Inverter

[Batmobile]

Does anyone have this inverter? How do we know if it's a PSW or MSW? Reading about power for our new Fisher-Pakel residential fridge and might need to upgrade as we don't want to damage the electriconics in our $3500 fridge!

[fiat124man]

Looks like a MSW inverter. What year is coach ?

[Batmobile]

2001 36' Monaco Diplomat 

[JDCrow]

Anyone really know if Mod-sine inverters really put the hurt on newer electronics? 
 

Make no mistake, I’m not taking any chances and my new Victron Multiplus 2 came in last week, but I just “hear” Mod-Sine are bad. Any real world experience? 

Edited June 13, 2021 by JDCrow

[Dr4Film]

JD,

Yes, there are some electronics that really don't like MSW power. Luckily I have only found one device that I attempted to use that did not play nicely with my MSW Inverter. That was a 120 VAC remote power switch that I use to turn on the swag lamp I installed over our dinette table as Monaco decided not to put one in our Windsor. After destroying one already, I ordered an updated one and I now keep it plugged into a non-inverter driven duplex.

There are people who have burned up electric blankets, clocks, coffee pots, and other devices while using a MSW Inverter.

57 minutes ago, Batmobile said:

Does anyone have this inverter? How do we know if it's a PSW or MSW? Reading about power for our new Fisher-Pakel residential fridge and might need to upgrade as we don't want to damage the electriconics in our $3500 fridge!

The Fisher-Paykel works great on MSW power as reported by others who have installed them. Do a search here to see what others have said. Also do a Google search to see what you can find on the Internet.

Also, here is a copy of the Trace Legend Inverter in case you don't have one.

http://www.xantrex.com/documents/Discontinued-Products/3178UX-L-TRevNew.pdf

[jacwjames]

Here is a link to the brochure for the Trace Legend 1,  it is a MSW inverter.

http://static6.arrow.com/aropdfconversion/6dfa35d9217e1772ead3d2a6366ea8ec80646b2b/legendi.pdf

The Fisher Paykal is known to work with the MSW inverters.  This has been a popular choice for people to upgrade to, although a bit pricey. 

[Ivan K]

We destroyed a brand new fancy coffee maker while running it on inverter.  Realized the mistake and now use a simple one with no fancy electronics that we never cared for anyway. 

[Batmobile]

1 hour ago, Dr4Film said:

JD,

Yes, there are some electronics that really don't like MSW power. Luckily I have only found one device that I attempted to use that did not play nicely with my MSW Inverter. That was a 120 VAC remote power switch that I use to turn on the swag lamp I installed over our dinette table as Monaco decided not to put one in our Windsor. After destroying one already, I ordered an updated one and I now keep it plugged into a non-inverter driven duplex.

There are people who have burned up electric blankets, clocks, coffee pots, and other devices while using a MSW Inverter.

The Fisher-Paykel works great on MSW power as reported by others who have installed them. Do a search here to see what others have said. Also do a Google search to see what you can find on the Internet.

Also, here is a copy of the Trace Legend Inverter in case you don't have one.

http://www.xantrex.com/documents/Discontinued-Products/3178UX-L-TRevNew.pdf

Thanks for the link! We may decide to add a PSW inverter just for the fridge to be on the safe side.

1 hour ago, jacwjames said:

Here is a link to the brochure for the Trace Legend 1,  it is a MSW inverter.

http://static6.arrow.com/aropdfconversion/6dfa35d9217e1772ead3d2a6366ea8ec80646b2b/legendi.pdf

The Fisher Paykal is known to work with the MSW inverters.  This has been a popular choice for people to upgrade to, although a bit pricey. 

Yes, the Fisher-Pakel is pricey but it's the only one that will fit the hole. Yes, could have converted Norcold but so many people threw good money after bad that we decided this was best for us in the long run.

13 minutes ago, Ivan K said:

We destroyed a brand new fancy coffee maker while running it on inverter.  Realized the mistake and now use a simple one with no fancy electronics that we never cared for anyway. 

