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Topic: New Deka 8G8D House Batteries and New Magnum Inverter/Charger in 2004 36'U295 (Read 935 times) previous topic - next topic

New Deka 8G8D House Batteries and New Magnum Inverter/Charger in 2004 36'U295

My Prosine 2.5 finally died and my Lifeline AGM's were getting a little long in the tooth.  Before tackling this job I read the Forum for weeks.  I can't thank all of you enough for your thoughtful and detailed posts. 

Magnum MS2812 Inverter Setup Help Needed

To all that weighed in on the subject this post is definitely NOT for you!  You guys are light years ahead of me on the subject.  I'm just a wannabe mechanic trying to keep my coach updated and on the road.  I'm simply posting with pictures to provide more detail as it relates to the specifics of the project for this year and model coach in the hopes of helping the next guy as much as your posts helped me.  At least they'll know what to expect when they dig in.  We are usually plugged in and light AC inverter users so I went with a Magnum 2012 Inverter/Charger, a ME BMK battery monitoring kit, and a ME ARC-50 monitor.  This met all our needs and provides me with MUCH better monitoring and control of my batteries.  It runs a coffee maker, the microwave and a hair dryer.  I just had to explain to my wife that when we're not plugged in she can't do all three at the same time!  I purchased all the Magnum components from DonRowe.com in Oregon.  No sales tax, great service and arrived in 2 or 3 days.

Opened the house battery bay on the forward wall in the main PS bay with the Joey bed and disconnected them.  Also disconnected the chassis batteries and the solar controller.  No shore power to the coach.  Tight compartment and I was surprised at how the gassing over the 7 years had accumulated corrosion on my cables.  Shined up with a bicarb bath and wire brushing.  All 3/0 cables.  Reviewed the coach 12V schematic and found the dedicated -NEG to the Prosine and a house -NEG both coming into the compartment from the top.  Also from the top was a dedicated +POS with a 350amp Class T-Fuse to the inverter and another +POS to supply the house loads.  I was able to use all the existing cables and battery lug connectors and the existing Class T Fuse.  I discarded the Prosine temp sensor and replaced it with the Magnum temp sensor.  Pulled the phone wire cord to the DS compartment holding the old Prosine inverter.  Mounted the Magnum BMK shunt to the compartment wall and then put a 2 post battery terminal on the ceiling near the entry of the existing -NEG cables and tied them both to one post.  Tied the 2nd lug of the post to the load side of the shunt with a newly made -NEG cable so I would be monitoring both the inverter and the house loads.  Finally connected the battery side of the shunt with a newly made cable to the Deka Gels -NEG battery post.  Ran the twisted pair for the BMK sense monitor along with the temp senor cord out to the DS compartment housing the old Prosine inverter.  This side was done!

Removed the old Prosine inverter and created a mounting plate of 1/4" Aluminum per the post cited above from other owners.  I was able to secure it to the metal chassis by simply reusing the Prosine mounting holes in my coach.  I used 1/4-20 fully threaded studs per instructions from other owners in the post noted above.  Then I simply hung the new Magnum on the studs and secured it with Nyloc nuts and washers along with the protective hood.  I was able to use the existing AC in and out wires per Magnum's instructions, and simply used "HOT1" as my input from the coach AC panel was only 20amps.  I wired a Blue Sea 3000HD manual ON/OFF switch to the existing +POS battery cable and made a new short +POS cable from there to the inverter.  That way if I ever left the coach stored unplugged or had to service the inverter I could completely disconnect it from the AC and DC circuits.  It has a parasitic draw of roughly 7amps/day even in the off mode energizing circuits per tech support.  Lastly I mounted the BMK sense monitor to the rear of the compartment near the DC circuit breaker panel and drew power for it from the panel itself.  I used an open circuit breaker in the panel to fuse the power to the BMK unit.  I used the existing Prosine 4 wire phone cord to the new Magnum ME ARC-50 panel in the coach replacing the Xantrex monitor that told me very little.  "Plug and play" as described by others.  Lastly I removed the instrument mounting panels from the coach and made entirely new ones out of 1/4" birch ply.  Put a little color on them, and it looks just fine by me.  I should add that I dialed down my Leece Neville alternator to 13.8V at the chassis Yellow Top Optimas which gives me a reading of 13.6V  at my house batteries.  The alternator runs through a Victron Argo FET isolator.  I'm hoping that will be a reasonable compromise as our batteries are never heavily discharged, and we limit our driving to roughly 5 hours/day.  My year alternator didn't have a cover.  It was manufactured in the last week of 2002.  There's just a plug over the adjustment screw.  I've attached a picture of the model number and the plug which has to be removed to get to the adjustment screw.  (I learned that by accident while "adjusting the plug!")  Excuse the length of this post, but with my limited experience reading your posts no detail was too much detail.  I just tried to pull everything I read from all your posts and incorporate what I learned in 1 place to assist the next person.





