|
|
07-15-2024, 03:22 PM
|
#21
|
Bronze Member
Join Date: Jul 2024
Location: Colorado
Posts: 28
|
Avanti.... great explanation! This is definitely a viable option!
I guess I need to check my alternator output amperage, as well as find a wiring diagram for the Pleasure-Way so I know where the house side of the current battery isolator goes.
I'm guessing a DC to DC charger somewhere in the house feed off the current battery isolator could regulate the charge properly as well. Cost wise about the same. I guess I'm try to find the least intrusive way to allow my alternator to charge to separate batteries with different charging profiles.
Still researching and asking questions but maybe there is light at the end of the tunnel!
Thank you!
|
|
|
07-15-2024, 05:55 PM
|
#22
|
Platinum Member
Join Date: Dec 2016
Location: America's Seaplane City, FL
Posts: 1,000
|
Quote:
Originally Posted by Nobadays
Avanti.... great explanation! This is definitely a viable option!
I guess I need to check my alternator output amperage, as well as find a wiring diagram for the Pleasure-Way so I know where the house side of the current battery isolator goes.
I'm guessing a DC to DC charger somewhere in the house feed off the current battery isolator could regulate the charge properly as well. Cost wise about the same. I guess I'm try to find the least intrusive way to allow my alternator to charge to separate batteries with different charging profiles.
Still researching and asking questions but maybe there is light at the end of the tunnel!
Thank you!
|
Using a dc/dc charger eliminates the need for the battery isolator. I'm using a 40 amp Li Time dc/dc charger. It does have a switch for different battery types. I'm not a fan of the 14.6 max for lithium but it is quick to shut down once reached, a good thing. Also, when idling or putting around in city traffic the dc charger is still pulling upwards of 50 amps. My volt meter is down around 10 amps at idle after a bit. To alleviate these concerns I simply mounted a switch on the dash to control the signal/ignition wire leading to the charger. In essence the charger is manually controlled. Do hook up to an ignition on wire.
The alternator is whatever Chevy used in '97, 134(??) amp.
Avanti's method also sounds deliciously elegant and simple.
__________________
Tick tock, baby(Ironbuttal)
2000 Roadtrek Chevy 200 Versatile(sold)
'98 Safari Trek 2480
Just for fun:'15 Kawasaki Versys650LT
Perfection is a fantasy, though improvement is possible(Wifey).
|
|
|
07-15-2024, 06:18 PM
|
#23
|
Bronze Member
Join Date: Jul 2024
Location: Colorado
Posts: 28
|
Quote:
Originally Posted by SteveJ
Using a dc/dc charger eliminates the need for the battery isolator. I'm using a 40 amp Li Time dc/dc charger. It does have a switch for different battery types. I'm not a fan of the 14.6 max for lithium but it is quick to shut down once reached, a good thing. Also, when idling or putting around in city traffic the dc charger is still pulling upwards of 50 amps. My volt meter is down around 10 amps at idle after a bit. To alleviate these concerns I simply mounted a switch on the dash to control the signal/ignition wire leading to the charger. In essence the charger is manually controlled. Do hook up to an ignition on wire.
The alternator is whatever Chevy used in '97, 134(??) amp.
Avanti's method also sounds deliciously elegant and simple.
|
I'm kind of heading that direction. A DC to DC charger would be a somewhat simple solution I think. I would likely use Victron as their equipment is very controllable allowing me to set the lifepo4 parameters accurately.
My big unknown for going that direction is how/where exactly the house side of the current battery insulator goes. If it is direct to the battery ( which I suspect as it is 2/0 cable) then it might be quite simple to remove theinsulator, reattach the alternator output to the chassis battery. Connect the house lead to the DC/DC charger output then the input back to the chassis battery. I would probably use a bus bar for those connections and appropriately sized fuse blocks.
I've got a query in to the Pleasure-Way forum as well. Somebody on there must have done this already!
