Is a DC to DC Charger Really Needed?

[dkoldman]

Originally Posted by Morich

Sounds right but I'm no help on the size!
Getting space may be a problem and one to consider is how to get to the Trombetta and battery disconnect if there were ever a real need. The solenoid is know as a potential troulbe spot as it opens/closes every time we start the engine and that causes small arcs every time. Not to say it fails soon but you may at some point want to get there, so nothing permanent that blocks the path?
One point on the grounding is that most any metal of the box/compartment is likely welded to the rest of the metal, so no need to go to actual frame of the RV. Basic idea is to keep all grounds at the same level but most of the solid parts are attached to the frame. Things like their major buss bars are often welded or bolted direct on the frame. The copper buss bars is something they can make all the holes for the smaller wires and then attach it to the frame but there are often at least two!
Maybe just clear the paint off at a handy point and then makes sure the attachment bolt, etc. is never coming loose?
Second thought? That wire FM is laid on the mounting screw of the Trombetta and they use the mount as ground as well as the wire, so double on the same point would be good!
Test before trusting!

Yes it helps to know the drawings are right.

I believe in the 7Ps Prior, Previous, Planning, Prevents, Piss, Poor Performance. I am going down this road because the opportunity to buy Lithium batteries are actually a lot cheaper than buying AGMs tomorrow.

My goal right now is to get this all setup and working with my existing AGMs, then later buy 2 new 100ah Lithium and simply change profiles on Renogy and new to be determined Converter.

Back to the picture of Chassis cabinet. Do you think it is okay for a DC to DC to be stored inside? It is not air tight but when the breaker panel is screwed back on, it will be closed?

On ground, this is confusing to me, because it just seems like the wires for Renogy are a lot thicker than what the Victron can even accept? I was thinking that it may have to 6awg or similar. Since it is common ground (negative) Could I simply run one black ground wire from Input Ground post to the Output ground post and the then run a separate wire from one of the two post to the cabinet wall? As luck may have it, two screws on the left side at the top are actually mounted the cabinet to the frame. I may just need a washer to help cover the lug. Of course this assume I can amount inside the cabinet.

I was going to replace the Trombetta in favor of the LI-BIM, but as time passes I don't like the concept stopping for 20 minutes after 15 minutes of use. If the Trombetta fails I will just replace.

But if I following how this may work, I will not physically be using the Trombetta contacting any more unless I need to jumpstart chassis battery? i.e. Assume I split LR in front of the trombetta. I will them LR1 & LR2 I can put a switch on both LR1 and LR2.
LR1 - Goes to the Trombetta
It will always be OFF (Open on Trombetta, I will call Normal mode 99.9%)

LR2 - Goes to the Renogy
It will always be ON (So when ever LR is hot it turns ON the Renogy

If I flip switch LR1 to ON and hold the AUX / START button the Trombetta should make contact and I should be able to start the Engine. When running I go back and flip LR1 switch back OFF.

LR2 will have switchtoo, but it really would NOT be needed unless it was some event and I wanted to ensure the Renogy did not come on

[Morich]

For the ground, my thought is that the frame and any metal like metal compartments that are solidly attached to frame are all quality grounds.
That leaves the main problems with getting and keeping a good ground, not so much in where and what things are grounded to but more how good we can keep the connection!
That is like when we think of running power and ground to a car to tow. Some favor running power and ground wires from the trailer hitch to the batteries that may be half way up the RV. Since the negative side of the battery is on the frame, I feel running a short wire to the frame at the rear of the RV is better as it is like a super think, really solid bar of steel connected to the battery! Lots less resistance in a 12" steal frame than in a even a number 6 wire!
You COULD run a wire all the way to the battery but there is already a big hunk of steel going over there, so I run the shortest distance.

For the question of needing ground at two different points, it really should not matter at all which you go to first. From ground to point A and then to B is the same as ground from B and then to A!
As long as the connections are good and don't get loose or corroded, the frame, A, and B are all the same for electrical use. The more we can keep connections off the battery and away from acid fumes, the less they corrode. But the new batteries tend to do away with that problem!
If you use some reasonable size wire, the wire between A and B is not going to be enough to tell the difference. Our RV are just too short! Number 14 is often handy to work and plenty big. Lots of the trailer hitch connection is 16 gauge but that get fussy for me to work and breaks a little too easy for me to like it.

