Isata 3 - Batttery 101

milkman55 · 05-21-2017, 05:05 PM

I just got my Isata 3 last month and already dealing with battery issues. I would assume there are many new owners that have some of the same basic questions about the chassis and house batteries. I thought starting a thread just on batteries might be useful. There is a similar thread for the REV with lots of good info, but not specific to the Isata 3.

The first week my Isata was parked outside and the solar panels kept everything charged even though I was not plugged into power. I wasn't really running anything and had the coach disconnect set whenever I was not in the coach working.

After the first week, I moved it into my enclosed storage unit, but did not plug into shore power (15 amp). I had the disconnect set and thought it would last the week I planned to be out of town.

When I got back the chassis battery was completely dead and the house battteries where at 8.4v. I plugged into the 15 amp shore power and the chassis batteries came back to 13.6v pretty quick. I used the emergency start and was able to get the engine started but it ran just a few seconds and died. It seemed to me the chassis battery was charging from the shore power even though I understand they are supposed to be isolated systems? I later hooked up a Battery Tender Plus to the chassis battery via the charge connections under the hood and left it to fully charge the chassis battery.

I am still trying to figure out the drain on the batteries over a one week period when everything was in disconnect mode. Any thoughts on parasitic drains would be helpful. I know my rear view camera is a likely culprit because I believe it is wired to the wrong terminal (always on, not ignition) under the drivers seat. Also my Jensen TV power light stay lit even when the battery disconnect is enabled.

A couple of basic questions -

With enclosed storage the RV solar is obviously not going to help. Is it OK to leave the shore power plugged in whenever in storage and if so, should the battery disconnect be off or left on for the charging to be optimal? Any danger of damaging the AGM batteries if left plugged in for weeks at a time?

I ordered a cigarette lighter adapter for the Battery Tender and plan to use that in the lower aux power port which I understand is always live. Just plug the Battery Tender into the RV wall outlet and it should keep the chassis battery in good shape while in storage.

Thanks for any guidance.

**bclemens** · 05-22-2017, 07:46 AM

The house and chassis charge off of the converter and the alternator. Those systems are protected, but not completely isolated. The only thing we wire to the chassis battery is the step I think...and the emergency start line. There is a Bi-Directional Relay that controls that...maybe its not unlatching the two systems which lets them both draw down.

Parasitic draws would be the slide brains, but those are supposed to be minimal. Solar controller maybe??? if its not getting sun.

The Jensen may be on an inverted circuit? The inverter could be connected directly to the batt's for cabling, so I would turn the inverter off.

milkman55 · 05-22-2017, 08:20 AM

All good info, thanks.

I do know the rear view camera is tied into the chassis battery under the drivers seat. Because it was not connected when I picked up the RV, the techs connected it to what they thought was there correct terminal of the three options. Since the camera will power on even when the engine is turned off, so I think it's on the wrong post. Planning to check that soon, but need to get some Torx sockets to remove the seat.

I didn't power down the inverter when I flipped the chassis disconnect, so that will definitely be added to my shutdown checklist and may be the culprit. I do think that is why the TV power lights stayed on, so that should remedy any drain.

I will check the solar controller and see if it has a power off since the RV is stored indoors. Texas heat just too much to leave a new RV sitting outside.

The "accessories" sheet that gives all the model and serial numbers does not show a solar controller. Does anyone know the brand and model number for the solar controller that I can lookup a manual?

**bclemens** · 05-22-2017, 09:52 AM

It was a Zamp ZS-30A. I think Go Power just puts their name on that now.

VeniVidi · 05-22-2017, 10:25 AM

We have a 2017 Isata3 manufactured in October 2016. It has a Go Power solar controller located near other system controls at the top of the stairwell. Have attached an image. Model isn't listed on the equipment sheet we got.

If I remember an earlier thread correctly, there was a time interval when solar panels were installed by mistake on a number of Isata units. No controller though. Several forum members were trying to find controllers to install themselves.

milkman55 · 05-22-2017, 10:37 AM

Thanks, mine has the solar option installed and I have the controller. Just need to find out if it's drawing power when the unit is indoors and no sun. So many things to figure out.

Nobody has commented if they leave their Isata plugged into shore power when stored. Seems the Progressive converter model is pretty sofisticated with three charging levels to prevent overcharging. Also based on bclemens reply, I don't need a separate Battery Tender for the chassis battery since it's being charged by the Progressive converter when plugged in.

VeniVidi · 05-22-2017, 11:11 AM

There IS a lot to figure out. Forums have been helpful particularly for motor home newbies like my husband and me.

He's a mechanical engineer with many years of experience. Designed HVAC systems. Loves to tinker with vehicles.

And we're STILL having issues with some of the systems such as the Big Foot levelers not performing in a logical way and the Atwood AC fan not kicking off when it meets the cooling setpoint.

Dealership where we bought the Isata has been an exemplar of unresponsive and uninformed customer "service" so we bumble along hoping to fix or resolve on our own without causing further harm.

**bclemens** · 05-22-2017, 11:37 AM

99% of the bigfoot leveler issues are due to an improper null point. IE, it was never calibrated at a level point (or it has lost that point).

