FWC Eagle - Cable capacity - DCDC charger upgrade

[markturnip]

Hello all!

Firstly apologies for starting another thread on this topic. I found a lot of other helpful threads related.

I'm the owner of a 2010 Eagle FWC which I've recently upgraded to 140AH LiFePO4 Lithium battery.

The previous setup simply used a battery guard connected to 2x3.6mm cables running to the truck bed cigarette socket, on the other end is the camper running to the 12v inlet.

I wish to replace this setup with a Victron Orion-Tr Smart 12/12-30A to properly charge my new lithium battery.

My concern is the current cabling is not sufficient and so I plan on rewiring the truck to a much more substantial cable with an Anderson plug.

I wonder if anyone knows what amperage the inlet cables FWC install are able to handle? or perhaps the wiring schematic? As I can't get visibility on where the cable on the inside of the camper runs.

I have a IOTA IDP-30 by the looks of it the inlet cable is connected straight to this via the isolator.

I had planned on installing the DCDC connector inside the truck before the cables running to the truck bed, however based on other thread perhaps the advice is it should be in the camper and as close to the lithium battery as possible.

Any advice much appreciated!!

 

[markturnip]

Seems that if I install DCDC charger in the truck, the other end would be supplying the entire camper including lights, fridge etc.

In which case it does seem to make sense to have it installed in the camper directly to the battery. Albeit lack of space!

But the question still remains - how much current can the 12V inlet take?

 

[jclifb]

I am finishing up my DCDC install today and am running all new 6awg wiring from the battery of the truck to the charger and bypassing any of the camper electrics. Your Iota is likely not suited to properly charge your new lithium battery to its fullest potential so you may want to look into swapping that out as well for a different unit.

 

[markturnip]

Thanks for response.

Since I'm so blind to what the cable is on the inside of the camper, I'm wondering if I need do the same.
Just like to do a tidy job of it! May have to drill a hole directly to the battery compartment from the outside.

My IOTA is just a Distribution Panel, not sure why I'd need to swap that out.
I've no plans to charge lithium battery from shore power/hookup/240v.

 

[Jon R]

Most FWC discussed here have an IOTA DLS-30 120vac to 12 vdc power converter/charger, so you mentioning an IDP-30 created confusion. There is no reason to replace that distribution panel.

 

[markturnip]

I've managed to remove some panels to reveal inlet terminal!

which is encouraging, as this means I can remove terminals and wire in a DCDC charger in place directly to the battery.

Still inconclusive of whether or not the DCDC charger is better in the truck or the camper!

 

[Jon R]

You definitely want the dc to dc charger to be close to the camper battery to minimize the voltage loss between the charger and the battery. The manual for the charger will say the same thing.

 

[markturnip]

Sure makes sense. Thanks!

The cable running to the truck bed is 2x3.2mm cables (running from earlier attached battery guard)

I think I'm just going to take the safer option and purchase a 20amp charger, until I have the time to upgrade this cable.

 

[Vic Harder]

The wire needs to be stripped to measure the size. That's likely 10AWG wire. It should say so on the outside jacket of the wire.

 

[Jack]

It's not a current issue. 10 AWG will easily handle 30 A. The Victron Orion Smart has an option to run a sense wire to the engine to detect engine on, which is great if you can figure out where to connect it on your particular engine and you add a sense line. When using the Orion "Smart" to detect engine on (no sense line), the voltage drop at the the DC-DC (assuming it is near your battery and about 25' of cable away from the alternator) is voltage drop. The 30 A surge on start up drops the voltage at the DC-DC to a level that tells the Orion that the engine is off, and the DC-DC shuts down. You can play with the Orion "Engine shutdown detection" and "Input voltage lockout" parameters and you may get the Orion to charge reliably with 10 AWG. With 6 AWG, the Orion usually behaves the way you want it too. In any case, For LiFePO4, (set as a battery preset) I recommend that you modify the "Battery settings" / "Absorption Voltage" to 14.5 V to more fully charge your battery.

 

[CreekRob]

IIRC 3.2mm x-section (minus insulation) would be about 8 gauge. I also think FWC used to use 10AWG wire in pre-lithium installs. 10AWG could do 30A, but you need to check the circuit protection too. I might want to go bigger, as Jack notes. Good opportunity to make sure everything is ship shape.

And put the DCDC in the camper. Doesn't it do BT? if that's so you're paying for that feature and odds are you'll be checking it in the camper anyway.

I don't know if you've settled on that Victron, but a benefit of the Kisae or Redarc DCDC units is that they incorporate a solar controller, which can be handy if you every want to incorporate solar.

 

[Edgewood]

I am replacing the 10 gauge wire between truck and Orion DC to DC charger. I installed a 30 amp fuse near the truck battery and another just before the charger in the camper. The new line is 6 gauge. Currently there is 8 gauge wire and 30 amp fuse between the Orion charger and house battery. Should I replace that with 6 gauge wire and another 30 amp fuse?

 

[Vic Harder]

I am replacing the 10 gauge wire between truck and Orion DC to DC charger. I installed a 30 amp fuse near the truck battery and another just before the charger in the camper. The new line is 6 gauge. Currently there is 8 gauge wire and 30 amp fuse between the Orion charger and house battery. Should I replace that with 6 gauge wire and another 30 amp fuse?

How long is that section of 6g between the Orion and the house battery?

 

[Edgewood]

Only a foot. I really appreciate your information Vic. It has really helped me take this project on.

8 gauge between house and Orion new 6 gauge between truck and Orion.

 

[Vic Harder]

a foot? no need to change the wire. No need for a fuse on that short section either.

You are most welcome.... keep asking questions!

 

[Jon R]

I am replacing the 10 gauge wire between truck and Orion DC to DC charger. I installed a 30 amp fuse near the truck battery and another just before the charger in the camper. The new line is 6 gauge. Currently there is 8 gauge wire and 30 amp fuse between the Orion charger and house battery. Should I replace that with 6 gauge wire and another 30 amp fuse?

The Orion 12/12-30 has an output of 30 amps, but it will draw 35 amps or so from the truck during bulk charging. You may find you need to increase the fuse size from the 30 amps you mentioned.

 

[Edgewood]

Thanks Jon. I actually used a Blue Sea System 7182 40 amp fuse that was mentioned earlier. I put another one just before the house battery. I was admiring my cable work today and noticed that I completly bypassed the fuse. GRRR.
I now just need to install a Anderson plug mount in the truck bed to accept the new Anderson plug.

 

[Vic Harder]

oh, and another reason to stick to 6g inside is that I believe the largest size cable that Victron gear will accept is 6awg.

 

[CougarCouple]

My electronics love big AWG.

Shocking I know.

,)

 

[Vic Harder]

My electronics love big AWG.

Shocking I know.

,)