W210 CDI E320 Alternator -Full Load Amps ?

[datripsta]

Does anyone know the full load drawn from my alternator if all electricals are drawing current and the capacity of the current cable from alternator routed through what ever systems to the battery. I see a 200 amp fuse which suggests its ~190 amp capacity ?

I've seen 190 amp alternators on ebay sold factory fit options but not sure if they fit on the OM613 engine in my car.

Im looking to see if I have any spare capacity to upgrade audio system. Car has an amp but I believe its non bose. I'll be installing a new audio set up. New cables ,speakers, amp, head unit ( probably going with Nexus 7 gen 2 tablet with USB DAC as head unit ) etc... factory audio equipment will be disconnected or removed including Comand 2.0 unit, hands free phone and linguatronic.

Not bought any replacement bits yet and not looking to go crazy but want to ensure I don't kill the electrical system if I run an amp which needs 60 amps peak which in reality is easily done with a 5 way amp output to a 4.1 system. That said i'll probably never get to pulling full power but maybe running system at 50% more likely. A good number of quality amps on ebay going for reasonable money and these quality maps do pull a fair few amps even at 50% use.

I did the maths on a 2 amp system. One for sub and the other for all 4 door speakers run in active x-over config ( 4 mids 4 tweeters ). I calculate a 120 amp load! I then decided dissipate the cost being within rage if I buy used quality amps its way OTT for my needs. Thats what got me to thinking its easier to work back from any spare capacity the alternator has and tailor the system to the capacity.

Car is 2001 Estate E320 CDI Avantgarde.

MB online EPC Shows 150 amp alternator fitted to my car. I read 150 would be the cold output and can't find the hot output value which would be the best starting point.

Things installed that might not be standard that draw current:

Climate Control unit
Electric Sunroof
Electric, heated, cooled, contour seats both driver and passenger
Xenon Lights
Auto Dim mirrors
Parameter Steering
Parktronic
All interior bulbs changes to LED

Sorry for the long post and I hope I got all the detail down to answer any questions.

Thanks as always

DT

 

[Ted]

Pop a high current ammeter into the main battery feed and switch all of the consumables on.
This should give a fairly accurate answer.

I seriously doubt you will ever draw 1.5Kw from your amps over a long period of time, however you will obviously need to cable up to accommodate the maximum level of current draw.

 

[V12]

Lots of things to factor in here.

1. you will never be drawing 50amps at normal listening levels, try 10-20 amps.

2. You are drawing power from the battery, not the alternator. As a peak in the music is played, it may draw 20amps for a fraction of a second but then give the alternator time to recover the battery in time for the next peak.
I can't remember the exact calculations behind it but you only need a fraction of what you think you need.

3. Mercedes properly cable their cars to handle a lot more than they ever will need to.

Most of the options on your car don't draw much current. The one thing that can draw a lot of power is the water booster heater located by the expansion tank. I would only worry about some sort of upgrade if you do lots of very short trips, in the dark & cold, with your music blasting at full volume.

I have massive amps (can theoretically draw 240amps) fitted in my car and have not upgraded any cabling, alternator or battery and it has run absolutely fine for years now.

 

[bob6600]

There are 2 types of alternator for your car, one is a 150A Bosch and the other is a 190A Delphi unit. You need to physically see what is on the car as EPC will show both.

You need to get the correct one as the mountings are completely different and you cannot fit the wrong one

 

[datripsta]

thanks guys - Ill try to get under car in next few days and check out the alternator. Just went on EPC and indeed there are two options I messed up by clicking the number for the bosch unit ...

Assuming I do have the 150 amp Bosch. Is it possible to change from a Bosch to a Delphi - Can the brackets be changed or is the block cast to fit one or the other only.

I do a lot of short trips ( just under 5 miles each way ) to work 5 days a week and in the winter it can easily get to minus 15 here. That said its very true I wont be going round like some kid in a Nova SR hammering out basslines at windscreen breaking levels. I want good quality clean sound but keep my hearing for older age

So if I have the 190 amp alternator already am I likely to have less of an issue ?

 

[V12]

Indeed, 190A will be better than 150A. I'm pretty sure they both fit without issue but I had previously thought that the 190A was for the 320cdi and the 150A was fitted to the 220cdi. I could be well wrong here though.
I know my S class has the 190A and it doesn't struggle at all.

Make sure your battery is a good quality one and healthy.
There is a nifty snap-on tool that I borrow from a local garage which gives a percentage of the life left in a battery. They advised me that anything under 90% life should be changed on these bigger Mercs with high electrical drain.
Last winter my 4 year old battery was cranking slightly slower than I liked when it got really cold, when we checked it had 85% life but was still doing the job (just). It was a cheaper brand of battery that the previous owner had fitted. I changed it for a quality Varta battery and the cranking speed increased. The stronger battery will help the alternator as it will not demand so much current after a high draw (like starting the car).

Perhaps check the float voltage of your battery once a week during the winter and report if the sound system is slowly draining the battery.

 

[bob6600]

I'm sure you have the 190A as the date shows it was fitted from 31/05/2000

 

[datripsta]

I looked at the car today - it does look like a 190A version but I cant see clearly to be 100%

@ V12 - did you earth all your amps with separate wires or run all to a dist box and one large cable to earth. Did you have any issues with ground loops. Im going out to get cables tomorrow and cant seem to find a 3 way splitter so might just go with 3 cables anyway.

 

[V12]

Distro box for me. I've never had ground loop issues in a merc. The existing cabling and termination points are so much better quality than anything in a french car or most other cars for that matter.
In the UK I use CPC to order all my cables, some of the local trade places are ok, but they rarely stock every piece I want. Retail places like Halfords are very expensive and most of their stuff isn't very good quality anyway.