Jumper wire from house to chassis batteries

[crah]

What are the draw backs from jumping a cable from the positive house batt to the positive of the chassis batt? I haven't bought any type of echo charger or equivalent yet. Obviously if you run down your batteries you won't be able to start the engine. Only other thing I can think of is mixing different battery bank types. Not sure what kind of problems this may create.

["007"]

If your tring to keep chassis batteries charged you could try using a Trik-L-Start that would feed off the house batteries.
You may also have a battery boost button on dash that would connect the house batteries across through a relay to your chassis batteries if they, chassis, have a weak charge.

[GaryR.]

Crah, I have a Riata 37' 300 CAT and I did that and it worked excellant for 9 years! I had one of those large battery shut off keys from Harbor Freight in that line that I would shut off when leaving the campground and before starting the motor home. I had 2 12 volt batteries for the chassis and two 6 volt ones for the house. It worked beautifully UNTIL I took all the batteries out and cleaned the cables and terminals. Then when I put them all back in I made a HUGE mistake and hooked the wire to the + terminal on the 6 volt battery that also had the cable running to the - terminal on the other 6 volt battery instead of putting it back on the + main terminal on the 6 volt. When I turned the harbor freight key on that wire became extremely hot, melting the outside insulation on it and melting part of a 105amp circuit breaker. Then the inverter started acting up. I unplugged everything and ordered a new circuit breaker. When I put it back together again after a couple of days everything seems to work as it should. I put in 2 12 volt batteries on the house side and as everything seems to have returned to normal I AM DOING IT AGAIN. I didn't learn from my first mistake! Good Luck Gary

[Missouri Mik]

Crah,

On my former SOB I used a 1 ohm, 10 watt resistor, 2 battery clips and short piece of wire from an old battery charger, to connect the positive terminal of the house battery to the positive terminal of the chassis battery through the resistor. Just connected it when I was connected to shore power and in one place for and extended time, mostly when it was in my driveway. Always disconnected it before I started engine. I have been using it for 5 or 6 years with no apparent ill effects. I recently started using it on my recently purchased 01 Diplomat. I put a clothespin reminder on my ignition key to remind me to disconnect before I start engine.

I am new on the forum and this is my first post.

Mike
01 diplomat, 350 ISC
01 Chevy Malibu toad

[mfire1339]

Crah,

I believe your Scepter has a bird system to keep all batts. up. Give Monaco a call.





Mike

[Coached]

I think you want to keep your chassis and house batteries separate under all circumstances? Most coaches have a "one time" switch that will "connect" the two banks for emergency or hard starting? If your chassis batteries are dead you can use your house batteries to start your generator to charge the chassis batteries - if the house batteries are dead you can start the engine and let the alternator charge the house batteries? If you connect all of them and they all die ................?

[Qwert66]

The more batteries tied together to a single charger = less battery life to some as some cells/batteries will get more charge that the others due to their differences in internal resistance. Add that on top of serial and/or parallel hookups and it doesn't get better only worse. It's not practical to independently charge each cell (best way) so we comprimise at the expense of battery life.

Chassis batteries are designed for short high burst outputs using only the top part of the capacity.

Coach batteries are designed for longer duration mild outputs to use appx. 80% of their capacity.

Hard tieing them together is only recommended to get out of an emergency situation and should not be considered for plan A.

That is why they have isolator systems (B.I.R.D.'s) that do a good job of managing for the emergency situation while offering a "charge both" option from either the converter OR the engines alternator only once the priority set is close to fully charged.

The drawbacks are - many sparks and heat build up in the jumper during connection.
Masking the condition of the individual batteries. Ending up stranded with no alternate battery source for starting the engine and/or genny. Poor life when tieing 2 different battery compositions together. Higher long term cost.

Keep em wet.

[ImagineIF]

If you don't have a combiner today, here's the most effective solution and easiest to install. Maybe some day the RV industry will look to the marine industry for what they've done. This might be a couple dollars more than piecemealing a high current solenoid and BIRD controller. The installation ease and better specs make it well worth the couple extra dollars.

ML-Series Automatic Charging Relays (Magnetic Latch) - PN - Blue Sea Systems

Gil
08 Contessa 42

[crah]

Thanks everyone. I guess I got the responses I expected either though I wanted to hear differently. Looks like its time to buy the echo charger. My coach doesn't seem to have the BIRD as I cannot locate it and if it is there it doesnt work.

[Dutch Star Don]

crah......The wire idea will work, but everytime you start the coach you'll need to remember to disconnect the wire. Your engine also charges your batteries and generally selects the group that is lowest. With them tied together (forget to undo wire) you may cause issues, like overtaxing your alternator.

It just isn't worth using a mickey mouse wire connection on an expensive coach and having to remeber to disconnect. Always try to make life simpler, not more complicated.

[Bobs911]

If I'm parked or stored for an extended time, I will jump the two banks together to keep the chassis batteries charged from my solar.

I always carry a short lawn tractor battery cable to jump the dual battery relay in event of alternator failure. Then I can run the genny to keep the chassis batteries up.

[garym114]

Originally Posted by Bobs911

If I'm parked or stored for an extended time, I will jump the two banks together to keep the chassis batteries charged from my solar.

I do the same. Works for me!

[crah]

Originally Posted by Diplomat Don

crah......The wire idea will work, but everytime you start the coach you'll need to remember to disconnect the wire. Your engine also charges your batteries and generally selects the group that is lowest. With them tied together (forget to undo wire) you may cause issues, like overtaxing your alternator.

It just isn't worth using a mickey mouse wire connection on an expensive coach and having to remeber to disconnect. Always try to make life simpler, not more complicated.

Thanks Don I should know better. You know the motto "keep asking until someone says yes". I had the mental notion to save a couple of bucks because I just gave source engineering the green light to fab my sway bars. I will need pointers on installing them. When I get them, I'll shoot you an email. I spent about 3 1/2 hours under the coach on Sunday removing the rear jacks to get the seals replaced. Boy am I paying the price on that today.

[Dutch Star Don]

The only tough part about the sway bars is drilling the holes in the frame. A sharp bit, good drill, goggles and a towel you can cover yourself with from the waist up. There are some serious metal shavings produced.