What Charges the House & Chassis Batteries When

[10scDust]

Thanks for that clip Bob, it brings back wonderful memories of my youth, watching the B horror movies host, late night Fridays, on Cleveland, Ohio tv, Ghoulardi, later the Ghoul.
Played this weekly, lol, usually with a clip of a toothless old man flapping his chops!
Never saw this version.

[10scDust]

Thanks for a tip somewhere, found our battery isolator under the hood, hidden by the radiator's reserve reservoir.
Intellitec Isolation Relay Delay, with a trombetta solenoid, is what is installed there.
Our Trombetta has failed and we are upgrading to a Precision Electronics BIM 225 and eliminating the Intellitec/Trombetta set up.
Great forum folks! Thanks again!

[GCVolkman]

Originally Posted by bevedfelker

There have been a lot of responses on various threads of this forum about what (generator, shore power, and engine alternator) charges what battery (chassis, house) when. In researching technical topics for the Axis/Vegas Owners' Manual I compiled I found information about the Bi-directional Isolator Relay Delay (BIRD). Reading about the BIRD I had the impression that it sensed voltage from the alternator, generator, or shore power and automatically switched charging current to both the chassis battery and house batteries. This left me confused when so many answers to questions on this forum implied that the chassis battery was not charged when running the generator or on shore power.

To try to get a good answer, I sent the following email to Thor Customer Service: "I have a question regarding battery charging -- both chassis and house batteries. I know the chassis battery is charged by the engine alternator. I also know the converter charging circuit charges the house batteries when on shore power or the generator is running. Here are my questions. I have asked several owners and I've gotten more and different answers than I've had questions: 1. Does the alternator provide power to charge the house batteries when driving down the road? 2. If so, dose the USE/STORE switch have to be in USE? 3. Does the converter provide power to charge the chassis battery as well when on shore or generator power? 4. Does my 2015 Vegas 24.1 have a Bi-directional Isolator Relay Delay (BIRD) or is there a BIRD-like circuit in the Battery Control Center (BCC)? 5. Does the BIRD function in both directions; that is, alternator power going to both chassis and house batteries as well as shore/generator power going to both house and chassis batteries? 6. Can I gat a Production drawing of the BCC and also the BIRD (if there is one). Sorry for the myriad questions but how the batteries charge and from where they get their charging power is driving me crazy."

Today I received the following answer from Thor: "Hi Ed, Thank you for contacting Thor Motor Coach. When your coach is going down the road with motor running, it is charging all the batteries – chassis and house. When the coach is sitting plugged into shore power or generator running it is also charging both – chassis and house batteries. For this to happen, motor running or plugged in the USE / STORE switch needs to be in the USE position. I believe the Bird or Bi-directional relay for your coach is under the hood on the driver’s side. But the main part is that yes the system should charge all batteries going both ways. Hope this helps."

When the BIRD senses 13.1 volts for 2.5 minutes on the chassis battery the relay isolator will close sending charging current to the house batteries (alternator providing charge to house batteries. Going the other way when on shore power or running the generator when the BIRD senses 13.1 volts for 2.5 minutes on the house batteries the relay isolator will close sending charging current to the chassis battery (generator or shore power charging the chassis battery).

Given this, the BIRD should keep all batteries charged when the engine is running, when you are running the generator, or when you are on shore power. For this to work for the house batteries, the USE/STORE switch must be in USE. Atch from Intellitec explains BIRD operation.

Sorry for the long explanation, but from the myriad questions regarding battery charging on the forum I thought this would be helpful.

Thanks. Does this apply to a 2016 Axis 24.1 as well?

[Oneilkeys]

Yes. It applies to the 2016 Axis 24.1. I have one too.

[cil1dcm]

I just bought a used 2016 ACE 30.1 and voltmeter readings look funky. Using your information to check stuff, but was there a mention of some kind of manual that might tell me where and how to find the bird and the other parts tied in to this motorhome ?

[Beau388]

Originally Posted by cil1dcm

I just bought a used 2016 ACE 30.1 and voltmeter readings look funky. Using your information to check stuff, but was there a mention of some kind of manual that might tell me where and how to find the bird and the other parts tied in to this motorhome ?