Mark, Monique & Steven Hachigian
2004 36U295 Build No. 6239
2011 Honda CRV 4WD
2024 Dynamax Isata 5 30fw Xplorer

Re: New Deka 8G8D House Batteries and New Magnum Inverter/Charger in 2004 36'U295

Reply #1 –
Excellent technical post!  I also tend to add "too much" detail in my postings, but I feel if people don't need the details, they can just skip over them.

I see you took Don's advice and mounted the manufacturer recommended hood above the inverter.  You can't go wrong following tech tips from Don!  He sets a high bar for the rest of us.  :thumbsup:

Good photos.  Close-up detail shots are great, but sometimes can be confusing.  The pulled back wider angle shot of your electronics bay helps the viewer get oriented and see how the components are situated.

When you talk about dialing back the alternator output, you could mention that the Victron Argo FET isolator is a (almost) zero loss design, as opposed to the older diode based isolators.  With the Victron, the input voltage from alternator is very close to the same as what goes out to the battery banks.

Excellent tip on the adjustment screw on the alternator.  Looking at your photo of the voltage regulator section, I would never guess it is adjustable.
1993 U280 SE 40' WTBI, Build: 4359
C8.3 300hp, 6-Speed, Exhaust Brake
960 watts on the roof (6 x 160)
Sorento (or BOLT) on a Kar Kaddy SS
"Nature abhors a vacuum"

Re: New Deka 8G8D House Batteries and New Magnum Inverter/Charger in 2004 36'U295

Reply #2 –
Nice job.  I just helped change a set of batteries in the cave and I know it is some work.

In years past 2001, FT ran one set of cables from the batteries directly to the inverter with a big in-line fuse in the plus cable.  The also ran one set of cables from the batteries to the 12v distribution lugs behind the white fiberglass panel (yours may have been covered with gray carpet).  Adding the 2 post bus bar so that all of the negative loads go through the shunt was a good choice, something that is overlooked sometimes.

You might want to consider adding a big switch on the negative cable between the batteries and the shunt or the shunt and the 2 post bus bar.  This makes it easy to disconnect power to the coach and the inverter when you want to or need to.  Easier than removing a cable if time is critical.
Roger Engdahl and Susan Green
2001 U320 3610 #5879 (Home2) - 2014 Jeep Cherokee or 2018 F150
Hastings, MN

Re: New Deka 8G8D House Batteries and New Magnum Inverter/Charger in 2004 36'U295

Reply #3 –
Thanks for the picture of the alternator adjustment plug. I know how to adjust my alternator now.
Peter and Frieda Morin
1999 36ft. U320 Foretravel
Build # 5436
1998 Suzuki Sidekick Sport

Re: New Deka 8G8D House Batteries and New Magnum Inverter/Charger in 2004 36'U295

Reply #4 –
Unless you change battery technology, you may not need to adjust the regulator.

Said another way, changing from a diode-based isolator to either a marine ON-OFF switch or new generation isolator with minimal voltage loss, no change is needed.  The "sense wire" is connected to the chassis battery side of the isolator.  So, if diode-based isolator, it tells the alternator/regulator that it must output an additional .7 VDC which is then lost in the diode-based isolator.  With either a switch or low-loss isolator, the alternator just puts out the correct voltage.
Brett Wolfe
EX: 1993 U240
Moderator, ForeForum 2001-
Moderator Diesel RV Club 2002-
Moderator, FMCA Forum 2009-2020
Chairman FMCA Technical Advisory Committee 2011-2020

Re: New Deka 8G8D House Batteries and New Magnum Inverter/Charger in 2004 36'U295

Reply #5 –
Batteries are Deka? Not Lifeline?
Where did you get them? AGM or Lithium?
Glenn and Amy Beinfest
2001 36' U320
#5812
2014 Honda CRV

No Whining on the YACHT

Re: New Deka 8G8D House Batteries and New Magnum Inverter/Charger in 2004 36'U295

Reply #6 –
I changed from Lifeline AGM batteries to Deka Gel batteries.  I did that because of the gassing effects that I noticed in the battery compartment.  The gels ought not gas.  As Brett indicated I down regulated my alternator because of the different charge profiles between AGM and GEL per the manufacturers and the gassing that I noticed given our use.  I'm in Southern California and most if not all the GELs here come from East Penn Manufacturing through a single distributor.  I actually met him while searching for a retailer myself.  They place 3 or 4 different brand labels on them.  Most retail suppliers of batteries can get them within a week.  Prices ranged from $700 to $850 per battery.  They did provide a $150 core refund for my 3 AGMs. 

