Converter in new Micro Minnies

[creativepart]

Originally Posted by Bigbird65

BobC I looked here but could not find the thanks message: "The Thanks messages are found in the User CP, just below the private messages."

I had trouble finding it. Try this:

Click on User CP on the menubar
Then scroll all the way down the page... keep going, keep going.

There you'll see it at the bottom of the page in the main column. It's not a link, just the Thank Yous you've received. Above it will be "Subscribed Threads"and "Subscribed Forums" if you have any. Again, not links to those things but listings of every thread (or forum) you have subscribed to.

[Bigbird65]

creativepart, thanks I found several thanks.

[Fred 2106DS]

Originally Posted by creativepart

Yes, I too have no idea of how the Thanks messaging works and I’ve worked with this software on a dozen forums for 20 years. There are many smaller subsystems that are mostly ignored like, Profile Messaging, and others that 99% of us never take any notice of.

FYI - I receive an email when I receive thanks or a private message. Also, when I log into this forum I get a pop-up telling me I have a new private message. In addition to the pop-up message, in the header area on the screen it shows if I have unread private messages, see below.

[MadMaxWinny]

Back on track, @Grogers: Since your RV is new, it almost certainly has a 3-4 stage charger (converter). The 2 stage "trickle chargers" pretty much went the route of the dinosaur in the 80's (although they COULD be found on Winnebago's up until the mid 2000's). If you've got flooded batteries, it's still a good idea to check the electrolite in the individual cells twice a year, adding distilled water, when necessary. Cheers!

[BobC]

Originally Posted by MadMaxWinny

Back on track, @Grogers: If you've got flooded batteries, it's still a good idea to check the electrolite in the individual cells twice a year, adding distilled water, when necessary. Cheers!

Based on my personal experience and from what I've read, twice a year is not frequent enough. However, this has a lot to do with a lot of factors, including your weather, how you use your batteries, etc. Whether or not you disconnect them or not or leave them attached to a charger is also a factor.

I'd suggest starting out monthly and go from there depending on what you find. And, you should always check before going on a trip.

[Bigbird65]

Originally Posted by MadMaxWinny

Back on track, @Grogers: Since your RV is new, it almost certainly has a 3-4 stage charger (converter). The 2 stage "trickle chargers" pretty much went the route of the dinosaur in the 80's (although they COULD be found on Winnebago's up until the mid 2000's). If you've got flooded batteries, it's still a good idea to check the electrolite in the individual cells twice a year, adding distilled water, when necessary. Cheers!

I would recommend checking the electrolyte at least every 2 months and more often in the hottest months. Easy to do.

[MadMaxWinny]

While checking more often will certainly catch a runaway charger, the "real world" hope that everyone checks twice a year is usually sufficient.

[fringemtm]

I just stumbled across this while looking for an easier/cheaper way to upgrade to Lithium batteries. WFCO has a new converter that will auto detect what type of battery (LA/LI) you have and charge it accordingly to preset numbers. here's the link to WFCO - https://wfcoelectronics.com/auto-detect/ and to purchase the converter - https://parts.unitedrv.com/collectio...wf-8955-ad-mba

[sidpost]

Even cheap modern Charge Controllers and Battery Maintenance Systems will recognize the major battery types and default to reasonable charge parameters. It is still best to 'adjust them' to the values the battery manufacturer recommends.

[MadMaxWinny]

Well. The only thing that comes to mind for "automatic battery type" detection is internal battery resistance. Making a gross distinction between Lithium/Flooded doesn't sound impossible, providing we are taking about new batteries, since internal resistance is not a fixed value. I would have to see a comprehensive bench test with a resulting table of voltages before I risked it. I wouldn't get one anywhere NEAR a Gel battery.

[sidpost]

Originally Posted by MadMaxWinny

Well. The only thing that comes to mind for "automatic battery type" detection is internal battery resistance. Making a gross distinction between Lithium/Flooded doesn't sound impossible, providing we are taking about new batteries, since internal resistance is not a fixed value. I would have to see a comprehensive bench test with a resulting table of voltages before I risked it. I wouldn't get one anywhere NEAR a Gel battery.

I run Flooded, AGM, and LiFePo4 batteries. My Charge controllers have recognized them all and preselected appropriate charge/discharge parameters.

Would I trust cheap controllers off eBay or out of China? No!

Midnite Solar, Victron, and Schneider Electric are all solid choices. Midnite Solar is a domestic USA company so for myself, it is the place I start when looking for solar hardware. Samlex Inverters are the best I have personally used though, I'm hearing good things about Midnite Solar in larger capacity inverters.

Saying all this DOESN'T mean I won't check things and blindly trust some 'black box' to figure it out and trust everything is good.

[MadMaxWinny]

Have you checked the final float mode voltages? That is where the danger exists.

You can charge Flooded and AGM with the same charge algorithm with little ill effect since they are so close (but not as efficient). I run AGM in everything and do not adjust the alternator voltages in my cars, boat, RV. Lithium and Gel are totally different creatures.

Once upon a time when AGM was new to non-military applications, I was hired by a sailboat builder in FL who switched to AGM on all of their new boats and had very mixed results. I was perplexed to find that almost half of the boats had catastrophic premature failures. It turned out that they used two boatyards for final commissioning, and one yard set the Xantrex inverter/chargers to Gel cell, since the batteries were the same color! The higher Float mode voltage cooked the AGMs, over time.

[sidpost]

Originally Posted by MadMaxWinny

Have you checked the final float mode voltages? That is where the danger exists.

You can charge Flooded and AGM with the same charge algorithm with little ill effect since they are so close (but not as efficient). I run AGM in everything and do not adjust the alternator voltages in my cars, boat, RV. Lithium and Gel are totally different creatures.