It's getting clearer! Thanks!
|
|
|
07-15-2024, 06:47 PM
|
#24
|
Platinum Member
Join Date: Aug 2010
Location: Minnesota
Posts: 12,456
|
Quote:
Originally Posted by Nobadays
I'm kind of heading that direction. A DC to DC charger would be a somewhat simple solution I think. I would likely use Victron as their equipment is very controllable allowing me to set the lifepo4 parameters accurately.
My big unknown for going that direction is how/where exactly the house side of the current battery insulator goes. If it is direct to the battery ( which I suspect as it is 2/0 cable) then it might be quite simple to remove theinsulator, reattach the alternator output to the chassis battery. Connect the house lead to the DC/DC charger output then the input back to the chassis battery. I would probably use a bus bar for those connections and appropriately sized fuse blocks.
I've got a query in to the Pleasure-Way forum as well. Somebody on there must have done this already!
It's getting clearer! Thanks!
|
If you have a 2/0 cable to the coach in a 200ah of lead acid van with a stock alternator, it is not going to be original, I think. We usually see #6 or #4 wire for 50 or 80 amps to the coach in those situations. It could be it was run to an inverter somewhere so the microwave or other device could be used with the engine running. We have seen a few done that way.
It should be really visible wherever it goes as that is a big cable.
|
|
|
07-15-2024, 06:57 PM
|
#25
|
Bronze Member
Join Date: Jul 2024
Location: Colorado
Posts: 28
|
Quote:
Originally Posted by booster
If you have a 2/0 cable to the coach in a 200ah of lead acid van with a stock alternator, it is not going to be original, I think. We usually see #6 or #4 wire for 50 or 80 amps to the coach in those situations. It could be it was run to an inverter somewhere so the microwave or other device could be used with the engine running. We have seen a few done that way.
It should be really visible wherever it goes as that is a big cable.
|
Pretty certain it is 2/0, certainly not #4 or #6awg. This thing is bone stock, no inverter to run appliances. We must either be on shore power or generator to use the 120v appliances.
Yep, I guess I'm going to have to crawl under the length of the van and see if I can trace that wire.
I did just hear from someone on the Pleasure-Way owners group who placed a DC to DC charger on the house side of his current battery isolator. I think I understand you to say if I used one of these I could eliminate the isolator.
Thank you!
|
|
|
07-15-2024, 07:07 PM
|
#26
|
Platinum Member
Join Date: Aug 2010
Location: Minnesota
Posts: 12,456
|
Quote:
Originally Posted by Nobadays
Pretty certain it is 2/0, certainly not #4 or #6awg. This thing is bone stock, no inverter to run appliances. We must either be on shore power or generator to use the 120v appliances.
Yep, I guess I'm going to have to crawl under the length of the van and see if I can trace that wire.
I did just hear from someone on the Pleasure-Way owners group who placed a DC to DC charger on the house side of his current battery isolator. I think I understand you to say if I used one of these I could eliminate the isolator.
Thank you!
|
People have done the B to B after the isolator, but all you have is a voltage drop and lost energy to the B to B with no real benefits.
|
|
|
07-15-2024, 07:22 PM
|
#27
|
Bronze Member
Join Date: Jul 2024
Location: Colorado
Posts: 28
|
I've just tried to trace the wire and...l it is #4awg coming off the isolator. From the battery to the master switch is 2/0, why I don't know as there is no inverter to power. Everything under the van is in plastic looming. I just spent several minutes trying to trace the wire only to find I was tracing a lpg line, in plastic loom!
I really want to know if the line from the house side of the isolator goes directly to the battery. I'm beginning to think it does not. It appears to be a black wire off the isolator and there are only red wires to the positive side of the batteries.
I'll keep exploring. Thank you!
|
|
|
07-16-2024, 02:25 AM
|
#28
|
Bronze Member
Join Date: Jul 2024
Location: Colorado
Posts: 28
|
Well after discussing this with multiple people on 3 different forums I think I'm pretty confident of my final solution (though I have to say I like Avanti's solution too!).