That sucks about your coffee maker! What kind was it? We have a nespresso and never gave the power a thought!

Yeah, it's the fancy electronics in this fridge that I just don't want to mess with.

Edited June 13, 2021 by Batmobile

[waterskier_1]

It seems that certain devices are more sensitive than others.  Any device that uses a "wall wart" to take 120 VAC to some other X VDC (where X = 5, 9, 12, 18, 24, etc.) work fine since any ac is converted to DC before the device sees it.  Over the years, it seems high end coffee makers (Keurig specifically) and electric blankets/throws with digital readout controls seem to be the biggest problems.  The only manufacture doing business in the USA (as of a few years ago) that warranties their refrigerator for operation on MSW inverters is Samsung.  That's why so many are using it even with all the problems (recalls, class-action suits, etc.) they have against them.  That isn't to say that they are the only ones to make a refrigerator that will operate on MSW, but rather that they are the only manufacturer to incur the cost and time testing their refrigerator so they know it will not be affected by MSW.  As you may imagine, using inverters to power residential refrigerators is a very small portion of the potential consumers.  I personally haven't heard of a single refrigerator failure due solely to being operated on MWS.  But I have read many warranties that won't cover their refrigerators operating in a mobile environment.  Look at what the coach manufacturers are installing.  I don't think all new coaches come with PSW inverters, but the ones with residential refrigerators might?

  

[Ivan K]

3 hours ago, Batmobile said:

 

That sucks about your coffee maker! What kind wkas it? We have a nespresso and never gave the power a thought!

Yeah, it's the fancy electronics in this fridge that I just don't want to mess with.

I'm sorry but I do not know or remember the make, it was a Christmas present and had too many buttons and options that I did not get to know. And I wasn't gonna carry it with us for 4 months when our trip just started in February. I opened it and found a burned circuit board before it went to trash in Quartzsite. I know there was no transformer and I assumed that the voltage conversion down to the chip level was the problem with MSW. Our current coffeemaker has one switch and makes 12 cups, all we need...

[Mark B]

I just finished my electrical system upgrade. A little spendy but I now have the system I want.

Replaced the Xantrex RV2012 with a new Xantrex SW3012 and controller with auto gen start.

Replaced the old IOTA transfer switch to a WFCO ATS.

Added a Southwire Surge Guard hardwired in with the remote monitor.

Replaced the solar controller with a Victron 100/50 mppt, 200 watts on the roof expandable to 700.

Added a Victron BMV-712 battery monitor, redundant to the inverter controller but it has bluetooth and is networked with the solar controller. I located the shunt in a spot under the main fuse. 

Pulled network cable from the back to the front, ran it up the passenger side A pillar into the control cabinet. This was by far the hardest part of the project. Cables for the battery monitor, surge protector and inverter controller.

Up-sized the wire on the positive side from the battery box to the disconnect, to the fuse, and out to the inverter line. All the negative and positive run to the inverter were already 4/0.

Finally replaced my dead 4-6 volt house batteries with 2 100 amp hour Battleborn batteries.

This project was completed over a five month period with four trips in between. We are going to spend some time off grid to test it all next week on our way to Bishop Ca. Going to stop at Alabama Hills in Lone Pine for a couple of nights.

I'd be glad to answer any question about my setup.

[JDCrow]

7 hours ago, Mark B said:

I just finished my electrical system upgrade. A little spendy but I now have the system I want.

Replaced the Xantrex RV2012 with a new Xantrex SW3012 and controller with auto gen start.

Replaced the old IOTA transfer switch to a WFCO ATS.

Added a Southwire Surge Guard hardwired in with the remote monitor.

Replaced the solar controller with a Victron 100/50 mppt, 200 watts on the roof expandable to 700.

Added a Victron BMV-712 battery monitor, redundant to the inverter controller but it has bluetooth and is networked with the solar controller. I located the shunt in a spot under the main fuse. 

