DC - DC Charger Project

[howson]

Yoda ... maybe I haven't had enough coffee this morning, but for a Battle Born Absorption is 14.4v and Float 13.6V. From the Solar MPPT configuration:



For the actual switch setting, but I went through the same ???. For the 40A the settings are documented in my thread.

Howard

[ncitro]

Yoda I agree with Brian, I would go below not over unless they recommend otherwise. If you go over you will need to check your water more often as its likely to boil out.

[Country Campers]

I would recommend the 14.4 v for the float, it might be kinder to the battery. Hopefully Crown Battery will give you some info.

Brian

[Yoda]

Today I got out the Renogy 60A DC-DC charger and actually read the instructions. I found a place to mount and actually figured out I need to be careful otherwise I could put a screw through the bedroom floor

DIP settings - could use your your help.

Per Crown battery they provided the following information on Charging.
Voltage Setting
12V
Absorption/Bulk
14.5
Equalize
15.5
Float
13.5

However the DIP switched do not exactly line up
Choices
Absorption 14.4V, 14.1V, 14.7V
Float 13.8V. 13.5V. 13.2V

I am thinking of going with the 14.7 absorption and 13.5V float
I have also sent an email to Crown Battery.

Thoughts?
Keith

[Jlawles2]

Yoda Again Keith, the step drill and a slightly undersized hole on the terminal can be corrected if needed. If you look around a bit, sometimes you can find undersized holes on terminals. When all else fails, a piece of properly sized copper pipe, a good hammer or vise, some file work, and the step drill become friends to make a terminal.

[howson]

I hope I chose wisely?

The lug recommends a 1/4" stud. That equals 6.35mm according to a conversion website. Given the contemplated 6 mm stud on hand is used, that means there's .35mm of "slop" which is a whopping 0.01377953 inches. I'm not an engineer...but I'd guess the 6mm will work fine, though getting the recommended hardware is the safest approach.

I do like the specs on the lug you chose--should hold up well for the use intended.

To ease your mind set a reminder to do a follow-up inspection a month or so after installation (and a few actual uses). If there's an issue, it will be obvious due to discoloration or corrosion. I suspect it will be fine. (Even if you install a 1/4" stud I'd still suggest doing the follow-up inspection.)

[Yoda]

Yoda

Only .02 to add is make sure the connections are high quality, pure copper and the diameter of the lug must match the stud installed on the battery snugly. Too much "slop" and there's a real possibility of resistance at the connection. Resistance = power loss and heat build up (obviously not a good thing). When running there will be up to 60+ amps running through the wires to/from the truck's battery.

No doubt you remember my problem was opposite of yours--I had to install a lug on the negative side of the battery terminal (passenger side). I've had it off a few times to inspect for heat damage or corrosion build-up. So far everything looks good so I don't have any concerns other than the standard BE CAREFUL when working around those batteries!

And yes, I know all about whacking my noggin on anything within arm's reach.

Howard
Theses are the terminals I am using https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1

Now I just checked the fit on my 6mm bolt I was thinking of using as a stud. There is a slight amount of slop - same with the fit on the Ford aux post. It's easy to slip on. The site description says its the proper size "This particular variant has a 1/4" Eyelet suitable for use with 2 AWG (2 Gauge) 35 sq. mm Cable & 1/4" (M6) " The 5/16 I got for the solenoid have a little less slop , but still slip on easily.

I hope I chose wisely?

Keith

[Cate&Rob]

I am going to drill and tap this terminal for the new 6mm positive post. This is on the drivers side. I am thinking of doing it on the battery
Am I nuts for thinking this?

I would not try to drill and tap that terminal while it is on the battery. A slip of the drill and you have bigger problems. Also, that terminal is too thin to tap with sufficient threads to secure the connection and the tap will have to go through farther than the distance to the top of the battery to cut full threads. Better to remove the terminal, drill it in a safer location and install a bolt from the bottom and nut on the top for a secure connection before reattaching to the battery (in my opinion).

Rob

[Hogdrv]

Those are the cables I followed to the back, worked great and you can see in my picture where I ran the upfitter wire. Sounds good to me!
The drilling by the battery does scare me though and yes BE CAREFUL!!!!!
Jim

[howson]

Yoda

Only .02 to add is make sure the connections are high quality, pure copper and the diameter of the lug must match the stud installed on the battery snugly. Too much "slop" and there's a real possibility of resistance at the connection. Resistance = power loss and heat build up (obviously not a good thing). When running there will be up to 60+ amps running through the wires to/from the truck's battery.

No doubt you remember my problem was opposite of yours--I had to install a lug on the negative side of the battery terminal (passenger side). I've had it off a few times to inspect for heat damage or corrosion build-up. So far everything looks good so I don't have any concerns other than the standard BE CAREFUL when working around those batteries!

And yes, I know all about whacking my noggin on anything within arm's reach.

[Yoda]

howson ncitro Cate&Rob Hogdrv WondersAwait Jlawles2 did I forget anyone?

So after looking at this and finding the bracket to mount the solenoid has easy access I am still going to add a power stud to the drivers side positive battery terminal and run power from there. Ford cables appear to be #2 so the feed across in the stock wiring to the second battery should not be an issue. Whats nice is the main cable loom with Fords wiring runs down the drivers side so plenty of good places to tie up the #2 bundle of feed lines to the bed.

So advice please - am I looking at this correctly? Drivers side will be much cleaner and I will only need to run one small wire across the back from the up fitter switch box.

Thoughts?

Thanks Keith

[Hogdrv]

I brought the cables down the driver’s side because of the exhaust and I had a place to mount the solenoid, passenger side too busy no room for it.

Jim

[Cate&Rob]

Maybe that is why there is no post on the drivers side as that is the aux battery, not the primary.

Hi Keith,

You may be on to something with this theory . . . there has to be a reason (other than saving 2 cents) that Ford would not put an aux attachment post on the driver's side battery. Tagging howson Howard on this since I know that he came off the passenger side battery and brought the cables down that side of the truck.

Rob

[Yoda]

Now lets trace the drivers side battery cable path.

The positive and negative enter a loom and are directed downward in a plastic housing.


Down towards the engine the positive wire goes left behind the drivers side alternator and crosses over as best as I can tell. This appear to be #2 battery cable and is the sam size as what I fond on the passenger side battery.

[Yoda]

Ok here we go. First Caution! when crawling under the truck watch your head.

I know think I have this figured out.

First is what I will call the positive combiner box.
This box is on the passenger side right next to the battery. The second battery cable on the left comes from the drivers side from what I can figure. While I got the cover loos it cant be removed without disconnecting the cable from the battery. It also appears the power feed from the alternators comes into the bottom of the box too.
Te left smaller purple wire runs over to the alternators. I have two on the truck. I am not sure where the center red wire goes - possibly to the starter. At the bottom left you can see the cable from the passenger side battery and hidden behind left the cable from driver side battery.

As you can see the alternator power appear to be the cable labeled AE.