I think I will use a Victron 12/12/18amp DC to DC charger in place of the present battery isolator. Keeping it low amperage as I think this will help eliminate a lot of the stress on the alternator. This charger also has a remote switch so I can turn it off when the batteries are fully charged. The batteries have BT so I can easily monitor them.
I will also replace my MagnaTek 7445 converter/charger with a Boondocker BD12600 with the ability to adjust the output to match my lithium battery charging parameters.
Does this sound right?
Thank you!
|
|
|
07-16-2024, 06:19 AM
|
#29
|
Platinum Member
Join Date: Feb 2016
Location: Portland, Oregon
Posts: 3,307
|
Quote:
Originally Posted by avanti
I guess it is worth mentioning that another possibility to consider is a DC-AC-DC setup. In this approach, instead of a separate DC-DC converter, you just add a simple second inverter, powered by the engine. You feed the AC output of the inverter into the main house charger just as if it were shore power. That way, the house battery is always charged using the (presumably optimal) charge profile of the main charger, no matter whether the charge current is coming from shore power or the engine.
I went with such a setup because of its conceptual simplicity. I really like having one fewer charger to think about and program.
There are two things to note:
1) Of course, this system has an extra conversion step, and so is technically less efficient. However, this inefficiency only occurs when charging from the engine, which is an energy-rich situation, so it really doesn't matter much.
2) It is good if the main house charger is able to be easily programmed to limit the current drawn from shore power (and thus the charge rate). That way it is easy to limit the load on the engine to any desired level. This is a common feature of modern inverter/chargers.
I am very pleased with this setup. Worth considering.
|
I remember this concept from the Sprinter Forum extensively discussed many years ago, this was Dave Orton’s baby. You are stating a simple inverter, but sinewave inverter is likely required.
Dave also was one of the first promotors using 80/20 to build van’s cabinetry.
|
|
|
07-16-2024, 01:18 PM
|
#30
|
Platinum Member
Join Date: Aug 2010
Location: Minnesota
Posts: 12,456
|
Quote:
Originally Posted by Nobadays
Well after discussing this with multiple people on 3 different forums I think I'm pretty confident of my final solution (though I have to say I like Avanti's solution too!).
I think I will use a Victron 12/12/18amp DC to DC charger in place of the present battery isolator. Keeping it low amperage as I think this will help eliminate a lot of the stress on the alternator. This charger also has a remote switch so I can turn it off when the batteries are fully charged. The batteries have BT so I can easily monitor them.
I will also replace my MagnaTek 7445 converter/charger with a Boondocker BD12600 with the ability to adjust the output to match my lithium battery charging parameters.
Does this sound right?
Thank you!
|
Those parts will work well and safely, but will charge very slowly I think.
18 amps will take many hours to charge 200ah if they are down even 60% assuming full output the whole time, nearly 7 hours. Most I have seen on stock alternators have gone with about 40 amps, but for you to figure out if you can live with that slow of charging.
Same is true with shore charger which has a 13.4v fixed output that is too low for lithium at much rate if you use it that way, so you would into the 4 stage charging version which they don't say what the charge profile is. 4 stage is normally bulk/absorption/float/storage or recondition which is not great, but if it is bulk/absorbtion/off/rebulk it would be very good. It has a power supply mode so will recover a BMS shutdown if needed and can be switched on to that mode. Some that are both power supply and charger aren't very easy to change back and forth. Here is another model that is similar but has adjustable output voltage so you can set what you want. I use one for my home bench charger.
https://www.amazon.com/gp/product/B0...e?ie=UTF8&th=1
No matter what you decide to do with the above I would still add a battery monitor because you can't use voltage accurately for lithium to determine SOC.
|
|
|
07-16-2024, 01:25 PM
|
#31
|
Bronze Member
Join Date: Jul 2024
Location: Colorado
Posts: 28
|
Avanti... GeorgeRa.... My hesitation with going this route is the converter/charger I'm looking at draws 720w, or 60A. I can adjust the voltage output but I don't know if I could limit the the "current draw." So the alternator would have to supply that continually when charging. If the batteries were full no issue but if they need charged it could be a big pull on the alternator. There would need to be a charge controller between the charger/converter and the batteries to limit the draw. This seems like a lot of equipment to do a simple job.