Pulled network cable from the back to the front, ran it up the passenger side A pillar into the control cabinet. This was by far the hardest part of the project. Cables for the battery monitor, surge protector and inverter controller.

Up-sized the wire on the positive side from the battery box to the disconnect, to the fuse, and out to the inverter line. All the negative and positive run to the inverter were already 4/0.

Finally replaced my dead 4-6 volt house batteries with 2 100 amp hour Battleborn batteries.

This project was completed over a five month period with four trips in between. We are going to spend some time off grid to test it all next week on our way to Bishop Ca. Going to stop at Alabama Hills in Lone Pine for a couple of nights.

I'd be glad to answer any question about my setup.

I’m going to go down the same road. A few questions:

1) it looks like you held on to your combiner solenoid? 
 

2) Do you have a DC/DC charger to charge the lithium from your alternator?

3) Did your shore power go into your breaker panel, and then have a 30 am breaker coming back down to the inverter? Mine does and the inverter essentially powers the microwave and 1 circuit in the coach. I need to pull it all down as the the new inverter is pass through and boost. 
 

Thanks in advance, I’m trying to learn as much as I can. I tackled this a bit on my 5ver, but only has “coach” batteries and not chassis. Obviously. I did run 2 banks, 1 just for res fridge and a bigger one for rest if 5ver with a switch to add the 2nd bank to refer bank if needed. 
 

 

[Mark B]

8 hours ago, JDCrow said:

I’m going to go down the same road. A few questions:

1) it looks like you held on to your combiner solenoid? 
 

2) Do you have a DC/DC charger to charge the lithium from your alternator?

3) Did your shore power go into your breaker panel, and then have a 30 am breaker coming back down to the inverter? Mine does and the inverter essentially powers the microwave and 1 circuit in the coach. I need to pull it all down as the the new inverter is pass through and boost. 
 

Thanks in advance, I’m trying to learn as much as I can. I tackled this a bit on my 5ver, but only has “coach” batteries and not chassis. Obviously. I did run 2 banks, 1 just for res fridge and a bigger one for rest if 5ver with a switch to add the 2nd bank to refer bank if needed. 
 

 

JDCrow, I too had a 5ver before upgrading to this coach.

1) I left the combiner as it shouldn't make a difference as the charging is controlled by the bidirectional relay and the combiner is for emergency starting.

2) In my previous rig I did had a Renogy DC to DC charger with 1/0 wire coming from the truck but not needed in this configuration. If I need to recharge the batteries I will run the generator. The main advantage of the lithium is how fast it can be charged. At this point I'm not worried about the alternator getting over worked charging the batteries as the isolation charge relay should control the charge rate.

3) Shore power goes to the transfer switch first. The to the main distribution panel and EMS. There are two circuits in my coach that go to the inverter, that is why I chose the Xantrex SW3012. Looking back I could have chosen the Victron Quatro or the Multiplus 2. Most of the outlets in my coach run off of the inverter, not on the inverter are the AC's front and back, washer/dryer, Block heater and water heater. There are two outlets behind the refrigerator, one for the refer and one for the ice maker.  I have my refrigerator plugged into the ice maker plug as it's on the inverter, the other is not. This is so I can have the propane off while driving and run the refrigerator off the inverter.

If you don't have the circuits set up like mine you can run the entire system off of the inverter using the Victron Quatro or the Multiplus 2. Both can pass through a 50 amp service. There is additional work that needs to be done with regards to circuit protection and operation. I didn't need to go that route and having a professional set it up can be very expensive. I have about $4500 in all my upgrades, I could have spent way more and I did all the work myself. I have extensive background in electrical and telemetry working in the wastewater industry for 33 years. Check out the Drycamper on youtube, he's shows his builds to see whats possible but he doesn't to diy tutorials. Good luck

[waterskier_1]

45 minutes ago, Mark B said:

JDCrow, I too had a 5ver before upgrading to this coach.

1) I left the combiner as it shouldn't make a difference as the charging is controlled by the bidirectional relay and the combiner is for emergency starting.

