Alternator

Slownsy wrote:
Yes I intended to run a heavy cable to rear for charging FW, I know that the is a orange wire with 40A fuse from factory but as plugs and som of harness have been changed when right hand conversion was don. 6gage wire is often used for this here in Australia but wondering about fuse for use near alternator.
Frank

I would get a 20 amp DC/DC booster mounted near the trailer battery. Alternator will not even know.

https://www.renogy.com/12v-dc-to-dc-on-board-battery-charger/

Voltage on the trailer battery is the issue, not alternator amps.
This converter will put 14.7 volts and 20 amps right on the battery terminals.

As most people know, diesels take awhile to warm up and provide heat to the cabin.
Supplemental Heat provides heat to the cabin on start up and within a few minutes is providing 1000-1200 watts to the cabin. When the engines is warm enough to provide heat, supplemental heat automatically shuts down.

Chum lee wrote:
If your chassis battery is fully charged, expect the alternator output to be a fraction of it's maximum rated capacity until the existing loads drop the charge in the chassis battery.

Partially correct. The actual current (amps) output will be what ever is required to MAINTAIN the desired charging voltage. The point is, within a few minutes of starting the computer adjusts that voltage down to between 13.2V and 13.8V

Chum lee wrote:
Ford engineers designed their charging system that way to improve fuel mileage ...

Not just Ford. Every light and most medium duty vehicles. It has been that way for over 15 years.

Chum lee wrote:
... and to prevent people from doing what they want to do . . . . . charge the batteries in their camper with the chassis alternator.

Slownsy wrote:
Yes I intended to run a heavy cable to rear for charging FW, I know that the is a orange wire with 40A fuse from factory ...

You can still charge your house batteries, but it will require a DC-DC battery charger like from CTEK or Renology. And you won't need to use huge oversized wire to eliminate voltage drop !

Yes I intended to run a heavy cable to rear for charging FW, I know that the is a orange wire with 40A fuse from factory but as plugs and som of harness have been changed when right hand conversion was don. 6gage wire is often used for this here in Australia but wondering about fuse for use near alternator.
Frank

Does supplemental heat provide heat to the cabin or to the engine air intake for cold starting?

I have the 200 and 157 amp alternators in my DRW. If you have the optional supplemental heat, by default your truck will come with the heavy duty 200 amp. Supplemental heat draws 1000-1200 watts.
If it is a cold morning, the amperage draw is huge. Supplemental heat is on by default, no switch to turn it on or off unless you turn your heater completely off.
So on start up I have supplemental heat, all the seat heaters on, all the lights on including fog lights. The DRW has about 10 more lights than the SRW.Also, on cold mornings my air compressor usually turns on for a few minutes to fill the tank.There is also other stuff drawing amps, by my figures I am drawing over 200 amps.

To a certain extent, your chassis alternator output (voltage and current) is dependent on the current state of charge of your chassis battery(s) and the loads placed on the alternator by the VEHICLES electrical system. If your chassis battery is fully charged, expect the alternator output to be a fraction of it's maximum rated capacity until the existing loads drop the charge in the chassis battery. Ford engineers designed their charging system that way to improve fuel mileage and to prevent people from doing what they want to do . . . . . charge the batteries in their camper with the chassis alternator.

Chum lee

Slownsy wrote:
2015 6.7 Lariet do anybody know how many Amps the heavy duty alternator is, and how many Amps it can supply continues.
Frank

Plenty. Or do you have an extra ordinary demand for power?

Matt_Colie wrote:
Frank,

I just have to ask why you care?

If you are hoping to use it to recover the battery in a TT or other, this is usually a lost cause because of the required cable length and weight.

If you hope to use it to supply power when stationary, that is an all around bad idea for so many reasons.

Matt

Not to mention most of the power it produces goes to running the truck.

Frank,

I just have to ask why you care?

If you are hoping to use it to recover the battery in a TT or other, this is usually a lost cause because of the required cable length and weight.

If you hope to use it to supply power when stationary, that is an all around bad idea for so many reasons.

Matt