Is there a specific converter/charger that you know of that can, "be easily programmed to limit the current drawn from shore power (and thus the charge rate). That way it is easy to limit the load on the engine to any desired level."
Thanks!
|
|
|
07-16-2024, 01:58 PM
|
#32
|
Bronze Member
Join Date: Jul 2024
Location: Colorado
Posts: 28
|
Booster... yeah know it would be slow charging with the alternator while driving but also easy on it. Most of out trips start from home where it has been plugged into shore power therefore fully charged. When camping we set out a portable -can be easily aimed- 75w solar panel to provide charging each day. We also have the option of the generator or RV park shore power.
The Boondocker BD12600 in lithium mode allows a constant output of a user set voltage between 13.2v and 16.5v. The batteries I will be using recommend 14.4v.
That said, thank you for another recommendation for a converter/charger! I looked over a lot of them on Amazon but just couldn't land on one that I could adjustthe output, most I found are set at a fixed output of 14.6v which is too high in my opinion. I see this one has an adjustable, fixed output in lithium mode. Much cheaper! Sweet!
I'm still not ready to pull the trigger as I kind of like the method Avanti is using. My concern is, again stressing the alternator. I value your knowledge on this subject, any thoughts on using an inverter directly off the Chassis Battery to power the on-board converter/charger? Can the C/C you recommended be "dialed back" so it doesn't draw heavily on the inverter.... or is that a function of how you have set the charging output?
Thank you!
|
|
|
07-16-2024, 02:18 PM
|
#33
|
Platinum Member
Join Date: Aug 2010
Location: Minnesota
Posts: 12,456
|
Quote:
Originally Posted by Nobadays
Booster... yeah know it would be slow charging with the alternator while driving but also easy on it. Most of out trips start from home where it has been plugged into shore power therefore fully charged. When camping we set out a portable -can be easily aimed- 75w solar panel to provide charging each day. We also have the option of the generator or RV park shore power.
The Boondocker BD12600 in lithium mode allows a constant output of a user set voltage between 13.2v and 16.5v. The batteries I will be using recommend 14.4v.
That said, thank you for another recommendation for a converter/charger! I looked over a lot of them on Amazon but just couldn't land on one that I could adjustthe output, most I found are set at a fixed output of 14.6v which is too high in my opinion. I see this one has an adjustable, fixed output in lithium mode. Much cheaper! Sweet!
I'm still not ready to pull the trigger as I kind of like the method Avanti is using. My concern is, again stressing the alternator. I value your knowledge on this subject, any thoughts on using an inverter directly off the Chassis Battery to power the on-board converter/charger? Can the C/C you recommended be "dialed back" so it doesn't draw heavily on the inverter.... or is that a function of how you have set the charging output?
Thank you!
|
The chargers in the link I gave are fixed output for amps so can't be limited at the charger.
Avanti's method had been discussed here a few times before I put our lithium conversion together. I had seriously thought about doing it quite some time ago, even on our big AGM 440ah system that we had before.
As it turns out, before I got around to considering a lithium sway, Wakespeed came out with a remote alternator regulator that has the ability to amps based charging by using a shunt to measure actual battery charging amps. We have two alternators so I run the 280amp one on the Wakespeed and leave the van system stock. I can set charging current, voltage, hold times, etc in the Wakespeed, but for some reason it can't be made to go silent instead of float. I added a Victron monitor and used the internal contacts to shut off the ignition trigger on the Wakespeed based on the Victron SOC. It is set to come on at 35% and go off at 80% while driving. It works very well for us and requires no B to B or extra inverter and take no real amount of space as the Wakespeed in under the passenger seat and in very small besides compared to the others. It also requires no large cables to run to it, as all it does is control the field of the alternator to regulate things. Big cable goes direct to the alternator from the battery with a manual disconnect and a spike protector in line.