2) In my previous rig I did had a Renogy DC to DC charger with 1/0 wire coming from the truck but not needed in this configuration. If I need to recharge the batteries I will run the generator. The main advantage of the lithium is how fast it can be charged. At this point I'm not worried about the alternator getting over worked charging the batteries as the isolation charge relay should control the charge rate.

3) Shore power goes to the transfer switch first. The to the main distribution panel and EMS. There are two circuits in my coach that go to the inverter, that is why I chose the Xantrex SW3012. Looking back I could have chosen the Victron Quatro or the Multiplus 2. Most of the outlets in my coach run off of the inverter, not on the inverter are the AC's front and back, washer/dryer, Block heater and water heater. There are two outlets behind the refrigerator, one for the refer and one for the ice maker.  I have my refrigerator plugged into the ice maker plug as it's on the inverter, the other is not. This is so I can have the propane off while driving and run the refrigerator off the inverter.

If you don't have the circuits set up like mine you can run the entire system off of the inverter using the Victron Quatro or the Multiplus 2. Both can pass through a 50 amp service. There is additional work that needs to be done with regards to circuit protection and operation. I didn't need to go that route and having a professional set it up can be very expensive. I have about $4500 in all my upgrades, I could have spent way more and I did all the work myself. I have extensive background in electrical and telemetry working in the wastewater industry for 33 years. Check out the Drycamper on youtube, he's shows his builds to see whats possible but he doesn't to diy tutorials. Good luck

1. How do you expect a relay to control charging current (or voltage)?  All the BIRD or IRD in lower level coaches does is supply a signal (voltage) to the Big Boy Solenoid (Relay - what I think you are calling "combiner") that connects both battery banks together as one huge bank.  Granted it only connects when there is a charging source, but that is all it does.  It can not control current (other than burning up) or voltage.  The voltage when the alternator is running should be around 14.2 - 14.4 volts.  That's way to high to apply to lithium batteries for a 6 - 8 hour drive.  I think BattleBorn recommends 30 minutes per 100A-Hr then drop to down to 13.4 Volts.  That's why people are so concerned about using the engine alternator to charge lithium batteries.  Another concern is the extremely low internal resistance which means that it will accept charge current much faster (up to 10X as fast) and if not controlled, will easily overtask the alternator.

2)  Not clear what you are saying.  You say if you need to charge the batteries, you'll run the generator, but then you talk again about not worrying about the alternator being over worked.  

3) It sounds like you are not able to take advantage of the extra 1000 Watts in the Inverter you purchased.  This is a common problem people have.  I've helped many design "after the fact" electrical wiring systems because of this problem.  You are not alone.

For someone considering this, here are some things to consider.  As Mark B. mentioned, all the circuits that you want to run off the inverter must run through the inverter, even when it is on shore power.  That means that what you have connected now is all that will be connected when you replace the inverter - typically this is the microwave and a string of outlets.  The outlets will be limited to 20 Amp (in some cases 30A) maximum, not mater what inverter you install, unless you rewire the coach.  This is because the existing wiring will only handle the 20 Amps.  This is not impossible to overcome, a simple Inverter Sub-Panel will do the job, but you'll still need to run new wires to it, from the new loads, or separate the outlets into more than one string so you can have 20 Amps on each string.  Magnum allows for connecting their inverter/charger to the incoming AC panel with 30 Amp breaker (which is what most have in place) and the associated wiring.  What they don't tell you is that if you choose to do this, and want to use the full 3000 watts, you can NOT charge your batteries at the same time.  Victron uses a 50 Amp Breaker in the AC Panel, along with requiring larger wires to connect the inverter, such that you can use the full 125 Amp battery charger at the same time as drawing a 3000 watt load.  Just something to consider.  Most Dynasty and above coaches already have an Inverter Subpanel, so little additional wiring is required.