[dkoldman]

Originally Posted by creativepart

I have disconnected my alternator charging at the BIM that my motorhome came with. So, I installed a DC2DC charger (Victron Orian 30-amp) and I have 300w of solar on my roof. The 400ah of LFP batteries do a remarkable job of powering things, including my residential 110v fridge that only runs off of my inverter and even my microwave, the coffee maker, etc. We've made no attempt to power A/C with inverted power.

The 300w of solar I have does such a good job of charging those batteries while driving that the DC2DC charger really doesn't play all that much of a role. I kind of which I had installed the Li-BIM and skipped the whole DC2DC charger thing because I had to make up for a loss of chassis battery charging while on shore power from my OEM BIM and I lost the Aux Battery Combining function entirely when I disconnected my BIM.

I hope this helps answer some of your questions about these issues. The most important part is making the change to LFP batteries. They truly are a game changer.

With more insight, I wish to circle back on your choice of Victron Orian 30amp. Discounting LI-BIM because at the moment I don't think that option is good for the way we use the coach. If engine is running I want to ensure my House batteries are getting some type of charge 100%.

Even though I have already ordered the Renogy 40amp, I am still trying to compare the with Victron 30amp. I got a brand new Renogy for $100, so I am not that deep in with Renogy. I would like your thoughts on the comparison assuming that DC to DC was the plan. May not be a far analysis since you already bought Victron, but I would appreciate the insight.


My thoughts are below...

Pros Renogy
1. Cost $100
2. 40 amps

Cons Renogy
1. Size
2. Needs Ignition wire
3. 5 wires to connect
4. Bluetooth is separate option

Pros Victron
1. Auto Sense
2. Smaller footprint ( 3 inches shorter)
3. 3 wires to connect
4. Comes with Bluetooth app
5. Ability to turn On/Off with the app

Cons Victron
1. Price $180
2. Only 30 amps

[creativepart]

I went with the Victron Orion because I have a Victron SmartShunt and a Victron Solar Charge Controller. So having it all on one app was a plus. But mostly it was the auto sensing feature. It makes installation so easy. You can put it anywhere almost.

30-amps has been plenty. They do now make a 60-amp model, I think.

I inadvertently bought the isolated version but either will work so I used that one.

[dkoldman]

Originally Posted by creativepart

I went with the Victron Orion because I have a Victron SmartShunt and a Victron Solar Charge Controller. So having it all on one app was a plus. But mostly it was the auto sensing feature. It makes installation so easy. You can put it anywhere almost.

30-amps has been plenty. They do now make a 60-amp model, I think.

I inadvertently bought the isolated version but either will work so I used that one.

Does this item look legitimate to you?

I question the UK, CA next to serial number and I also noticed that it does not say 12 / 12 / 30 on the top of the unit in white letters like the others that I see.

I see the large heat sink, but I do not see a fan?

Seems like Victron does not have National Support; so you have to call a Dealer.

[dkoldman]

Originally Posted by dkoldman

I sent some questions to precision circuits about the LI-BIM although I think I have the answer to one of them. It looks like the LI-BIM will always send power to the Chassis battery so the 20 minute timeout is only for the House battery. So I should not have to worry about my jacks losing current when engine and possibly the slide if it is in fact on Chassis battery too.

My questions to Precisions Circuits

1. My current wiring had the Ignition and the Boost Hot on the same wire 'LR'. If I connect that wire to your IGN post; will it be okay if the SIG post is empty? The ground, chassis and coach cables will be connected. Will it work that if I hold AUX/START I can use the Lithiums to help start the chassis battery

2. How does the LI-BIM 225 prevent overcharging the Chassis battery when on SP/Genny when the House battery is calling for full boost 14.4vdc?

3. If I have the LI-BIM 225 installed, how do I ensure that it will not go into rest state or come out of rest state in order to operate the Hydraulic Jacks and/or Slides? Currently per Winneabgo operating manual, the engine must be running to operate Jacks and/or slides. This is to ensure the alternator is running so full voltage / current is applied. Seems like with LI-BIM 225 it could happen to go into a rest state right in the middle of operations. Is there something to prevent or ensure max power before operating?