For me, if not for the direct regulation solution, it would be a serious consideration to use a the DC/AC/DC setup, but we have plenty of excess alternator capacity available. You would probably need to decide if the extra layer of introduced inefficiency would be taxing you available alternator too much for your comfort zone. Of course larger alternators are readily available for your van also.
|
|
|
07-16-2024, 03:42 PM
|
#34
|
Site Team
Join Date: Jul 2013
Posts: 5,428
|
I am using a Victron Multiplus, which allows you to arbitrarily limit the current draw from shore power. But, this is a rather large hammer given your goals.
Dave Orton used the Magnum MMS1012, which I believe also has variable current settings. Still a bit pricy, but you would end up with a very capable (and simple) system.
Note that you will never get a load on your engine much larger than the max current of whatever you plug into the second inverter. So, if you are really happy with an 18A charger rate, this will never be an issue--just get a tiny converter/charger. The downside would be that you would be limited to this charge rate even when on shore power.
__________________
Now: 2022 Fully-custom buildout (Ford Transit EcoBoost AWD)
Formerly: 2005 Airstream Interstate (Sprinter 2500 T1N)
2014 Great West Vans Legend SE (Sprinter 3500 NCV3 I4)
|
|
|
07-16-2024, 04:15 PM
|
#35
|
Platinum Member
Join Date: Aug 2010
Location: Minnesota
Posts: 12,456
|
Quote:
Originally Posted by avanti
I am using a Victron Multiplus, which allows you to arbitrarily limit the current draw from shore power. But, this is a rather large hammer given your goals.
Dave Orton used the Magnum MMS1012, which I believe also has variable current settings. Still a bit pricy, but you would end up with a very capable (and simple) system.
Note that you will never get a load on your engine much larger than the max current of whatever you plug into the second inverter. So, if you are really happy with an 18A charger rate, this will never be an issue--just get a tiny converter/charger. The downside would be that you would be limited to this charge rate even when on shore power.
|
The Magnum would probably work, but would need a remote to do the settings, probably an ARC-50 which is expensive and may require a BMK monitor kit also, and the MMS1012 will only be able to use up to the level 3 settings the ARC can do. That said, our Magnum MS2012 which is 100 amps charging and 2000 watt psw inverter has some issues with the lithium high acceptance rate and early cut out. I think it has to do with voltage sensing and the fact that you can only set to .1v instead of the .01v that would be much better for lithium. I need to move my voltage sense to get it right on the batteries to see it that helps as I had it a ways away with the AGMs when it didn't make much difference at all.
If 18 amps of charging is enough, and 75 watts of solar can mostly keep up, I assume, as you would want to limit generator run times, it just seems that power use would be pretty low. The question would be if lithium is really needed in this case, as long as you don't have some very high load needs like running a microwave or cooktop. It seems like 200ah of AGM would do fine if no big load bursts.
|
|
|
07-16-2024, 04:20 PM
|
#36
|
Platinum Member
Join Date: Oct 2018
Location: MN
Posts: 520
|
Quote:
Originally Posted by Nobadays
That said, thank you for another recommendation for a converter/charger! I looked over a lot of them on Amazon but just couldn't land on one that I could adjustthe output
|
If you end up with a Victron DC-DC, then going with a Victron shore charger makes sense, as they will use the same app & can be configured identically. Victron's Blue Smart 30 amp IP-22 charger is a good choice, as would be their "Smart IP43 Charger 120-240v".