On the DC side there are two concerns.  First, no matter which battery type you choose, you'll likely need to increase the cables connecting the batteries to the inverter since you'll now be drawing 50% (3000 vs 2000 watts) more power and the cable must carry the extra current.  This is something often overlooked.  In some installations, the inverter is very close to the batteries (less than 5-ft cable) which wouldn't likely require an upgrad.  But if your inverter is 15-25 ft (cable length) away, it likely will require upgrading.

Now the big monkey in the box:  Adding Lithium Batteries.  First, this is likely the reason that the invert is being replaced.  It likely doesn't have charge parameters for Lithium Charing Profiles.  Some are replacing because they want Pure Sine Wave.  Some think they need more "power".  But for this portion of discussion, lets assume the inverter/charger has the requisite Lithium Charge Profile.  That's good.  But only when charging from the inverter/charger (meaning on shore power or generator).  Also, the lithium charge profile is not ideal for lead acid batteries, which you likely still have for Chassis Batteries.  So, that means it is best not to allow the inverter/charger to charge the chassis batteries (or install some sort of controller between the two).  The other concern I eluded to above is charging the lithium batteries from the alternator.  Lithium batteries do not like an "absorption" charge for long periods of time.  They also do not like to be stored fully charged.  Yes, you can do that, but it will significantly decrease battery life.  So, what to do.  There are some work-arounds out there that in my opinion are not ready for prime time.  Battleborn markets one such unit that allows the alternator to charge the lithium batteries for a preset amount of time (13 Minutes?) and then disconnects them for 20 minutes.  Talking with the manufacturer, this is done more to keep the alternator from overheating and burning up than controlling the charge voltage of the Lithium batteries.  DC-DC converts are a much better choice.  What we see is that trying to charge Lithium and Lead Acid batteries with the charger is less than ideal.  

I explored all this and even though I don't have Lithium batteries (yet) because of the environment I store my coach (below -10 for days, several time a year) I still didn't like the mixed charging of my Lifeline AGM batteries.  Therefore, I modified the Big Boy and basically disconnected the BIRD.  Now the only way to energize the Big Boy (and connect the chassis and house batteries together) is with the BATT BOOST switch on the dash.  I can restore it to original configuration with swapping a couple wire.  This means that my alternator only charges the chassis batteries, never the house batteries; and my inverter/charger charges only my house batteries, never my chassis battery.  This work for me because I also have 1400 watts of solar on the roof.  The original 100 Watt panel is now dedicated to only the chassis battery.  The remaining 1300 Watts is dedicated to only the house battery.  This way I can set the ideal charge profile for each battery bank (including solar charge profiles). I did this primarily because with the solar charging I really didn't want my AGM house batteries setting with 14.2 volts on them for 8 hours going down the road, when they were already fully charged by the solar and should be in float mode.  I don't worry about my alternator overheating or burning up charging my house batteries (not like with AGMs, but more likely with Lithium).  This works for me, but might not work for others.  BTW, I see no advantage to having Lithium batteries if you don't have solar to charge them.  Sure they may last longer, weigh less, charge faster, but remember, for every bit of energy you take out of them, you have to replace at some point.  This might mean that instead of running your generator a couple hours every day to charge you non-Lithium batteries, you can go two or three days, and then run your generator 4 -8 hours to recharge them.  Happy to answer any questions.  Much better to ask ahead than after and have to expend more funds than you realized for marginal improvement.

  -Rick N.

[Mark B]

Thanks for the advise Rick. How do I disconnect the BIRD or is just disconnecting the house from the isolation relay or "maintainer" enough (not the big boy)? Or is the BIRD controlling another relay? I know Battleborn sells the lithium BIM but I didn't think I needed it.

Edited June 15, 2021 by Mark B

[waterskier_1]

27 minutes ago, Mark B said:

Thanks for the advise Rick. How do I disconnect the BIRD or is just disconnecting the house from the isolation relay or "maintainer" enough (not the big boy)? Or is the BIRD controlling another relay? I know Battleborn sells the lithium BIM but I didn't think I needed it.

