wiring from Alternator

[XERTYX]

Yup. Objective and optimistic while being objectively optimistic and also realistic at the same time. The man will tell you it CAN be done. But has a roadmap of failure that you can learn from or add your failures to.

I'd ask my alternator questions of this guy. . .
Thats objective. But my objective is that I know JACK about charging from my engine... except my amateur radio basics. Pro tip- for your amateur radio license test a car alternator is a way to recharge a 12v system. That's a real question on the test BTW.

 

[LIFE]

@Scott3569, I hear and feel your goal. As I see it, using your current, supposed 160-amp alternator, the project will never truly be completed. The concept will work, but you will most always be running at a power deficit --due to insufficient amperage output (from the 160-amp alternator), to satisfy the OEM circuits, as well as your secondary/accessories; think inclemate weather with 95% of *everything running.

So, using the stock OEM alternator will work, up to a certain point. As it is now, your existing and any future alternator along with its internal regulator (rated at 160-amps), will not be efficient or even live long.

NOTE-01: Some vehicle manufactures have the vehicles computer monitor the charging circuit or voltage. Additional batteries, even one, connected in parallel to the OEM starting battery, may inform the computer, that the vehicles battery indeed is sufficiently charged, and may-not allow the alternator circuit to charge other batteries in need.

First, now that I see a little more about your load (amperage usage), and barring everything else:

1) Disconnect the existing charging cable from the alternators output lug; don't let it ground-out.
2) get a length of 3/0 cable --I personally use 4/0, running from the alternator output lug. The first stop is a fuse-block and fuse rated based on your total load; I.E. your total intended amperage draw/usage <-- this includes the OEM circuits and your 'house/secondary' circuit.

3) On the out-terminal of your fuse is where your obvious load connects. Yes, your battery, the cable I suggested that you not let it ground-out, is part of the load; reconnect it here. When you are ready with your secondary/accessory/house circuit, whether it be through an isolator, relay or some other method, connect that load here as well. This is 'my' reason for asking your application and the circuits intended load.

**We must get an approximate 'combined' number for your current/amperage usage.
; more on this later. Currently, I'm attempting to get your source\primary wiring for your accessories acceptable to endure for the 'couple of years' you stated in the video. Then when you
you acquire the next vehicle, you most likely will be able to continue to use this same cable; give or take some length.

I'll stop here --not to go to fast/far and, wait for questions from you or feedback from other members.

your turn ...

 

[abnorm]

Welcome to the forum LIFE........the OP is in a Dodge Caravan minivan and wants to recharge a couple 100 AH AGM batteries...........

.........Rewire 4/0 to the stock alternator ?...........How/Why?

 

[Scott3569]

@Scott3569, I hear and feel your goal. As I see it, using your current, supposed 160-amp alternator, the project will never truly be completed. The concept will work, but you will most always be running at a power deficit --due to insufficient amperage output (from the 160-amp alternator), to satisfy the OEM circuits, as well as your secondary/accessories; think inclemate weather with 95% of *everything running.

So, using the stock OEM alternator will work, up to a certain point. As it is now, your existing and any future alternator along with its internal regulator (rated at 160-amps), will not be efficient or even live long.

NOTE-01: Some vehicle manufactures have the vehicles computer monitor the charging circuit or voltage. Additional batteries, even one, connected in parallel to the OEM starting battery, may inform the computer, that the vehicles battery indeed is sufficiently charged, and may-not allow the alternator circuit to charge other batteries in need.

First, now that I see a little more about your load (amperage usage), and barring everything else:

1) Disconnect the existing charging cable from the alternators output lug; don't let it ground-out.
2) get a length of 3/0 cable --I personally use 4/0, running from the alternator output lug. The first stop is a fuse-block and fuse rated based on your total load; I.E. your total intended amperage draw/usage <-- this includes the OEM circuits and your 'house/secondary' circuit.

3) On the out-terminal of your fuse is where your obvious load connects. Yes, your battery, the cable I suggested that you not let it ground-out, is part of the load; reconnect it here. When you are ready with your secondary/accessory/house circuit, whether it be through an isolator, relay or some other method, connect that load here as well. This is 'my' reason for asking your application and the circuits intended load.