Below is response I got from Precision Circuits this morning to the questions above after I had told them I had standard F-53 Chassis and plan to buy two 100ah Lithium. The best I could find earlier on alternator size was 175.

The first things you have to find out is the size of the alternator then the Lithium battery spec for “Max Charge Rate”. You can only use the Li-BIM if you alternator does not exceed the max charge rate of the Lithium battery bank. If your alternator is able to exceed the max charge rate of the Lithium battery bank you will have to look into using a DC to DC charger.

[Morich]

My best guess would be the UK/MEANS UK and Canadian standards? I would not expect too much difference but possibly more metric things like screws, etc?
Maybe you need to match it to a Winnebago that has Canadian standards as well!!

Sorry! Ignore that as you don't need more grit in the mind>>>>

[dkoldman]

I am going to update this for future.

Of note is I tried to called Victron but got referred to a Dealer, the dealer didn't have knowledge or interest to answer my question as I was not a customer which I follow, but point is I didn't get any info on Victron DC To DC

By contrast I had a 5 minute hold and had a 10 minute conversation with Renogy and all questions got answered. Some answers were not good and I will reflect below.

Pros Renogy
1. Cost $100
2. 40 amps
3. They confirmed a common ground can be used for both negative posts
4. Excellent phone support

Cons Renogy
1. Size
2. Needs Ignition wire
3. 5 wires to connect
4. Bluetooth is NOT an option
5. Cannot be mounted upside down
6. Cannot mount in area with poor circulation
7. Cannot mount in Battery compartment if concerns with dust maybe moisture


Pros Victron
1. Auto Sense
2. Smaller footprint ( 3 inches shorter)
3. 3 wires to connect
4. Comes with Bluetooth app
5. Ability to turn On/Off with the app

Cons Victron
1. Price $210
2. Only 30 amps
3. No phone support
4. Need an external fan to prevent overheating

[creativepart]

I got mine through the "Victron Energy Store" on Amazon;

https://www.amazon.com/Orion-Tr-12-3.../dp/B07ZKG396Y

Not sure where you got the "needs external fan" from but I don't have one on my setup and never had an issue.

EDIT: I did some looking and see that many people do add fans and that the Orion output decreases when it gets too hot.

My install is free from wet weather but has a ton of air flow around it. Keep in mind with solar charging while driving the Orion doesn't have to do a lot of work. Plus, I don't deplete my 400ah of battery storage very much between stops. So, this isn't an issue that I'm too concerned with.

[dkoldman]

Originally Posted by creativepart

I got mine through the "Victron Energy Store" on Amazon;

https://www.amazon.com/Orion-Tr-12-3.../dp/B07ZKG396Y

Not sure where you got the "needs external fan" from but I don't have one on my setup and never had an issue.

EDIT: I did some looking and see that many people do add fans and that the Orion output decreases when it gets too hot.

My install is free from wet weather but has a ton of air flow around it. Keep in mind with solar charging while driving the Orion doesn't have to do a lot of work. Plus, I don't deplete my 400ah of battery storage very much between stops. So, this isn't an issue that I'm too concerned with.

This was one of the things I wanted to ask Victron about, I may have to try to call other dealers. It makes for awkward conversations if you are just trying to get information and they are just trying to sell product. Which comes first the chicken or the egg.

This is where I first saw the fan. Skip to the 8:45sec mark

https://www.youtube.com/watch?v=kmf3jc-gAFA&t=682s

I assumed it was external; then I saw the fan included with some listing so I don't know if it comes in the box or not? See second picture of this unit

https://www.ebay.com/itm/285921685048

If I need a fan it loses it value over being smaller. The unit / model with the fan also have the UK/CA so it comes with those models.

Maybe I get lucky and find a dealer that not only helps, but sales one at a fair price. I wish the Renogy had input and output post all on the same side, it would allow you to get into a smaller space.