I'm trying to make sense of this.  It appears that you have a BIRD (Bi-Directional Isolator Relay Delay) but it appears there is another isolator, which I'm not sure of it's purpose.  The BIRD does control another Relay - The Big Boy.  The way the BIRD works, in general, is that when the ignition switch is turned on, it signals the BIRD to start a Delay.  After that Delay (which is intended to allow the engine to come up to speed and get the alternator running) the BIRD signals the Isolator Relay (which many call "The Big Boy") to energize.  It is the Big Boy that actually connects the two battery banks together.  There is more that goes on in the BIRD.  It must sense that one battery bank is over 13.5 volts before it will allow connection.  This function is to make sure that at least one of the banks is actually being charged (and no bad, unchargable batteries) before allow the banks to be connected.  The basic IRD only looks at the chassis battery, and therefore only allows connecting the banks together when the chassis battery is being charged (the engine is running and the alternator is working).  The BIRD goes a step further.  It also looks at the House Batteries, and if they are over 13.5 volts, it will signal the Big Boy to connect.  This allow you to charge the chassis battery while on shore (or gen) power.  

Ok, now back to the basic question.  The easiest way to handle this is to simply disconnect the purple wire which provides the power to turn on the Big Boy.  Without that wire, the BIRD will not engage the Big Boy.  Depending on how it is wired - I'm not sure about yours, many have a separate (usually RED) wire from the BAT BOOST switch to the Big Boy.  If that is your case, then you'll still be able to connect the two banks together with that switch.  Otherwise, you'll have to reconnect the purple wire, or simply jump the two banks together.  

Not that I do not know what that other isolator is doing.  I don't have any wiring diagrams showing it, so I'm not sure how that might affect what I've described above.  Do you know it's purpose?  From the size of the wires, it's not got much of a load.

 

[Mark B]

Rick, the purple wire goes to the big boy relay. The "maintainer" is a trickle charger I believe, wire goes to the chassis battery side of the big boy. I will do some testing to see. The drawing isn't very clear. I can follow the big boy trigger wires from the boost switch and the BIRD. Thanks again for saving possible future problems.

[Dr4Film]

Mark, the BIRD that is in our 2002 Windsor's is really wired to act like an IRD versus an actual BIRD.

I have attached a hand drawn schematic of the wiring of our BIRD's.

I mis-marked the BIRD as a BIRD-2 which it is not. Just overlook that minor detail.

Hope this drawing helps you to understand how it is wired and the function it performs.

BTW, our Battery Isolator Relay is not a Big Boy as it is a White Rogers Relay Solenoid.

BIRD Diesel Schematic.pdf

[jacwjames]

Mark,

FYI, there is a wiring diagram in the Downloads for 2002 Windsor.  It has a bunch of schematics for the entire coach including the schematic you attached.  It is a PDF file and on this page, when you open the file, it will be bluffy, hit CTRL5 and it clears right up.  I've actually zoom in and then print current view on areas I'm looking at.  I can also add sticky notes to add information.   Attached is one for the passenger side rear bay.

I also just submitted a chassis wiring diagram for a 2002 Windsor

2002_Windsor_wiring_passenger side 12 volt.pdf

[waterskier_1]

12 minutes ago, Dr4Film said:

Mark, the BIRD that is in our 2002 Windsor's is really wired to act like an IRD versus an actual BIRD.

I have attached a hand drawn schematic of the wiring of our BIRD's.

I mis-marked the BIRD as a BIRD-2 which it is not. Just overlook that minor detail.

Hope this drawing helps you to understand how it is wired and the function it performs.

BTW, our Battery Isolator Relay is not a Big Boy as it is a White Rogers Relay Solenoid.

BIRD Diesel Schematic.pdf 1.14 MB · 1 download

Richard, do you know the purpose of having the wire to the generator?  If it's only an IRD, how does the generator play in this scenario? 

[waterskier_1]

7 minutes ago, jacwjames said:

Mark,

FYI, there is a wiring diagram in the Downloads for 2002 Windsor.  It has a bunch of schematics for the entire coach including the schematic you attached.  It is a PDF file and on this page, when you open the file, it will be bluffy, hit CTRL5 and it clears right up.  I've actually zoom in and then print current view on areas I'm looking at.  I can also add sticky notes to add information.   Attached is one for the passenger side rear bay.