**We must get an approximate 'combined' number for your current/amperage usage.
; more on this later. Currently, I'm attempting to get your source\primary wiring for your accessories acceptable to endure for the 'couple of years' you stated in the video. Then when you
you acquire the next vehicle, you most likely will be able to continue to use this same cable; give or take some length.

I'll stop here --not to go to fast/far and, wait for questions from you or feedback from other members.

your turn ...

@Life


Ok So if I am understanding you correctly.. the ALT I currently have will not supply enough charge to charge a second battery
(keep in mind, My alternator will not be my only charging source, I do plant to add at least 1 Solar panel. Most likely 2, from what I have learned in other posts I have put up)..

If my ALT will not put out enough charge (taking out the possible computer issue). 

then this conversation is dead where we are at.. I have seen that there is an ATL on the after market for a 240amp (if my memory serves correctly)

I do understand that if I connect a wire to the output bolt of the alternator that I can not allow this to ground out.. and I would be extremely careful not to do so.. 

now, I just found this from Renogy
  https://www.renogy.com/dcc30s-12v-30a-dual-input-dc-dc-on-board-battery-charger-with-mppt/

I am on the fence with an all in one unit for the same reason someone else Mentioned.. 8 times out of 10-I would not buy an all in one unit.. 
However, this seems to make things much more simplistic. And I do believe this is one of the times I would get an all in one.

So my understand is the wiring sequence Using the above Dc-Dc charger is as follows

+Starter Battery------Fuse---charger----House BAT----Accessory Fusebox

with negative going to the chassis of the vehicle or from the Negative side of the Starter battery.. 

Am I keeping up Professor? 

 

[LIFE]

@abnorm, I suggested for the op to use 3/0. 'I' use 4/0 for my rigs/application. Additionally, the op 'initially' had neglected to mention some details. Unless I missed something, the op has not mentioned whether the fridge was ac/vdc, nor have I read what his total approximate application load combined with the total vehicle is.

Using/installing 3/0 on his primary/feeder, I. E. from Alternator output >> fuse-block, sized for the load, should handle his needs for:

a) the duration of this vehicles ownership; he stated 02-years. After which he can transplant to the next vehicle.
b) the upgrade to an alternator with sufficient output; his existing, supposed 160-amp alternator is going to disappoint him.

I have a notion that the op has not posted all of his intended load. My suggestion(s) to date. allows room for growth, without doing things over-and-over.

What did I miss?

 

[user 423]

^
His other thread...

 

[user 37446]

Wow, there's some serious overkill happening here, reminds me of towing threads on rv forums where it takes a 1 ton dually to pull a single axle rv for some folks to be "happy"...

You've got a Caravan with maybe a 160 amp stock (old) alternator that factory bench tested in some lab once upon a time at 160 amps when at a perfect 70 degrees blah blah.
Real world other than a direct short you'll not likely see more than 100 amps from that alternator and that only for a few minutes at best. Now subtract the requirements of the van and you get what's left over for your house battery.

So let's humor the "overkill" group and say your alternator is magic and can output a steady 95 amps all day long in addition to the van loads (fantasyland). Looking at the table from the folks at west marine, (who know just a smidgen about marine parts and needs), you'll see that at 15' a 2 AWG stranded copper (not CCA) wire is fine.
See extract from their chart below:

https://www.westmarine.com/WestAdvisor/Marine-Wire-Size-And-Ampacity
3% Voltage Drop
Use 3% voltage drop for critical applications affecting the safety of your boat and crew, such as running lights, blowers, electronics and panel board feeds. Remember that the Length is a round-trip distance. This table is for 12-Volt systems only.

Current (Amps) →
Length ↓ 5A 10A 15A 20A 25A 30A 40A 50A 60A 70A 80A 90A 100A
10' (3m) 18 14 12 10 10 8 6 6 6 6 6 4 4
15' (5m) 16 12 10 10 8 8 6 6 4 4 4 2 2

So AWG 2, while likely overkill, is fine for you. Add a 100 amp fuse and if you want, a simple on/off switch to your AGM and you will be ok.

Or, install 3/0 wire at over $4 a foot and nearly .5 inch thickness, which will result in difficult crimping connections and you are ready for the alternator from hell upgrade in the future.

Or follow what HDR says about wiring and read up on the forum electrical section for awhile.