I will add that I'm really pleased with the balance and function of my house electrical system.  Batteries go down and within a couple of hours batteries go up.  I can monitor DC house loads down to individual LED light bulbs.  In fact when I was leaving the coach one evening I noticed a 3 or 4 amp draw, and after searching found that I left a bay light on that went unnoticed.

The one thing I would like to hear about from those more knowledgeable is what do I do if I have to replace the Leece Neville with an internally regulated Delco Remy at 14V?     
Mark, Monique & Steven Hachigian
2004 36U295 Build No. 6239
2011 Honda CRV 4WD
2024 Dynamax Isata 5 30fw Xplorer

Re: New Deka 8G8D House Batteries and New Magnum Inverter/Charger in 2004 36'U295

Reply #7 –
There is a pretty simple MANUAL, repeat MANUAL solution to overcharging the house batteries while driving all day.

Merely connect the house bank through a simple marine ON-OFF switch. An easy location is at the foot of the bed (near the battery isolator).  With switch OFF, only the chassis battery is charged.  With switch on both banks are charged.

Yes, it can even replace the battery isolator.  Alternator B+ and chassis battery to one side of switch and house bank to the other. That is exactly what  I did-- just did not make sense to use diesel to over-work the alternator to over-charge the house bank if driving all day.

Has appeal to those of us KISS theory guys.
Brett Wolfe
EX: 1993 U240
Moderator, ForeForum 2001-
Moderator Diesel RV Club 2002-
Moderator, FMCA Forum 2009-2020
Chairman FMCA Technical Advisory Committee 2011-2020

Re: New Deka 8G8D House Batteries and New Magnum Inverter/Charger in 2004 36'U295

Reply #8 –
Quote from: Hach –
The one thing I would like to hear about from those more knowledgeable is what do I do if I have to replace the Leece Neville with an internally regulated Delco Remy at 14V?
I'm not among the "more knowledgeable" but I am a proficient Googler.  Searched "external voltage regulator for 12 volt gel batteries".  One hit below sounded promising:

Balmar Voltage Regulation Technology - BalmarBalmar
1993 U280 SE 40' WTBI, Build: 4359
C8.3 300hp, 6-Speed, Exhaust Brake
960 watts on the roof (6 x 160)
Sorento (or BOLT) on a Kar Kaddy SS
"Nature abhors a vacuum"

Re: New Deka 8G8D House Batteries and New Magnum Inverter/Charger in 2004 36'U295

Reply #9 –
Quote from: Chuck & Jeannie –
I'm not among the "more knowledgeable" but I am a proficient Googler.  Searched "external voltage regulator for 12 volt gel cells".  One hit below sounded promising:

Balmar Voltage Regulation Technology - BalmarBalmar

Yup, used one of those on the sail boat's high output alternator-- basically turns your alternator into a "smart charger". And just like with a smart charger, you can tailor it to your particular battery technology.
Brett Wolfe
EX: 1993 U240
Moderator, ForeForum 2001-
Moderator Diesel RV Club 2002-
Moderator, FMCA Forum 2009-2020
Chairman FMCA Technical Advisory Committee 2011-2020

Re: New Deka 8G8D House Batteries and New Magnum Inverter/Charger in 2004 36'U295

Reply #10 –
Thank you for your suggestions.  I really like the KISS approach and a manual switch at the foot of the bed will be perfect for our usage while driving.  It's so great to get other opinions to open up my thinking.  I was tunnel vision on the external regulator solution, but the switch works great for our purposes and is less complex.  I'll just put a switch between the isolator and the house battery bank.  I am partial to upgrading the OEM components but not re-engineering the entire electrical system.  I understand that other do better with new systems, but my wife is more into glamping than off grid camping.  Happy wife happy life!  Thank you so much.
Mark, Monique & Steven Hachigian
2004 36U295 Build No. 6239
2011 Honda CRV 4WD
2024 Dynamax Isata 5 30fw Xplorer