I have seen all sorts of answers, from various sites, on this, from 60A -150A and everything in-between.
Can't seem to find the specs of this.

I have a 2011 TDCi 2.2 with a 2015 2.2 engine (the original one was replaced in 2015 with a 2015 model.. Not sure if that means anything to do with alternator spec however)

Thanks so much.
 
sorry, that was the best reply i could give
i dont know the engine but yes there is probably a standard size.
it shouldnt be hard to get to
 
So I can understand what electrics I can add, (spot lights, fridge etc), And if I need a higher rated alternator installed.
Doesn't quite work like that though - maximum alternator capacity will only be reached at certain RPM or above - tick over is usually only sufficient to output about 1/3 the alternators maximum plated capacity.

So if you add big electrical loads the alternator will not keep up at idle, you need to be driving which is why many people go for twin alternators and dual batteries.

You don't get long out of an alternator running it at or near fully capacity, 150A is pretty serious at 14.4V is 2.2Kw. The voltage regulator is going to be HOT and the windings will be cooking. A duff battery can kill an alternator fairly quickly due to increased alt loading, so intentionally loading an alt with large loads can do the same - also note your battery will become a weak spot - the battery acts like a big buffer, if you run large loads and the vehicle slows or idles the battery is doing more work as the alt output drops - then you start to drive faster again and the large load coupled with the additional current to recharge the battery can then push the load up significantly.

Note it says 85/150A - that would suggest there are two options on these, probably varied by packages.

I'd work out what I wanted to fit then go from there. Always assume the factory charging and power system is not really up to much more than intended bar a few extras.
 
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Doesn't quite work like that though - maximum alternator capacity will only be reached at certain RPM or above - tick over is usually only sufficient to output about 1/3 the alternators maximum plated capacity.

So if you add big electrical loads the alternator will not keep up at idle, you need to be driving which is why many people go for twin alternators and dual batteries.

You don't get long out of an alternator running it at or near fully capacity, 150A is pretty serious at 14.4V is 2.2Kw. The voltage regulator is going to be HOT and the windings will be cooking. A duff battery can kill an alternator fairly quickly due to increased alt loading, so intentionally loading an alt with large loads can do the same - also note your battery will become a weak spot - the battery acts like a big buffer, if you run large loads and the vehicle slows or idles the battery is doing more work as the alt output drops - then you start to drive faster again and the large load coupled with the additional current to recharge the battery can then push the load up significantly.

Note it says 85/150A - that would suggest there are two options on these, probably varied by packages.

I'd work out what I wanted to fit then go from there. Always assume the factory charging and power system is not really up to much more than intended bar a few extras.

Ahh - I was afraid it was going to get complicated.

I guess all I want in the short-medium term is:

Spot lights x 2 in front of grill (Have bought some LED ones - no specs on them (Chinese stuff) - but I think they draw somewhere around 24A) a bit of a guess
Spot/work lights x 4 , on roof (More for wider angle) doesn't need to be crazy wattage, haven't bought these yet, but lets call that another 24A total
Radio - Have replaced the factory one, but 4x50W MAX - so at half volume is this 8A?
Subwoofer - Just a compact powered one - 8.5A MAX
Fridge/Freeze - No idea yet on current draw, but think these are quite low, and will go via a split charge of some description into a leisure battery
I have factory A/C
And all the other factory stuff.

So, what do you reckon?

Thanks for your help - This auto electric stuff is a bit of a dark art to me.

john
 
LED lights draw far less than Incandescent/halogen e.g. 48 w LEDs pull 4a per light (8a total)
Even Chinese LEDs will have the power rating / current draw in the documentation
 
LED lights draw far less than Incandescent/halogen e.g. 48 w LEDs pull 4a per light (8a total)
Even Chinese LEDs will have the power rating / current draw in the documentation
These ones seriously don't have any useful info - Just BS ratings like lumens and Watts (But incandescent equiv - 3200W etc). And in the box are no specs. Really bad, and maybe shouldn't be allowed in the country, but eBay being eBay).
I have kind of worked out mine are about 270W, comparing them to others and they supplied a 30A fuse with the wiring harness.

https://www.ebay.co.uk/itm/7-inch-3...und-4x4-Spotlights-Black-12V-24V/323790433101
 

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