diagram shows he went with a 10AWG wire which is even better/safer.

Sun Jun 10, 2012 12:19 am

If it hasn't been done already, replace the "vibrator" with a new replacement unit that uses a resistor to drop the voltage to 10 volts. According to my VW parts guy, when the old style units go bad they send 12 volts directly to the gauge and fry it. When the new ones go bad, they send 0 volts to the gauge and save you $38. I just replaced both in mine, gauge first. He warned me that if it started to head to full rather rapidly when I knew it was not full that the regulator (or vibrator) was also bad... which it did and it was so I disconnected quick and replaced with the $12 new style unit. The old units are an all metal can, the new ones look the same but have a plastic base.

W

Sun Jun 10, 2012 9:38 am

Where would one purchase the "new" Fuel Vibrator and what to ask for??? Or are the ones being supplied as any replacement today the correct type?

Bill

Sun Jun 10, 2012 10:17 am

I believe all the current replacements are the new style. Here's some pics. The do-hicky on the old one is a noise suppressor which isn't needed on the new style. Looks like I was wrong on the price and physical description (memory fails). No brand name anywhere but the number on the box may help. I can ask next time I'm there also.

The box says "speedo/v reg." but, of course, it's for the fuel gauge and only mounts on the speedo housing. Not marked with country of origin either but the new fuel gauge I bought at the same place says "www.jpgroup.dk" "Electrix" and "Distributed by Denmark <> Germany"

Hope this is useful info.

I wasn't very happy with the gauge itself because the dial had been mounted crooked and didn't match my original exactly. I don't recommend doing this but I (VERY CAREFULLY) removed the new dial and installed my original in it's place. Now it looks original except the needle is bright white and not faded.

W

Sun Jun 10, 2012 2:43 pm

I've seen both that style of Voltage Regulator (and it's not a resistor in there... unless they've changed them, there's a Zener Diode and a light bulb inside) and even seen traditional 3-tab electronic voltage regulators used there.

Sun Jun 10, 2012 5:32 pm

Interesting.. makes me want to pop this new one open and see whats inside it. I was just going by what my buddy at the VW shop who sold it to me said about the resistor. I went to school with him and he's been into bugs as long as I remember but ya never know, he could be wrong.

W