Alternator Upgrade

Ok im doing something seriously wrong here, though I will be over the moon if im not.

Tester set to 100 range, dc selected and zeroed before use, live cable between clamps and centered as best as possible.

Reading is never higher than 20 amps, but more often than not around 10 to 14 amps. Reason im questioning it so much is with all lights on, ac full blast the vw live cable is only reading at around 14 amps.

Got to be doing something wrong here!


Take a picture of what wire your clamping, ill do the same test..

id recommend putting your amp-clamp around the MAIN BLACK GROUND CABLE ON THE BATTERY NEG POST

for a full system readout.

if your clamping on of the red cables you might be missing current going down other cables....
 
just had a look under the bonnet on mine...

you have one main neg (black) and two big reds (positive),

one red is the starter motor feed and the other is the link cable to the main junction box under the battery which is then connected to the alternator on a seperate cable.

so it looks like your metering out the main battery charge current..... as the battery charges you will see a decrease in current.

to meter out what the van is drawing from the alternator i think we need to get down to the main power distribution box below the battery....

basically the van is drawing current from the alternator via the junction box . . . . . but "at" the battery we are only seeing the "charge current going into the battery when the engine is running"..


or . . . . . .


another option is to clamp the main black ground cable at the battery post .... WITH THE ENGINE OFF.


this will ensure that any electrical loads have to draw current from the battery, which means you will be able to meter it out properly.

Note: AC will only work when the engine is running,

same with, front screen demister, leisure battery split charge..... not sure about heated seats?
 
Ok im doing something seriously wrong here, though I will be over the moon if im not.

Tester set to 100 range, dc selected and zeroed before use, live cable between clamps and centered as best as possible.

Reading is never higher than 20 amps, but more often than not around 10 to 14 amps. Reason im questioning it so much is with all lights on, ac full blast the vw live cable is only reading at around 14 amps.

Got to be doing something wrong here!
Engine running?
 
If I remember correctly you just purchased a VCDS. It is a good tool also for monitoring current going in/out of (only) main battery. Module 61, advanced measurement values - battery current, battery voltage, etc.

The VCDS is capable of taking 6-7 measurements/second if there is a need to record events. Another good thing is that the module 61 is "alive" and communicationg with the VCDS even without ignition on so it's easy to monitor how the systems in the van get up.
 
Yep got a vcds device so will give that a try tomorrow.

Putting the clamp on the negative lead certainly did the job (and this time I turned the engine off). Plus cheers for the video and explain things to me in it :)

With just the radio on it averages at around 28 amps and peaks at about 39 amps. So working on 12 volts that’s in the 300 to 500 watts range which sound about right, less than I thought, but realistic. Maybe I can get away with not needing a 2nd battery after all :)
 
Well. This was the first vid....

But the readouts are obviously Totaly wrong...

We was metering out only the battery charging current. But I thought I'd post it anyway.

So just for a laugh here it is..... but we are only metering battery charge current.....nothing else.




Happy Thursday peeps.
 
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Do you always pull a funny face at the start of your videos
Love the freeze frame :)
 
Well the new 800 watts into 1 ohms is in (bar setting gains and tiding up) :)

Had a quick go with her and she pulled 52 amps which the van seems to be happy with (so around 90 amps total), just used my old 10w3 sub for now, and its taken 3 days of my life so far, but boy is it satisfying to do. :) RCA leads are just temp for now to some correct size ones come tomorrow.

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Downside is that I have noticed this. Is this normal or do I need to be worried? I have a flettner, but even so its surprised me. Good 5mm gap between roof and support
IMG_0238.jpgIMG_0240.jpg. :(
 
Well the new 800 watts into 1 ohms is in (bar setting gains and tiding up) :)

Had a quick go with her and she pulled 52 amps which the van seems to be happy with (so around 90 amps total), just used my old 10w3 sub for now, and its taken 3 days of my life so far, but boy is it satisfying to do. :) RCA leads are just temp for now to some correct size ones come tomorrow.

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Looking good.

Keep the pics coming
 
Thank... for that :) that gap really had me worried

Will do, clips have arrived so back to tiding up shortly

yeh strange about the gap . . . . .

as for wattage . . . . i normally esitimate 100amp supply per 1000w load.

so for either inverters or amplifiers id install supply feeds like this:

500w/ 50A
1000w/ 100A
1500w/ 150A
2000w/ 200A
3000w/ 2x150A

but as you have now seen these are theoretical max currents.

so volt drop and in efficiency's play into it as you have now seen with your new meter.

so a 1000w inveter will happily tick over drawing 50-80 amps with a moderate load..... but will very rarely surge to 100a or over.

the best thing you can do is run proper beefy power cable and fuse appropriately.

these are on my todo list (Kicker 15" L7 solo baric) on a kenwood monoblock and kenwood 2chnl running mids and tops up front. . . . . . .

just thrown in for now as a place saver, but will need to cut out the bulkhead again.(behind drivers seat)

22.jpg
 
Done, well apart from doing the rca leads and refitting the ceiling trim. :laugh:

Dam impressed what a cheap sub with some quality amplification behind it can do :) She may be 7 years old, but there is plenty of life left in her
 
Done, well apart from doing the rca leads and refitting the ceiling trim. :laugh:

Dam impressed what a cheap sub with some quality amplification behind it can do :) She may be 7 years old, but there is plenty of life left in her


JL Audio make some good gear,

you not got a speaker grill for it?
 
Love the pic :) makes me feel not so bad about the thick layer of dirt on my sub now :laugh:

Dam but they're huge, what wattage do they kick out? Must weigh a tonne which is always a good sign :)

Your a braver man than me when it comes to cutting your bulkhead (I swore I would never do that again), still the things we do for sound... With the cut bulkhead and the stand already done it will look dam nice, you will need to post a pic when you are all done as I'm curious how it will look finished of :)

Cable wise I've got 0 AWG going to the fuse block and then 4 AWG running to the new amp, the 4 awg is 5m long which is longer than I would like (dam big amp), but it's within its rating. Just watch the power cables you have used, as I don't see any writing on the cable which means its not true AWG cable, probably not an issue if the load isn't too high or the run not too long, but something to watch if it is as it gets hotter than AWG marked cable
 
JL Audio make some good gear,

you not got a speaker grill for it?
Leaning towards getting a JL 10W6 when I have built the funds up again as my old W3 has really impressed me, but there is no rush on that, I would love a w7 but I just don't have the volume for one... trying to keep the van usable really does bring limitations.

Nope, the sub before was fitted in the roof space above the cab as it was a high roof, so there was no need. I'll sort out a grill for the new sub, but as long as I'm careful there isn't much point with the current one (unless I decide to keep it), besides with it just behind the sliding door its fairly safe to then. Still can't get over the difference to the sub that moving it from an undersized to correct size enclosure has made, must have double if not tripled its volume output.
 
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