I can't remember if you guys got it figured out, but another user had the same issue on Atwood's and it was a bad sensor....but I thought theirs was the actual compressor. There is a known issue that the fan cannot just be "ON" it has to be set to "AUTO" to turn off when a set point is reached. If it is set to "Auto" then that sounds just like the other situation (or maybe it was your situation) that they said it was a frozen board.

camaraderie · 05-22-2017, 01:44 PM

The simplest way to avoid the dead battery issue is to insure that your battery is fully charged...then disconnect the negative wire...which will insure no drain and just normal self discharge which is 1% or less per month with an AGM. (Typically 10-15% in a wet cell so still ok for a couple of months minimum).
If you don't like physically disconnecting the neg wire. Put on a $7 switch from walmart like this:

milkman55 · 05-22-2017, 03:06 PM

Quote:

Originally Posted by bclemens

I can't remember if you guys got it figured out, but another user had the same issue on Atwood's and it was a bad sensor....but I thought theirs was the actual compressor. There is a known issue that the fan cannot just be "ON" it has to be set to "AUTO" to turn off when a set point is reached. If it is set to "Auto" then that sounds just like the other situation (or maybe it was your situation) that they said it was a frozen board.

I have a service appointment on May 30 with an Atwood service dealer to look at my AC fan issue. In "Auto", the fan never shuts off regardless of the set point, but the compressor is starting and stopping. Another owner on this forum mentioned their belief was the fan always runs regardless of the fan setting (even Auto) when the AC is active. My selling dealer diagnosed that the circuit board was "frozen" in the on position, but they didn't have a replacement circuit board and since they are 4 hours from my house, I decided to head home and go to a dealer near my house.

My fan on the heater cuts on and off based on the thermostat setting, just the AC seems to not be working as it should.

Frank tamez · 05-23-2017, 02:00 PM

Quote:

Originally Posted by milkman55

Nobody has commented if they leave their Isata plugged into shore power when stored. Seems the Progressive converter model is pretty sofisticated with three charging levels to prevent overcharging. Also based on bclemens reply, I don't need a separate Battery Tender for the chassis battery since it's being charged by the Progressive converter when plugged in.

Mine was plugged in 24/7 all winter in my climate controlled garage and everything was 100% come spring. Both house and chassis battery's were fully charged without the need for a trickle charger.

Frank

FFred · 05-24-2017, 06:23 AM

" Also based on bclemens reply, I don't need a separate Battery Tender for the chassis battery since it's being charged by the Progressive converter when plugged in."

Link to that reply?

milkman55 · 05-24-2017, 07:43 AM

Quote:

Originally Posted by bclemens

The house and chassis charge off of the converter and the alternator.

Let me know if you interpret this statement differently, but it appears to me the Progressive converter charges both the house and chassis. This is also what I believed I observed after plugging into shore power.

**bclemens** · 05-24-2017, 08:35 AM

Correct...there is logic built into the BCC (on the 3 series and 4 series) and the BIRD on the trucks that sense voltage and connect the batteries when appropriate.

FFred · 05-24-2017, 09:22 AM

That is great news! , I had the impression the unit only charged the house and not the chassis battery.

I wish the solar charge controller was set up the same way , charge both house and chassis , to make it easier when the unit is out of service , just parked in our yard.

**bclemens** · 05-24-2017, 09:32 AM

That requires a different controller. It can be done. Zamp makes a two battery bank controller...but that's asking those panels to do a lot.

ScottBrownstein · 05-24-2017, 09:42 AM

Quote:

Originally Posted by FFred

That is great news! , I had the impression the unit only charged the house and not the chassis battery.

I wish the solar charge controller was set up the same way , charge both house and chassis , to make it easier when the unit is out of service , just parked in our yard.

Frankly I don't see why it wouldn't already, provided that the charge converter can pump at least 13 volts into the house bank. The BCC doesn't know where the voltage comes from nor does it care. When it sees one bank over 13 (some as low as 12.7) and change, it parallels the other bank. Now, if you don't have enough current from your cells to power the isolation relay, it will just drop back down, but if you have 1 amp or more, you already should be charging the chassis from the house on solar. You don't need a 2 bank converter...you already have on in the BCC.

**bclemens** · 05-24-2017, 09:57 AM

The issue is that the BCC can be cut out with the disconnect. So we typically run the solar wires directly to the battery which is preferred.

ScottBrownstein · 05-24-2017, 09:59 AM

Quote:

Originally Posted by bclemens

The issue is that the BCC can be cut out with the disconnect. So we typically run the solar wires directly to the battery which is preferred.

Personally, I have always wondered why most FR products don't do that with the converter as well, but no matter. All he has to do is leave the disconnect turned on and the solar will get to both batteries through the BCC anyway.

**bclemens** · 05-24-2017, 10:04 AM

Then the solar is also trying to compensate for parasitic loads. We ran it that way at my last division and had issues, so we changed it direct to the battery. That way you can hit the disconnect to shut everything down, but the charge line from solar is still doing its thing.

People would hit the disconnect...because that's what they always do and would cut off their charging as well. We wired converter charge line that way as well so if you were plugged in it was sort of dummy proof. We rarely had issues with the chassis battery then.

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