I also just submitted a chassis wiring diagram for a 2002 Windsor

2002_Windsor_wiring_passenger side 12 volt.pdf 117.09 kB · 1 download

Jim, thanks for the CTRL5 hint.  Why didn't I ever hear that before!  I now see that the gen signal is to lock out the Isolator Relay if both the alternator and genset - inverter/charger are both operational. That would solve the ALT-FAIL light when both are charging.  I still am not clear why Monaco would use a BIRD, as an IRD, and then add what looks like a Lampert Battery Maintainer.  That device has proven to be problematic.  

[Dr4Film]

32 minutes ago, waterskier_1 said:

Richard, do you know the purpose of having the wire to the generator?  If it's only an IRD, how does the generator play in this scenario? 

Rick, there is a Battery Maintainer Lockout Relay that is used when the Generator and engine are both running.

[jacwjames]

18 minutes ago, waterskier_1 said:

Jim, thanks for the CTRL5 hint.  Why didn't I ever hear that before!  I now see that the gen signal is to lock out the Isolator Relay if both the alternator and genset - inverter/charger are both operational. That would solve the ALT-FAIL light when both are charging.  I still am not clear why Monaco would use a BIRD, as an IRD, and then add what looks like a Lampert Battery Maintainer.  That device has proven to be problematic.  

I was having issues with my maintainer keeping my chassis battery charged.  In the past I never heard it clicking but about a month ago it started clicking sometimes for days on end.  Checked everything multiple times.  Finally threw in the towel and installed a Blue Sea ML-ACR which replaces the BIRD, Isolation Relay, and Battery Maintainer. 

[Mark B]

Thank you everyone for your input. Way more going on in this coach than my previous 5ver. I have a much better understanding of the interaction of the chassis and house battery system.

[JDCrow]

19 hours ago, waterskier_1 said:

1. How do you expect a relay to control charging current (or voltage)?  All the BIRD or IRD in lower level coaches does is supply a signal (voltage) to the Big Boy Solenoid (Relay - what I think you are calling "combiner") that connects both battery banks together as one huge bank.  Granted it only connects when there is a charging source, but that is all it does.  It can not control current (other than burning up) or voltage.  The voltage when the alternator is running should be around 14.2 - 14.4 volts.  That's way to high to apply to lithium batteries for a 6 - 8 hour drive.  I think BattleBorn recommends 30 minutes per 100A-Hr then drop to down to 13.4 Volts.  That's why people are so concerned about using the engine alternator to charge lithium batteries.  Another concern is the extremely low internal resistance which means that it will accept charge current much faster (up to 10X as fast) and if not controlled, will easily overtask the alternator.

2)  Not clear what you are saying.  You say if you need to charge the batteries, you'll run the generator, but then you talk again about not worrying about the alternator being over worked.  

3) It sounds like you are not able to take advantage of the extra 1000 Watts in the Inverter you purchased.  This is a common problem people have.  I've helped many design "after the fact" electrical wiring systems because of this problem.  You are not alone.

For someone considering this, here are some things to consider.  As Mark B. mentioned, all the circuits that you want to run off the inverter must run through the inverter, even when it is on shore power.  That means that what you have connected now is all that will be connected when you replace the inverter - typically this is the microwave and a string of outlets.  The outlets will be limited to 20 Amp (in some cases 30A) maximum, not mater what inverter you install, unless you rewire the coach.  This is because the existing wiring will only handle the 20 Amps.  This is not impossible to overcome, a simple Inverter Sub-Panel will do the job, but you'll still need to run new wires to it, from the new loads, or separate the outlets into more than one string so you can have 20 Amps on each string.  Magnum allows for connecting their inverter/charger to the incoming AC panel with 30 Amp breaker (which is what most have in place) and the associated wiring.  What they don't tell you is that if you choose to do this, and want to use the full 3000 watts, you can NOT charge your batteries at the same time.  Victron uses a 50 Amp Breaker in the AC Panel, along with requiring larger wires to connect the inverter, such that you can use the full 125 Amp battery charger at the same time as drawing a 3000 watt load.  Just something to consider.  Most Dynasty and above coaches already have an Inverter Subpanel, so little additional wiring is required.