 

[Scott3569]

Yup. Objective and optimistic while being objectively optimistic and also realistic at the same time. The man will tell you it CAN be done. But has a roadmap of failure that you can learn from or add your failures to.

I'd ask my alternator questions of this guy. . .
Thats objective. But my objective is that I know JACK about charging from my engine... except my amateur radio basics. Pro tip- for your amateur radio license test a car alternator is a way to recharge a 12v system. That's a real question on the test BTW.

Really hope things are going well for you, I have always considered getting my ham radio License, just never did it.. maybe after I relax a little after my build..

 

[PlethoraOfGuns]

I think everyone is overthinking all this. What do the manufacturers say? A good quality battery to battery charger should only delivery power to the aux battery if there is sufficient power available. If the stock alternator is being strained by things like lights, cab heater, charging starter battery, etc voltage will drop and the aux battery will get less charge or none at all until the alternator has caught up. I know that's how the battery to battery chargers work, not 100% sure about isolators. Can someone else confirm my suspicions about isolators? Maybe there are quality ones that can limit power to aux battery based on available alternator power?

Now adding one of these devices, might require some wiring upgrades. Most people dismiss the important grounds between engine/chassis and body/chassis. Don't be that guy!

 

[Scott3569]

Well now I am just all kinds of confused.. it's automotive and standard electrical work, Never would have realized there are so many different way to do what should be a fairly simple Job and a Family Minivan..

All I want to do, is charge a house battery or two, So I have have a few led lights, a 12v tv, charge my phone, run my computer, 12v fridge, charge ryobi batteries and have some extra to play with..

I really did not think it was going to be all that difficult..

I appreciate all the input, But my brain is fried

 

[bullfrog]

It isn't really. I just ran a good set of jumper cables to my house batteries from my vehicle battery. I disconnected the cable when I parked and carried a charged up jumper pack in case I forgot to disconnect when I parked. All my camping,tool batteries and ect. were run off the house batteries. After a couple years I ended up replacing the batteries as I had abused them by letting them discharge more than I should and never getting them fully charged. I'm pretty sure my alternator had some extreme use as well but everything worked for about two years just fine. All the information above is just trying to improve the system. Bottom line is you need to fully charge all your batteries daily if you expect them to last and unless you are driving all day long it ain't gonna happen and you will eventually have to replace the batteries unless you use a generator or solar for daily charging. I didn't have a frig and used Ryobi lights and fans so basically charged phones, Ryobi batteries, inflators and such. The first year I carried a small generator but never used it much as it was noisy. Now I use a larger generator and solar as I got tired of buying batteries but the original method worked fine for the first two years at a cost of a couple batteries.

 

[LIFE]

^
His other thread...

@abnorm, I sure did miss that thread, which probably posted while I was drafting. Thanks for that.

 

[LIFE]

Wow, there's some serious overkill happening here, reminds me of towing threads on rv forums where it takes a 1 ton dually to pull a single axle rv for some folks to be "happy"...

The overkill coming from my postings is/are due to the op not providing enough data about his intended application. As I have posted/stated previously, within this thread, asking the op for an approximate total application load. Additionally, the op has amended at least two items, on two separate occasions, from solenoid to isolator. Then from " house batteries" to his recent post of

" the ALT I currently have will not supply enough charge to charge a second battery"

... which somewhat changed the configuration of his 'worded' install. Which is it batteries or battery?

Once again, since my last two replies, the op added another device to the mix --Dc-to-dc charger--, that was not initially mentioned; neither in this thread or his youtube video. Rather than not assist or, provide data that would have the op doing this again, I provided the information that *I know* will work in any vehicle and allow the installer to upgrade with addition devices/amps to the limit of the installed fuse-block and fuse. I've been using a larger scale of the suggested cable, going on three years and counting, for a commercial application.

I do remember posting or alluding to 'me', stopping and waiting for feedback/questions from the op and others. The feedback, I was hoping would include something resembling *at least* the op's approximate application load.

I'm listening and watching.

 

[user 37446]

To whomever it may concern:

IMHO, to safely charge an AGM battery (or even two!) which are lead acid and follow typical lead acid charge profiles, you need an adequately sized automotive stranded copper wire, grounded back to the block (not the van body), fuzing to protect said wire rating and finally, proper crimping.
Now whether an older alternator will ever get two 100 amp deep cell AGM's fully charged is, well, rather optimistic thinking.