[Morich]

Part of the problem I've run into with installing different equipment in mobile stuff. The folks who design it may have huge spaces in mind like on ships but when I want to install it in something like a cargo van, space is premium and not considered in their design!
Sometimes you get really what seems logical to them but not workable at all fo us!
They put input an doutput connections on different ends of the box and becasue they don't want them close together to short across?
Good idea but in real life we want to run the two cables, in and out, both through the same grommet into a compartment and keeping them separated on different ends burns precious space! BUMMER!

[creativepart]

Originally Posted by dkoldman

I assumed it was external; then I saw the fan included with some listing so I don't know if it comes in the box or not?

No fan comes with the charger. As I said, I see others have started adding them, but the installation instructions make zero mention of a fan and unless you're installing it in a hot location I would not plan on needing one.

That second photo just shows the sizable heat sink on the back of the charger. No fan there.

Many of the YouTube videos are van lifers that install a ton of other "hot" equipment in a small cabinet and do have cooling needs.

[dkoldman]

Originally Posted by creativepart

No fan comes with the charger. As I said, I see others have started adding them, but the installation instructions make zero mention of a fan and unless you're installing it in a hot location I would not plan on needing one.

That second photo just shows the sizable heat sink on the back of the charger. No fan there.

Many of the YouTube videos are van lifers that install a ton of other "hot" equipment in a small cabinet and do have cooling needs.

You guys are watching me grow in real time. I spent last night researching the new Orion XS 50 Amp. It is a game changer. When I throw out the $328.10 cost it is by far the best for what I need. I had not received my Renogy yet, but as the moment as soon as I do, I will try to put it up for sale.

But the Orion XS attract me because
1. Smallest footprint about 1/4th the size of the Orion TS 30 amp
2. It does 50 amps and is adjustable to 40 o 30 amps etc.
3. it is 97% efficient so it does not overheat
4. It is dust and water proof
5. Auto sensing of engine running
6. Simpler wire connections, no lugs needed and a collar to help hold the wired firmly
7. GX communications
8. Shows input and output current in the app
9. Shows status of bulk, absorption, & Float modes

Assuming I buy 2 60amp resettable breakers, I can turn on/off physically whenever I like in addition the app

I may wait before ordering hoping they put it on sale. Maybe I get lucky on Prime day.

[dkoldman]

Originally Posted by Morich

Yes, I have much the same questions on the SIG wire and what it does versus what the IGN wire does? It will likely need a call or talk to somebody who knows what they put in side their product!
Part of it is something I've never looked at and may not be available. Do other RV besides Winnebago use something similiar to what we have on solenoid, BIM, etc?
My thought is that other RV may have a different setup for charging the coach while driving and what we find may not have been what they were working with in their design thinking!
But that is where I tend to have alove /hate thing with solid state! I grew up with the old stuff like points and plugs on cars. they gave a ton of trouble but when they stopped working right, you could use a fingernail file and may the points work again.
Now if I had trouble with my car, I would have little choice but to take it to a shop where they hook it to a machine to find what to do!

On the batteries, do they come with any kind of cold cranking amps (CCA) rating? That is what I use to judge how much instant power we can get, where the amp hours is more how mcuh total between full and discharged.
And that also gets back to the new gizmo being discussed! When you have the current solenoid, there are big contacts that can carry lots of current from the coach to start the RV. But what is in the new and how much current at one time can it pass?
Any engineers for the company that like to explain things???

I ruled out a LI-BIM. If I made that change I would have to big bang my Lithium conversion and buy all new batteries now. I also verified with Power Gear that I would be rolling the dice that I needed to use slide or be in the middle of using slide when the LI-BIM went into that 20 minute rest state. I also didn't like the fact that the charging profile would only be 90% of actual capacity. It did not help matters that the Precision Circuit tech I talked to could not give me a straight answer on Sig post for LI-BIM

[dkoldman]

Today I received and installed my new Progressive Dynamics Converter / Charger https://www.progressivedyn.com/product/pd9345/

It not only will provide me the flexibility to change profiles, but I learned that it has a special profile for AGM which is more efficient than the FLA profile. It also came with a Pendant for boosting on demand, but I have never needed that. My batteries with AGM typically never dips below 12.4vdc. With the new program, absorption is now 14vdc on my AGMs; so I suspect I may get more faster if not better performance from the existing batteries that were peaking out on 13.6vdc.