On the DC side there are two concerns.  First, no matter which battery type you choose, you'll likely need to increase the cables connecting the batteries to the inverter since you'll now be drawing 50% (3000 vs 2000 watts) more power and the cable must carry the extra current.  This is something often overlooked.  In some installations, the inverter is very close to the batteries (less than 5-ft cable) which wouldn't likely require an upgrad.  But if your inverter is 15-25 ft (cable length) away, it likely will require upgrading.

Now the big monkey in the box:  Adding Lithium Batteries.  First, this is likely the reason that the invert is being replaced.  It likely doesn't have charge parameters for Lithium Charing Profiles.  Some are replacing because they want Pure Sine Wave.  Some think they need more "power".  But for this portion of discussion, lets assume the inverter/charger has the requisite Lithium Charge Profile.  That's good.  But only when charging from the inverter/charger (meaning on shore power or generator).  Also, the lithium charge profile is not ideal for lead acid batteries, which you likely still have for Chassis Batteries.  So, that means it is best not to allow the inverter/charger to charge the chassis batteries (or install some sort of controller between the two).  The other concern I eluded to above is charging the lithium batteries from the alternator.  Lithium batteries do not like an "absorption" charge for long periods of time.  They also do not like to be stored fully charged.  Yes, you can do that, but it will significantly decrease battery life.  So, what to do.  There are some work-arounds out there that in my opinion are not ready for prime time.  Battleborn markets one such unit that allows the alternator to charge the lithium batteries for a preset amount of time (13 Minutes?) and then disconnects them for 20 minutes.  Talking with the manufacturer, this is done more to keep the alternator from overheating and burning up than controlling the charge voltage of the Lithium batteries.  DC-DC converts are a much better choice.  What we see is that trying to charge Lithium and Lead Acid batteries with the charger is less than ideal.  

I explored all this and even though I don't have Lithium batteries (yet) because of the environment I store my coach (below -10 for days, several time a year) I still didn't like the mixed charging of my Lifeline AGM batteries.  Therefore, I modified the Big Boy and basically disconnected the BIRD.  Now the only way to energize the Big Boy (and connect the chassis and house batteries together) is with the BATT BOOST switch on the dash.  I can restore it to original configuration with swapping a couple wire.  This means that my alternator only charges the chassis batteries, never the house batteries; and my inverter/charger charges only my house batteries, never my chassis battery.  This work for me because I also have 1400 watts of solar on the roof.  The original 100 Watt panel is now dedicated to only the chassis battery.  The remaining 1300 Watts is dedicated to only the house battery.  This way I can set the ideal charge profile for each battery bank (including solar charge profiles). I did this primarily because with the solar charging I really didn't want my AGM house batteries setting with 14.2 volts on them for 8 hours going down the road, when they were already fully charged by the solar and should be in float mode.  I don't worry about my alternator overheating or burning up charging my house batteries (not like with AGMs, but more likely with Lithium).  This works for me, but might not work for others.  BTW, I see no advantage to having Lithium batteries if you don't have solar to charge them.  Sure they may last longer, weigh less, charge faster, but remember, for every bit of energy you take out of them, you have to replace at some point.  This might mean that instead of running your generator a couple hours every day to charge you non-Lithium batteries, you can go two or three days, and then run your generator 4 -8 hours to recharge them.  Happy to answer any questions.  Much better to ask ahead than after and have to expend more funds than you realized for marginal improvement.

  -Rick N.

I’m looking at Chins “smart” lithium. I believe Battle Born is coming out with their version. The smart lithium has and internal heater that kicks on with Lower temps and allows them to be charged below freezing.

 

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