If the OP checks published AWG wiring charts he can ascertain the recommended wire sizes. To undersize will produce resistance/slow charging/heat and to significantly oversize merely wastes $$.

It should be noted that many Chrysler/Dodge vans had 10 gauge fusible links in their alternator to battery wiring from the factory so a 2 or even a 4 gauge (horrors) AWG stranded copper wire should suffice for what he is hoping/intending to do.

If the OP so chooses, he could do a search under the heading "big 3 wiring upgrade" and see what the audiophiles do to upgrade their stock vehicle electrical systems. A link for such an article is here: https://www.crutchfield.com/S-KJqGgZPwKVP/learn/big-3-alternator.html

A quotation from that same article says:
The Big Three wiring upgrade
"A good, cost-effective improvement is to perform the "Big Three" electrical upgrade. This will vastly improve your vehicle's electrical system, allowing more current to flow easier to all components. This upgrade replaces or augments three key cables in the electrical system with 1/0 or 4 gauge wires: the battery ground to chassis wire, the chassis to engine block wire, and the alternator plus to battery plus wire. This increases your electrical system's current flow capability, ensuring a more consistent voltage under varying demand conditions.

An unfortunate possible side effect of doing the Big Three is that occasionally it only makes your lights dim even worse. This happens because the amplifier is now able to suck juice better from the system through the bigger straw (the new cables). " (End of copied portion)

The OP admits that automotive electricals is not his strong suit, (the same with most people). A little research on the web will show him factual, proven information as opposed to forum chatter.

Thanks to ALL of you who are attempting to steer him in the right direction. Like in all things, there is a spectrum of possible ways to do it from cheap to costly. I am merely advocating "good enough", the same on the towing with a car thread... (Oops, may have done some "she-it disturbing" with that one...)

 

[LIFE]

@Life


Ok So if I am understanding you correctly.. the ALT I currently have will not supply enough charge to charge a second battery (keep in mind, My alternator will not be my only charging source, I do plant to add at least 1 Solar panel. Most likely

@Scott3569
That is not what I'm suggesting. The following is what I was 'initially' addressing:
--charge more than one --unknown batteries. In this very post, that I'm replying (above), you now say a second 'battery'.
-- Initially you said a solenoid; later amended to an isolator. For the most part isolators have voltage drops, unless you use schottky diodes; less voltage consumption.

-- I never saw you post anything about a secondary charging solution, the solar panel, until I read this post.

You keep slowly, amending things before you have addressed the basics --> what is the applications' approximate total working load? This does not include any start-up surge.

THE EXISTING alternator: for whatever life it has left, and if you were to replace it with any other 160-amp unit, your entire OEM circuits with the added house application will more the likely be running at a deficit, and you'll probably be replacing alternators prematurely. <-- This was my thought before I found out (read), your intention to add a solar panel.

2, from what I have learned in other posts I have put up)..

If my ALT will not put out enough charge (taking out the possible computer issue). 

then this conversation is dead where we are at.. I have seen that there is an ATL on the after market for a 240amp (if my memory serves correctly)

Am I keeping up Professor? 

This conversation/discussion is not dead, you are learning from others. Circling back to one of the primary concerns/questions, what is the approximate application load? Now that I know your looking into solar, if your applications total load can be satisfied with one/two batteries, find a solar solution for the house circuit and call it a day. No matter how you slice this, you may want to figure the house applications total load.

The vehicle OEM didn't really care much about powering anything but their product. What else have I missed while drafting/proof reading this?

 

[Scott3569]

@Scott3569
That is not what I'm suggesting. The following is what I was  'initially' addressing:
--charge more than one --unknown batteries. In this very post, that I'm replying (above), you now say a second 'battery'.
-- Initially you said a solenoid; later amended to an isolator. For the most part isolators have voltage drops, unless you use schottky diodes; less voltage consumption.

-- I never saw you post anything about a secondary charging solution, the solar panel, until I read this post.

You keep slowly, amending things before you have addressed the basics --> what is the applications' approximate total working load? This does not include any start-up surge.

