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How much "extra" power does the alternator supply?

entoptics

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Google suggests there's a 250A alternator in the RR. All well and good, but I just can't seem to find the "nominal" needs for the truck...

I'd like to know how much headroom I have for auxiliary electrical needs plus recharging the battery when I'm already "maxed out" with normal truck stuff (e.g. stereo, AC, headlights, charging a couple devices with the USB ports, etc).

250A - (My Needs) - (Truck Needs) = charging current....

I can easily calculate the auxiliary draw I'm adding with my accessories, but I don't know what the truck needs, so I can't really solve the above equation for the leftover current for charging the onboard battery...

If I can get a rough estimate of the truck's baseline needs, then when I'm out on an adventure, and drain some of the battery while the truck isn't running, I'll have a better estimate of how much driving I would need to do to keep the state of charge neutral to positive.

Anyone have a handle on the (Truck Needs) part of the equation?
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Aemonn

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Google suggests there's a 250A alternator in the RR. All well and good, but I just can't seem to find the "nominal" needs for the truck...

I'd like to know how much headroom I have for auxiliary electrical needs plus recharging the battery when I'm already "maxed out" with normal truck stuff (e.g. stereo, AC, headlights, charging a couple devices with the USB ports, etc).

250A - (My Needs) - (Truck Needs) = charging current....

I can easily calculate the auxiliary draw I'm adding with my accessories, but I don't know what the truck needs, so I can't really solve the above equation for the leftover current for charging the onboard battery...

If I can get a rough estimate of the truck's baseline needs, then when I'm out on an adventure, and drain some of the battery while the truck isn't running, I'll have a better estimate of how much driving I would need to do to keep the state of charge neutral to positive.

Anyone have a handle on the (Truck Needs) part of the equation?
Pretty sure google confuses the ranger raptor with the f150 raptor. I believe the RR has a 170 amp alternator. I looked it up a while ago. I'll see if I can find the link.

As for the trucks needs, that is variable. I want to say you have about 30% of that 170 amps to safely play with.
 

stuartmunto

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Pretty sure google confuses the ranger raptor with the f150 raptor. I believe the RR has a 170 amp alternator. I looked it up a while ago. I'll see if I can find the link.

As for the trucks needs, that is variable. I want to say you have about 30% of that 170 amps to safely play with.
The RR alternator provides 110amps at idle (625rpm) and then increases to 250amps at 2,500rpm and above. It's all detailed in chapter 4 of the body manual (pg 103-105):

https://www.ford.com.au/content/dam/Ford/website-assets/ap/au/owner/vehicle-support/body-equipment-manuals/2021 Ranger V6 BEMM_Final.pdf

The 170amp alternator might be for the 2.3lt engine. I would expect the 2.7lt to be the same as the 3.0lt
 

Aemonn

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It was 150 on car and driver, not sure why 170 was stuck in my head. Was the only place I could find it back when I was looking.

That document looks like it's targeted for the AUS market. We don't get a turbo diesel here, and ford sure likes to dial things back for the US market (no rear ac vents, etc).

I found the replacement part but no specs listed.
https://parts.ford.com/shop/en/us/electrical/starters-and-alternators/alternator-30l-p-gl9928?pdp=y

I'll happily go along with 250, but I'll be even happier if I can find documentation from the US market.
 

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RLE55

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Google suggests there's a 250A alternator in the RR. All well and good, but I just can't seem to find the "nominal" needs for the truck...

I'd like to know how much headroom I have for auxiliary electrical needs plus recharging the battery when I'm already "maxed out" with normal truck stuff (e.g. stereo, AC, headlights, charging a couple devices with the USB ports, etc).

250A - (My Needs) - (Truck Needs) = charging current....

I can easily calculate the auxiliary draw I'm adding with my accessories, but I don't know what the truck needs, so I can't really solve the above equation for the leftover current for charging the onboard battery...

If I can get a rough estimate of the truck's baseline needs, then when I'm out on an adventure, and drain some of the battery while the truck isn't running, I'll have a better estimate of how much driving I would need to do to keep the state of charge neutral to positive.

Anyone have a handle on the (Truck Needs) part of the equation?
Some good info here if you determine My needs exceed the Truck needs.
https://js-alternators.com/blogs/bl...UdmsIwU2AGKdfVWrrPo5Q-cyW5j8sr42I9vuGnSq6nish
 

Bushmechanic

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purdyd

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There is a disclaimer in the manual on the inverter saying that in park it puts out 400W but in drive is could be less.

So I'm guessing that you have less than 33 amps at 12 volts in drive as "excess" power from the alternator.
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