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Batteries

Problem: 2000 U320 / Shore power plugged into a 110V AC outlet. Inverter, boost and main battery disconnect switch (by front door) were in the on position for long term storage.  The main breaker in the storage lot flipped to the off position for several days and my batteries were drained. Several other RV's were also plugged into the same circuit. With the power at the main pole off is it possible that the other coaches were drawing down my batteries?
Was I correct in leaving the inverter, boost and battery disconnect in the on position during storage?
Patrick & Delois
2000 U320 40'

Re: Batteries

Reply #1 –
I believe if you have boost on and power goes off you will flatten both sets of batteries. I would leave boost off and put on a trickle (or other kind) of charger on Isolator so that keeps your engine battery up and if power goes out for a while only the coach is affected. This way at least you can run the engine. I would consider (others may correct me) if it was me leaving it for a long time to take off the nuetral lead on all batteries esp' the engine one
John
Coachless, now use aircraft. 2003 Ford Travelair TC280 class C. Super shape. Just for 1 yr .
1994 Ford E350 ClassC,total renovation inside and out. Now sold.
2000 U295  36' Cummins 350 c/w Banks Stinger, Resonator upgrade,Solar, LED lites.Residential fridge with slide out pantry. Build 5674. Sold
ex 92 GV 022C ored Cummins. Sold
ex 95 GV240 cat 3116. Sold
2017 Mini cooper s & 2016 land Rover LR2 HSE  LUX.
jhaygarth@aol.com    SKP #130098
treat everyone as you would like to be.

Re: Batteries

Reply #2 –
Was I correct in leaving the inverter, boost and battery disconnect in the on position during storage?

I would say no.

Leaving the inverter on and the battery diisconnect on guarantees dead house batteries if you lose shore power.

Leaving the boost switch on guareantes dead chassis batteries also.

You want to leave the charger on and the battery disconnect in the on (not disconnected) position so shore power will keep the house batteries charged, but the boost switch off so an unexpected loss of shore power won't take down the chassis batteries.  Or you can disconnect all the batteries and use an external shore-powered charger/maintainer.

Use some type of battery maintainer to keep the chassis batteries charged.

If you lose shore power for a week or two, you will probably have dead house batteries, but still have enough juice in the chassis batteries to get the engine started, and then start the generator if necessary.

Long term storage without shore power or solar requires physically removing the negative leads from both sets of batteries to prevent discharge.
Tom Lang K6PG (originally  KC6UEC)
and Diane Lang
2003 38 U295 build 6209
2016 Jeep Grand Cherokee Summit Ecodiesel
still have tow-ready 2006 Acura MDX 
Temple City, California
Motorcade 16681 California Chapter President
SKP 16663 member of SKP Park of the Sierra, Coarsegold California
FMCA F071251
Retired electrical and electronic engineer

Re: Batteries

Reply #3 –
Quote from: John Haygarth –
I believe if you have boost on and power goes off you will flatten both sets of batteries. I would leave boost off and put on a trickle (or other kind) of charger on Isolator so that keeps your engine battery up and if power goes out for a while only the coach is affected. This way at least you can run the engine. I would consider (others may correct me) if it was me leaving it for a long time to take off the nuetral lead on all batteries esp' the engine one
John

John,

Yes, right on all counts. The boost solenoid starts using juice (to maintain closed contacts) when the dash switch is turned on and will run the batteries flat in no time without shore/solar power. Even with the main battery disconnect switch in the off position, the CO monitor is still powered along with the 12V power to the fridge processor board, maybe some other small draw also. Winter storage needs battery cables disconnected. Summer storage needs some kind of power if left any length of time. Trickle charger excellent if 120V available. Newer trickle charges should not charge engine batteries with more than about 13.1V. Check with digital meter at battery.

Inverter will exhaust batteries in hours if power goes off. Plus, the fire danger with it turned on.

Cheap 45 watt panel on the roof will keep both batteries up without being plugged in to shore power while in outside storage.

Pierce
Pierce and Gaylie Stewart
'93 U300/36 WTBI
Detroit 6V-92TA Jake
1140 watts on the roof
SBFD (ret)

Re: Batteries

Reply #4 –
Thanks for the information. Just to clarify: I now have reliable shore power. The boost switch is in the off position and the positive lead has been disconnected on the cranking batteries. The inverter and the battery disconnect switch ( by the inside front steps) are both on. This was done to charge the coach batteries. Pierce, you mentioned the possibility of a fire. Is this rare  or should I not use the inverter to charge the coach batteries? Also, is it necessary to leave the battery disconnect in the on position when charging?
Patrick & Delois
2000 U320 40'

Re: Batteries

Reply #5 –
Quote from: Griff –
With the power at the main pole off is it possible that the other coaches were drawing down my batteries?

No... the AC circuits of other coaches plugged into the same pedestal as yours is cannot drain your batteries. They are two isolated circuits.

Quote
Was I correct in leaving the inverter, boost and battery disconnect in the on position during storage?

That depends on whether your inverter is also a battery charger. If you have a separate converter/charger then you do NOT want your inverter to be left on. Inverters all have an idle current which is usually somewhere under 0.5 amps; plenty of current to drain you battery bank in a day or two. If you have an inverter that also operates as a charger then the charger must be left on but the inverter side should be turned OFF.