In future, if I ever do by Lithium batteries, I can simply change the profile and it goes up to 14.4vdc

My next steps are to install the new Yitranic Inverter which kind of started all of this. The Inverter brand is a gamble, it is due next week so we will see.

I also have new safety switches on order. https://www.amazon.com/gp/product/B0...0?ie=UTF8&th=1 When they come, I will install one on the ignition wire that feed the Trombetta on the outside compartment Chassis breaker panel. This will give me the flexibility to turn off charging of chassis batteries through the solenoid while driving if I ever needed to shut it down, i.e. if I ever install a DC to DC system.

Speaking of DC to DC, I have my brand new Renogy 40amp DC to DC, but thus far, I have chose to not open it. I will look to sell it while I search a way to get the new Victron Energy XS 50amp DC to DC.

Hopefully by this time next week my new replacement inverter is installed an d working, and my coach is Lithium ready just waiting a DC to DC system to be installed.

Because my vMax tanks are still in good shape, I am in no rush to actually buy Lithium batteries. I just want the coach to be ready when / if new batteries fall in my lap. Maybe someone comes out with a way for me to get 300 or 400amps of Lithium in same space under steps or maybe even near buy.

[Morich]

It sounds like you are well into planning for futre potential changes and that is the best way I've found to go into new stuff.
I've not gone into much study on the issues as it never became something we deemed worth the study for our personal use.
Life is a series of changes and about the time we got stocked on the knowledge to do one thing, we were often changing to something else! We did the camping without the nice things like electricity and running water, gradually worked into easier but more complex camping and now just do not like to work enough to provide our own when we can just go where it is provided!

Sometimes we like to have homemade biscuits but sometimes IHOP is lots easier!

[dkoldman]

Originally Posted by Morich

It sounds like you are well into planning for futre potential changes and that is the best way I've found to go into new stuff.
I've not gone into much study on the issues as it never became something we deemed worth the study for our personal use.
Life is a series of changes and about the time we got stocked on the knowledge to do one thing, we were often changing to something else! We did the camping without the nice things like electricity and running water, gradually worked into easier but more complex camping and now just do not like to work enough to provide our own when we can just go where it is provided!

Sometimes we like to have homemade biscuits but sometimes IHOP is lots easier!

My homemade biscuits may be easier than iHops. I just pop them out of the store bought container and put them in a preheated oven A lot of work goes into making homemaking biscuits though, you have to drive to the store, check the dates and spray that stuff just right on the pan and the pop out delicious.

[dkoldman]

I have my new 2200 Inverter installed; so I will spend a week or so making sure it can handle loads. I have already run the Microwave 2 minutes.

I also finished the new switch on the Trombetta. I can now disable the Trombetta from connecting with the chassis battery or charging the house batteries direct from alternator as a source should I ever buy Lithium batteries.

I still have my DC to DC to go, but that will have to wait a little while longer.

[Morich]

Hah! Now I see what those vacant holes were left to do!
They really WERE thinking way in advance, right?


Looks like progress!

[dkoldman]

Originally Posted by Morich

Hah! Now I see what those vacant holes were left to do!
They really WERE thinking way in advance, right?


Looks like progress!

I have a come a long way with this RV. I remember when I 1st removed that panel, I was really frustrated with a WBGO dealer who could NOT find an issue with my steps randomly retracting. Kept blaming Kwikee and then starting charging me check out fees; so I would go away. I did

Behind that panel I found a loose pin I believe #9 in a 16 pin connector. It was the pin that supplied 12v to the steps to ensure it was safe to stay extended, but if it had a voltage drop the steps would retract to ensure safety and to not get stuck out with no power. I have slowly been conquesting every wire in that panel and the Trombetta and Relay have been my latest.

If you look closely 3 of the punchouts do not have the little plastic inserts. I guess I needed those, I would have to drill a hole in that spot (circle)

The Switch is Up meaning Trombetta can close when engine is running or if I press AUX Start. It seem counterintuitive today because I have AGM batteries, but in future if I have Lithium batteries the Switch will always be down to disable the Trombetta. But I am in a pinch and need AUX Start, I can simply flip that switch up, go inside the Cab use AUX Start like normal. When engine is running, I can simply go flip the switch back down.