I have a Victron 18amp DC-DC & Redarc 40 amp DC-DC in parallel, and a 30 amp IP-22 for shore charging. If I were starting over, I'd get a Victron Orion XS 50 amp DC-DC charger and a 30 amp IP43 shore charger & eliminate the Redarc.
|
|
|
07-16-2024, 04:35 PM
|
#37
|
Platinum Member
Join Date: Feb 2016
Location: Portland, Oregon
Posts: 3,307
|
Quote:
Originally Posted by Nobadays
Avanti... GeorgeRa.... My hesitation with going this route is the converter/charger I'm looking at draws 720w, or 60A. I can adjust the voltage output but I don't know if I could limit the the "current draw." So the alternator would have to supply that continually when charging. If the batteries were full no issue but if they need charged it could be a big pull on the alternator. There would need to be a charge controller between the charger/converter and the batteries to limit the draw. This seems like a lot of equipment to do a simple job.
Is there a specific converter/charger that you know of that can, "be easily programmed to limit the current drawn from shore power (and thus the charge rate). That way it is easy to limit the load on the engine to any desired level."
Thanks!
|
I don’t know which inverter has adjustable current draw; I am not following this very dynamic market. I would suggest to contact https://www.donrowe.com/ folks, they should know.
I recently purchased new 2x115Ah AGM Fullriver batteries replacing over 11 years old ones. I couldn’t justify changing my Magnum/Morningstar system to change from AGM lead acid charging requirements to lithium. At some point someone (perhaps Victron) will come out with a Li programmable charger capable to take DC/PV, DC modern car alternator and shore AC, then I will reconsider in the next 11 years.
|
|
|
07-16-2024, 06:33 PM
|
#38
|
Bronze Member
Join Date: Jul 2024
Location: Colorado
Posts: 28
|
All good information. I think I will change to a higher output DC to DC charger, the Victron 12/12/30amp smart charger. In addition, though I would love to go all Victron, they don't make a converter/charger similar to the current one I'll be replacing. So I think the Power Max PM3-45 suggested by Boomer will fit the bill.
Thanks all!
|
|
|
07-17-2024, 12:27 AM
|
#39
|
Platinum Member
Join Date: Dec 2017
Location: Arizona
Posts: 1,215
|
Nice discussion. I'm confused. On my 97PW I have the 1202 isolator. IIRC the cables for the alternator and starter battery are heavy gauge and the one on the isolator going back to the cabin battery is a lesser gauge (8?).
Would it be possible to simply remove the isolator and bus-bar connect those 3 connections (with appropriate fusing)? Then place a B2B fed off of the original wiring in the rear of the RV near the cabin battery? And since I have a 40A breaker originally on that line, would it be safe to assume a 40A B2B would not require upgrading that wiring?
IOW why would you need the isolator in the picture at all?
Just wondering
Thx.Glenn
|
|
|
07-17-2024, 01:07 AM
|
#40
|
Bronze Member
Join Date: Jul 2024
Location: Colorado
Posts: 28
|
I can't answer your questions but will add...
I think the wire fron the isolator back is 4awg on my 2000 Excel TD. Somewhere in the rear it changes as I'm pretty certain both sides of the red master switch are 2/0, with 2/0 to the battery. I may be mistaken these might be 2awg but bigger than 4awg. Where it changes I have no idea but one side goes to the battery and it is protected by an 80amp breaker that is labeled "80 amp charge line" with this big wire on each side. There is also a breaker there labeled "30 amp power conveter" these are I believe 8 or 10awg. ( I'm used to working with residential off-grid solar where we use primarily 2/0, 4/0 and 10awg, sometimes 6 or 8awg but not often.)
I do like your idea of a busbar to connect the existing wires back to... alternator output, Chassis Battery and a line to the DC to DC charger. It would make clean in place of the Isolator.
I have wanted to do what you describe but I'm unclear exactly which wire is coming from the isolator and if it makes other stops along the way. I found it impossible to trace it under the van.
We wait for those who know more!
|
|
|
|
|
Posting Rules
|
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts
HTML code is Off
|
|
|
|
» Recent Threads |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|