Once upon a time when AGM was new to non-military applications, I was hired by a sailboat builder in FL who switched to AGM on all of their new boats and had very mixed results. I was perplexed to find that almost half of the boats had catastrophic premature failures. It turned out that they used two boatyards for final commissioning, and one yard set the Xantrex inverter/chargers to Gel cell, since the batteries were the same color! The higher Float mode voltage cooked the AGMs, over time.

Yes, I verify the settings against the battery manufacturer ratings as a single battery type often has a 'range' of differences for optimal battery maintenance. I verify with a DMM, not the charge controller display FWIW.

If your settings are in the right 'range', you will generally only affect efficiency and generally lightly affect battery life. If you select the wrong type, depending on battery type versus 'battery charge type' can lead to off-gassing explosions or battery fires.

This is why you have 'burn bags' for laptops on commercial air flights. A fire in an airplane or on a boat is super scary with few good options when it happens.

At a bare minimum, you need to verify the battery type selected on the charge controller matches the battery type in your battery box. Having that sort of installation failure you mention could be catastrophic, not just financial due to short battery life. NEW INSTALLS MUST BE INSPECTED FOR THESE TYPES OF FAILURES.

[BK1]

Hi all,
Brand new here.
Stumbled across this thread while looking for info on converter chargers.
I'm also new to travel trailers, so please excuse any ignorance.
Recently bought a 2018 Micro Minnie 2106FBS. Proceeded to ditch the battery and replace with 2× Renogy 12V 100ah lithium iron phosphate.
Also have 2 × 100 watt panels with a charge controller. The solar stuff is working great with the batteries.
My issue is with the charge that I'm getting (not getting) while driving AND while plugged in to shore power. In both scenarios, the batteries only charge to about 70%. Is that because the converter charger isn't fully compatible with lithium? Can this be easily solved by switching to a different converter charger?
Look forward to hearing some thoughts on that.
Thanks in advance.
Brent

[creativepart]

Originally Posted by BK1

Is that because the converter charger isn't fully compatible with lithium? Can this be easily solved by switching to a different converter charger?

YES! That's what's needed. Your converter is not putting out enough amps nor the correct voltage. Replacing the converter with a Li capable unit will fix the shore power charging issue.

To fix the charge while you drive problem you'd likely need to add a DC to DC charger. It will take the meager power from your TV's connection at the 7-way pin and convert it to a higher amperage LiPo specific charge profile.

That's RVing for you - there is always more things to spend money on.

[BK1]

Thanks Creativepart.
So I actually bought a Renogy DC-DC charger, thinking it would be able to be wired through the 7 pin connector. Manual disagrees. Needs to be wired to both the alternator and the ignition circuit and requires 4 AWG wire for the length of wire that would be required. After reading that, I started looking at converter chargers.
Wiring diagram attached.
Is there an easier way?
Again, appreciate your help.
bk

[creativepart]

Not with the Renogy. Victron doesn't need a trigger wire to the ignition. It can turn on and off automatically because it senses voltage from the alternator. However, I don't know about heavier gauge wiring. That's part of the problem with your stock tow vehicle. The long run of inadequate wiring reduces the amount of charge current you receive.

There are some YouTube videos of setting up D2D chargers for travel trailers. You might look there.

[sidpost]

Originally Posted by BK1

Hi all,

Recently bought a 2018 Micro Minnie 2106FBS. Proceeded to ditch the battery and replace with 2× Renogy 12V 100ah lithium iron phosphate.
Also have 2 × 100 watt panels with a charge controller. The solar stuff is working great with the batteries.

My issue is with the charge that I'm getting (not getting) while driving AND while plugged in to shore power. In both scenarios, the batteries only charge to about 70%. Is that because the converter charger isn't fully compatible with lithium? Can this be easily solved by switching to a different converter charger?

You really need a better quality Charge Controller to start. Midnite Solar and Victron are two manufacturers to consider. I find the Midnite Solar KID to be a very flexible and easy-to-use option. The Victron units are high quality as well but, they aren't as user-friendly out of the box IMHO.

You need to go to your charge controller's battery voltage menu and input the values appropriate for your battery if it doesn't "auto-sense" you are on Lithium.

A DC-DC voltage converter will allow you to connect your tow vehicle's 12Vdc system to your Lithium battery's voltage to allow recharging while you travel. 10 or 12 gauge wire should be able to handle a reasonable current load while you travel. I would think ~10A for charging as you travel down the road would be plenty fast enough for most applications. You don't need or want the current load a 4gauge wire will provide.

[Fred 2106DS]

Originally Posted by BK1

Thanks Creativepart.
So I actually bought a Renogy DC-DC charger, thinking it would be able to be wired through the 7 pin connector. Manual disagrees. Needs to be wired to both the alternator and the ignition circuit and requires 4 AWG wire for the length of wire that would be required. After reading that, I started looking at converter chargers.
Wiring diagram attached.
Is there an easier way?
Again, appreciate your help.
bk

Hi BK1, Here's a couple of links you may be interested in. This link describes my installation of the Renogy 20A DC-DC charger, I used the Micro Minnie's clearance light circuit as my trigger source for the DC-DC charger. This second link describes the latest charging tests I ran with the 7 pin connector and DC-DC charger. We also have 200AH of LiFePO4 batteries.

Fred

[BK1]

Thanks Sidpost.
But the solar stuff is working great.
I haven't mentioned my solar charge controller, but yes I've set the parameters on it and it's working great with my batteries.
It doesn't have anything to do with my issues of charging while driving and while plugged in to shore power.
Am I missing something?