MAGNUM ENERGY Smart Battery Combiner

[sdennislee]

MAGNUM ENERGY Smart Battery Combiner at West Marine

House and chassis batteries both charge off alternator when running. When using shore power only the house batteries charge. At least thats my assumption based on the following tests with multimeter:

Shore power disconnected, engine off - house and chassis batteries 12.77 V
Engine running - house and chassis batteries 14.44 V
Shore power on, engine off - house batteries 14.44 V chassis batteries 12.77 V

I have the Magnum MS2012 Inverter/Charger in my MH. I would like to use it to charge my chassis batteries while plugged in to shore power. Is this the way to go or is there a better device.

Thanks

[Dave78Chief]

That device is intended to recharge a multiple battery setup on a boat.

First question you have to ask yourself is:
Assuming you are always connected to shore power, do I need to recharge or just maintain the chassis battery?

If you are good about shutting down your rig so that only a small maintenance charge is needed, then a Trick-L-Start is all you need (only provides a max 5 amps.

If you have a odd situation where you expect to need a heavy recharge often, then you have several options:
1) The Magnum you listed
2) Xantrex Echo-Charge XANTREX Combiner at West Marine
3) Blue Seas Combiner SI-Series Automatic Charging Relay*—*Blue Sea Systems (bi-directional)
4) Intellitec Bi Directional Isolator Relay Delay - Diesel (BIRD) Battery Products (controls isolation relay [aux start relay])

There others.

Dave

[sdennislee]

Dave, Thanks for the detailed response. Based on your response, specifically option 4) Intellitec BIRD. I went back out to the coach as I knew I had seen the BIRD with diesel relay.

After reading that the BIRD I have 77-90006-120 is not continuous duty, thus the need for the diesel relay, it has me thinking that since the chassis batteries showed a charge of 12.77 V when I checked them, the BIRD saw no need to apply charging voltage to that set of batteries. I assume if the chassis batteries were to discharge to something less than 12 volts the BIRD and relay would kick in and charge the chassis batteries and I would see something on the order of 14.5 volts being applied.

I hope I am correct in this assumption.

[Dave78Chief]

This is the manual for your BIRD Controller (00-00839-100): http://intellitec.com/pdfs/BATTERY_web/5300839.100.pdf

It should energize the Big Boy relay (77-90006-120) if either side (Alternator or Inverter/Charger) voltage is => 13.1VDC except when using the generator.

So, as you discovered, you already have a battery combiner that will allow full high amperage charging capability of both batteries systems.

Dave

[sdennislee]

Thanks for the help. Noticed you have been answering a ton of electrical questions on the boards here lately. Nice to have a guy like you around that is willing to share and help out.

It would seem something is amiss with my charging system. The attachment you supplied states if either battery bank see voltage above 13.1 the control will close the isolator relay to parallel the 2 banks (chassis and house) and charges both. In my coach this true when the engine is running. However when connected to shore power and the charger is switched on as indicated by the Magnum ME-RC Remote the chassis batteries measure 12.77 and the house batteries measure 14.4. SInce the house batteries are over 13.1 the relay should close and charge both which should be indicated by a measurement of 14.4 on the chassis as well.

Looks like I'll be spending tomorrow chasing this down.

Thanks for your help.

[Diplomat Don]

sdennislee.......Here is what I've found.......My coach (same manufacturer as yours) had the same issue. I initially installed a Trick-L-Start unit which is the cheapest of the products and the cheapest made unit. It worked well for a few years, but the indicator lights started malfunctiuoning, even though the unit still worked. The phenolic back of the unit swelled, so I replaced it.

I bought the BIRD circuit board for my coach which just plugs into the front run bay. It worked, but several people were having issues with it eating up the Big Boy solenoids and charging at times you didn't necessarilly want it to charge. Fearful of issues I removed it.

I finally setteled on the Xantrex Echo charger, which is a good quality unit. Magnum's unit does the same thing, but I believe this is the most expensive unit of the three.

I would recommend the Xantrex unit and shop several websites. There was at least a $30.00 difference between sites.

Some will post that they just run a jumper wire or plug in a Battery Minder. This will work, but I wanted something permanent that works behind the scenes with no fuss.

[sdennislee]

Don,

THanks for the advice. Behind the scenes with no fuss is my goal as well. Still running down the issues trying to understand exactly what is and isn't working with the charging system as a whole.

I pulled the shore power an hour or so ago, turned on the head lights to force the chassis batteries to drain. Going to run them down to 12 volts then connect the shore power to see if they charge. I plan on repeating this process a couple time to verify it works each time. If they charge I will leave things as they are if not, I will follow your suggestion.

[Dave78Chief]

sdennislee,
I understand your concern about it not appearing to kick in from the Coach side charge. You might try calling Intellitec and ask them the question. If you do, make sure you tell them you have the 00-00839-000 version. It appears the 00-00839-100 version (manual link above) replaces the 00-00839-000 version you have (http://intellitec.com/PDF/5300839.000.pdf). It may be that the -100 version fixed the solinoid issue Don mentioned but I do not know. The Diesel-2 model is supposed to be for the larger solinoids like you have. The -000 model manual says trigger point is 13.3 vs 13.1 volts but still thats below the 14.4 volts you said you have. Use your voltmeter to check the actual voltage at the Coach Battery pin at the BIRD controller to ensure it sees the 14.4 value there in order to ensure you do not have a bad wiring connection.

Like the Trick-L-Start, the Xantrex Echo charger is a one-way vs Bi-directional device (BIRD is Bi-directional). Does not control the solinoid.

The Magnum is bi-directional and can be connected either with or without a solinoid http://www.magnumenergy.com/Literatu...20Rev%20A).pdf. I do not know if it can drive the big boy solinoid you have.

Dave

[sdennislee]

Dave/DOn,

Thanks for all the help.

I think everything is working as it should.

As I said I discharged the coach batteries to 12 volts, then plugged into shore power. I repeated this 3 times. Each time the coach batteries where charged back up. Currently setting 13.95.

I think my concern/confusion came from expecting to see 14.4 volts during charge cycle form the charger as I do when the alternator is the charging source.

Seems to be all is well.

Thanks again for all your time in replying to my questions. Very helpful in sorting this out.

Merry Christmas