The boost problem has been covered by others... but I'll repeat. The dash switch just controls a solenoid which draws current from the batteries to stay in the position. This current will drain you batteries if there is no outside source of power.

Best bet is to install a solar panel on the room and a charge controller. A few hundred bucks and you no longer have to pay for - or worry about - power from the storage pedestal again.

Leaving the battery disconnect switch ON will enable all the transient devices (dash clocks, memory for am/fm radios, etc.) to continue to operate. If (when!) the shore power goes out all of these will begin to drain your batteries.

The solar panel upgrade fixes this, too.

Craig
1993 U225 36' Unihome GV with PACBRAKE exhaust retarder, Banks Stinger and Solar Panels.
Toad: 1999 Jeep Wrangler 2-door soft-top.

"No one has ever had to evacuate a city because the solar panels broke."

Re: Batteries

Reply #6 –
Leave the inverter off. The charger side of an inverter is automatic. The invert side runs all 120 v plus a draw on the batteries to run the inverter itself when the power goes out.
1994 U280, Build 4490
Deming, NM.

Re: Batteries

Reply #7 –
For clarity, the main battery disconnect by the front door will not affect the charging of the batteries when plugged to shore power.  I personally disconnect the negative terminals on all batteries (Cole Hersee disconnects, I do not have poert at the coach storage location.  See my pictures in Photos/Files).
Peter & Beth Martin
No Forrest? What have you done?
MC# 15890 until Dec 2016; FMCA #F329677
Cincinnati, OH

Re: Batteries

Reply #8 –
Quote from: Griff –
Thanks for the information. Just to clarify: I now have reliable shore power. The boost switch is in the off position and the positive lead has been disconnected on the cranking batteries. The inverter and the battery disconnect switch ( by the inside front steps) are both on. This was done to charge the coach batteries. Pierce, you mentioned the possibility of a fire. Is this rare  or should I not use the inverter to charge the coach batteries? Also, is it necessary to leave the battery disconnect in the on position when charging?
Griff, if you are going to take the cables off of the batteries, the ground should be the first and last cable you connect.  By doing it that way it helps prevent voltage spikes that engine computers don't like. Also if your coach has a link 2000 control panel you can leave the charger on, and the inverter off when you store the coach. You have an inverter/charger 2 functions in one, that can be controlled separately no need for the inverter function when the coach is stored or hooked to shore power. The "inverter" function if turned on draws current weather you have anything plugged into it or not.
Bruce, Linda, and Macy
Zoey RIP 1/20/19
1999 U295 40' build #5400
2017 silver Jeep Wrangler, 1260 watts of solar on top
Moving around the country
 

Re: Batteries

Reply #9 –
Griff,
To HELP with any confusion,
WHY DISCONNECT THE NEGATIVE BATTERY LEAD FIRST AND REPLACE IT LAST?
1.      Automotive and industry battery standards call for NEGATIVE ground systems.  Many years ago, some (mostly European) car manufacturers didn't get that memo, but they are on board now.
2.      So we have negative ground systems in our cars and coaches (the vehicle frame becomes "ground" and only positive wires have to be run to devices in order to power them - cuts the number of wires in half!).  The device, in turn, is either mounted (physically grounded) to the frame or has a ground wire attached to the frame in order to complete the current flow;  i.e. - from the positive terminal of the battery, through the single power wire, through the device, through the frame and back to the battery negative terminal through its ground cable.
3.      Circuits/powered components (with rare exceptions) are oblivious as to where (+) supply or (-) ground their power is "cleanly" interrupted.  They just stop functioning because their circuit flow continuity has been interrupted.  Computers and intrusion alarm systems, etc. can be inadvertently triggered and/or damaged by "less-than-clean" power removal (by rapidly spiking the component ON and OFF multiple times as a (+) or (-) lead is lifted from the battery terminal.
4.      BUT from a PERSONAL SAFETY standpoint, if your wrench should slip or inadvertently touch something else as you are removing a cable from your battery, what would the consequences be?
    • If your battery ground cable is in good condition (working properly) and one end of your wrench is on the negative battery terminal when the wrench slips, what happens?  If the other end of the wrench contacts any of the surrounding components/framework (save the positive battery terminal), your wrench has just become another ground path to the frame, in parallel with the already existing negative ground cable, and nothing bad happens.
       
    • BUT, if one end of the wrench is on the positive battery terminal and the other end of the wrench contacts any of the surrounding components/framework, including the negative battery terminal, something bad does happen.  You have essentially placed a conductor (the wrench) from positive to negative, across the battery terminals.  Because even small batteries have lots of stored potential energy, when they are short circuited, they release that energy with great GUSTO, welding wrenches to bulkheads, burning holes in sheet metal, spewing weld splatter, turning wrenches into red hot pokers, flash burning eyes and soiling perfectly good underwear.
SO,
DISCONNECT NEGATIVE FIRST
CONNECT NEGATIVE LAST
The same logic works for all negative ground battery systems, regardless of application or use (automotive, truck, home yard equipment, battery chargers, jumper cables, etc.).
FWIW,
Neal
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Neal (& Brenda) Pillsbury
'02 U320 SPEC, 4200, DGFE, Build #5984
'04 Gold Wing
'07 Featherlite 24'
'14 Jeep Grand Cherokee Summit
MC #14494
Exeter, NH & LaBelle FL
Quality makes the Heart Soar long after Price is Forgotten