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Old 12-30-2018, 03:42 AM   #1
Junior Member
Brand: Thor Motor Coach
State: Alberta
Posts: 2
THOR #13068
Palazzo battery charging/solar questions

Hi all, big user of forums, low volume poster. A sincere thanks to all who provide info to this valuable resource.

I have a 2014 Palazzo 35.1 with 4x6volt house batts, and 2x12volt chassis batteries. I live in Canada and park the rig most of the winter. Because there are 6 batteries and they are not on a pullout tray, I don’t want to pull the batteries when parked for the winter, so I have been visiting the coach every second week to run the generator and charge them up. Couple questions...

1. The house batteries are new this year, 220 amp hours @ 6volts each (total 440 @ 12volts) and batts go down to 12.1v from 12.7 in two weeks... so about 50%. This is with USE switch and master power switch turned off. Is this normal? What would be drawing that much power? By my calcs, that is about 15 amp hours per day of loss. (Not counting loss on the chassis batts)

2. After I run the generator, the step works even with the switches off, but when I return to the coach 2 weeks later, it doesn’t come out until I either fire up the generator or hit the boost switch. Where does the step get power? (House or chassis)? Does this imply my chassis batts are dead after two weeks? The dealer was supposed to have tested them when I bought this summer, but may have only tested the house batts.

3. I have now (just yesterday) installed a 100 watt solar panel which gets some sun, but fairly low sun due to my location. In one day it charged the batts from 12.3 to 12.6 volts, so I know it works, but I am wondering what level of power (amps or volts) is needed to activate the bird (bidirectional relay) so the chassis batts get charged too. Anyone know?

Thanks in advance for any help!

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Old 12-30-2018, 06:55 PM   #2
Senior Member
Brand: Thor Motor Coach
Model: Palazzo 36.1
State: North Carolina
Posts: 320
THOR #13712
Hi Mangler, I have some of the same questions on my 2018 Palazzo 36.1. Solar charge switch does not show anything as far as current being generated even though it's in full sun yesterday and today. Hopefully a Forum member is Solar literate because I'm not!

Chuck and Mary Ann
FMCA, Good Sam Life Member and Thor MC member

Enjoy the journey, one day at a time!
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Old 12-31-2018, 12:55 AM   #3
Senior Member
Brand: Thor Motor Coach
Model: 2013 ACE 30.1
State: Alberta
Posts: 1,144
THOR #2631
G’day from the Great White North eh hoser.......OK so much for the Bob and Doug McKenzie impersonation fellow Albertan: Not familiar specifically with your coach but......

1. 12.1 volts is probably between 25% and 50% state of charge.....but if you assume 50% gone then the A/H draw is about 1/2amp or less per hour (assume load in use 24 hours/day for 14 days) unless I goofed somewhere on the bean counter. So how about any devices that are hard wired off batteries like your gas detector; radio memory off chassis batteries usually; hard wired inverter via fuse not passing through battery disconnect perhaps.....or I have heard of some radios bypassing disconnects.

2. Steps are usually powered from chassis battery. They may not be dead, but could be below some threshold the step controller requires to function properly.......measure your chassis battery voltages and check your step manufacturer’s info on minimum voltage/current requirement. Not sure if they spec that though. Load testing all batteries is the best bet but not easy when the weather is crappy.

3. Bird info says either battery string being charged at minimum 13.1 VDC for 2.5 minutes will connect the strings together.
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Old 12-31-2018, 02:19 AM   #4
Thor Palazzo 33.3 diesel
TurnerFam's Avatar
Brand: Thor Motor Coach
Model: Palazzo 33.3 34'bunkhouse
State: Georgia
Posts: 2,421
THOR #4735
1. it actually sounds like your House batteries are holding up very well over several weeks... there will also be draws on the batteries unless you PHYSICALLY disconnect them...you don't have the REMOVE them, just install a disconnect, found at any auto parts store, on either the positive or negative terminal of the battery 'bank'.
For the Chassis batteries, there should really be nothing to cause them to lose any charge if you are using the rotary 'main' disconnect... I've never had ANY issue with my steps or starting the coach, even after months of non use, and I don't even turn the rotary disconnect to the chassis batteries... 2) but, yes, the steps draw power from the Chassis battery bank, and are tied into your ignition.

3. I have 2 100w solar panels, and they seem to take very good care of the House batteries, on good sun days, when in storage, but I've never expected them to have anything to do with also charging the Chassis battery bank. The output of solar is probably not going to ever be enough to trigger the BIRD, if able, to output also to the Chassis batteries. I'm not even sure it would, in any case, since your Solar is simply going directly to the House batteries, NOT thru the BIRD.

enjoy... : )
the Turners
'14 Palazzo 33.3 bunkhouse 34' diesel
KingTailgater2 Dish HD, 100w/5a SOLAR, BlueOx
100,000+mi since '14 - US, Alaska, Canada - Northwest, GA! (also, '14 Gulfstream Amerilite and '07 ForestRiver Rockwood) : )
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Old 12-31-2018, 09:05 AM   #5
Junior Member
Brand: Thor Motor Coach
State: Alberta
Posts: 2
THOR #13068
Thank you all! I will be visiting the coach later today (15 min drive), and I will ne checking the chassis batts more thoroughly. We will see how it goes. I will report back.
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batteries, bird, charging, solar, step

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