THE EXISTING alternator: for whatever life it has left, and if you were to replace it with any other 160-amp unit, your entire OEM circuits with the added house application will more the likely be running at a deficit, and you'll probably be replacing alternators prematurely. <-- This was my thought before I found out (read), your intention to add a solar panel.



This conversation/discussion is not dead, you are learning from others. Circling back to one of the primary concerns/questions, what is the approximate application load? Now that I know your looking into solar, if your applications total load can be satisfied with one/two batteries, find a solar solution for the house circuit and call it a day. No matter how you slice this, you may want to figure the house applications total load.

The vehicle OEM didn't really care much about powering anything but their product. What else have I missed while drafting/proof reading this?

I answered your question the first time the best I am able.. I am thinking that if I was able to give you the information you are looking for.. there probably would not be a need for this post.. 

I will run LED lights
I have a cell phone, Computer, I will be getting an alpicool cl20, eventually probably a 12v small t.v.. and I want some extra room in my system in case.. 

MY alternator is virtually new, less than 1000 miles on it.. 

I don't know what else to tell you.. 
I am really trying to understand what people are telling me, But with all the different opinions and not much information in some of the responses , I am becoming even more confused from when I posted the question.. 

Once again this subject has escaped me in my life.. So I am trying to learn on the fly.. 


**I appreciate the responses from you and everyone else****

But I think for the moment I need to leave this subject.. Because I am not learning a thing

 

[LIFE]

@Scott3569, apologies from me. Perhaps I wasn't clear. When I requested the amperage or work load, I am meaning the total (combined) amperage; the numbers. An example can be found here -->

https://www.lilacresort.com/appliance-amperage-draw-chart/

Review that, match the chart as best you can to the devices you plan to use, -or-, do the math for each of your devices.

THE MATH:
To obtain Amps you need both Watts and Volts:
The formula is (W)/(V) =(A). For example, if you have a power of 10W running at 5V, the current is 10W / 5V = 2A.

Using either of those methods, continue by adding the sub-total for each, which should result in an approximate work-load (amperage use), for that house circuit. Now you have something to build on. You can informatively: size wire, choose an economical and hopefully, efficient method of maintaining your power source without burning a hole in your pocket.

If you can satisfy your house circuit with solar 'charging' alone, go for it. Less moving parts, less fuel burned etc.

Your thoughts?

 

[Scott3569]

@Scott3569, apologies from me. Perhaps I wasn't clear. When I requested the amperage or work load, I am meaning the total (combined) amperage; the numbers.  An example can be found here -->

https://www.lilacresort.com/appliance-amperage-draw-chart/

Review that, match the chart as best you can to the devices you plan to use, -or-, do the math for each of your devices.

THE MATH:
To obtain Amps you need both Watts and Volts:
The formula is (W)/(V) =(A). For example, if you have a power of 10W running at 5V, the current is 10W / 5V = 2A.

Using either of those methods, continue by adding the sub-total for each, which should result in an approximate work-load (amperage use), for that house circuit. Now you have something to build on. You can informatively: size wire, choose an economical and hopefully, efficient method of maintaining your power source without burning a hole in your pocket.

If you can satisfy your house circuit with solar 'charging' alone, go for it. Less moving parts, less fuel burned etc.

Your thoughts?

Are you seriously suggesting to someone that is going to live in this type of situation full time, to only rely on one charging system.. 
If I was able to delete this thread I would. But I do not see an option for it..

 

[Matlock]

Wow, so many replies and so little clarity for a new guy trying to get a grasp of all this. Reminds me of the help "John something" used to give.

Anyway, to the OP.
Call Renogy on the phone and ask about all the requirements needed for the $224 dollar DC-DC unit you linked to.
From wire size and connectors and how and where with what. THEY will give you exactly what you need and answer all your questions.
You already have enough info at hand and if you look at the wiring diagram in that link it's going to be easy talking to their tech. They've been around a few years and are used to working with "new to DC electric" folks.
That 224 dollar unit is not expensive for what it does and worth it for many reasons.

PS be sure to ask what the limitations are of this system. Worth knowing.

just my ol 2¢

 

[highdesertranger]

We are just confusing Scott. So much so that he asked for this thread to be Deleted. For the time being I am going to close it until I from him directly.

Highdesertranger