The BIRD and its controller (Trombetta) located at the very rear of the house battery compartment high on the front (of the coach) wall. Thor MC battery cables are 4 ga or 2 ga where as the cables to and from the BIRD is 8 ga like the cable between the coach batteries and the power center. Later coaches use a BIM which is solid state and up near the chassis battery

[arborlakes4us]

does this also refer to a 2016 thor windsport.that coach batteries are charged with the engine while traveling ?

[Rich1339]

I have a solar battery maintainer, trickle charger. I plugged it to the cigarette lighter adapter ( dating myself) and placed the solar on the dash to collect the free sun rays.

anyone have a thought on weather the User switch needs to be on???

[Beau388]

Originally Posted by arborlakes4us

does this also refer to a 2016 thor windsport.that coach batteries are charged with the engine while traveling ?

Yes, provided the store/use switch is in the USE position and the BIRD is working as installed. The reverse is also true - when plugged-in to shore power or the generator is running the coach's charger should keep the chassis battery charged. That's why the relay in BIRD is called "bi-directional".

[petefoss]

Originally Posted by Rich1339

I have a solar battery maintainer, trickle charger. I plugged it to the cigarette lighter adapter ( dating myself) and placed the solar on the dash to collect the free sun rays.

anyone have a thought on weather the User switch needs to be on???

On my 31W the dash 12V socket is connected to the chassis battery and on all the time. So the use/store switch is irrelevant as far as the chassis battery is concerned

[petefoss]

I thought about one of them but at least the cheap ones never shut off so they could over charge the battery.

[frschof]

What type of solar unit did you buy to maintain your House battery. THe one I have dosnt seem to be do the trick. I have the solar unit on the roof. https://www.amazon.com/SUNER-POWER-B...=thedrive09-20

[petefoss]

Originally Posted by frschof

What type of solar unit did you buy to maintain your House battery. THe one I have dosnt seem to be do the trick. I have the solar unit on the roof. https://www.amazon.com/SUNER-POWER-B...=thedrive09-20

I use a minder plugged in inside the coach to maintain the chassis battery while plugged in to maintain the coach with the regular converter/charger.

With my old inverter my coach draws about 1 kwhr per day with nothing except parasitic loads. So a 100 watt panel would be about right to maintain long term. Although since I changed the inverter I should run the test again.

[frschof]

Well I quess this 6watt solar panel is not going to maintain my battery. That was a waste of money. the 100watt is what I need. Tks for the info.

[bry899]

Originally Posted by frschof

What type of solar unit did you buy to maintain your House battery. THe one I have dosnt seem to be do the trick. I have the solar unit on the roof. https://www.amazon.com/SUNER-POWER-B...=thedrive09-20

Most Class C Motorhomes don't charge the Chassis battery, only when the engine is running, I added the Trik L Start:
https://www.lslproducts.net/TLSPage.html

It Charges the chassis batteries anytime there is shore, Generator or Solar power.
I have a 100 watt solar panel and it maintains all three batteries. Now I don't plug my Class C in to shore power when in storage (Outside).
I also don't worry about the Use/Store switch as the solar is wired directly to the batteries.

[AAL787]

Originally Posted by bevedfelker

There have been a lot of responses on various threads of this forum about what (generator, shore power, and engine alternator) charges what battery (chassis, house) when. In researching technical topics for the Axis/Vegas Owners' Manual I compiled I found information about the Bi-directional Isolator Relay Delay (BIRD). Reading about the BIRD I had the impression that it sensed voltage from the alternator, generator, or shore power and automatically switched charging current to both the chassis battery and house batteries. This left me confused when so many answers to questions on this forum implied that the chassis battery was not charged when running the generator or on shore power.

To try to get a good answer, I sent the following email to Thor Customer Service: "I have a question regarding battery charging -- both chassis and house batteries. I know the chassis battery is charged by the engine alternator. I also know the converter charging circuit charges the house batteries when on shore power or the generator is running. Here are my questions. I have asked several owners and I've gotten more and different answers than I've had questions: 1. Does the alternator provide power to charge the house batteries when driving down the road? 2. If so, dose the USE/STORE switch have to be in USE? 3. Does the converter provide power to charge the chassis battery as well when on shore or generator power? 4. Does my 2015 Vegas 24.1 have a Bi-directional Isolator Relay Delay (BIRD) or is there a BIRD-like circuit in the Battery Control Center (BCC)? 5. Does the BIRD function in both directions; that is, alternator power going to both chassis and house batteries as well as shore/generator power going to both house and chassis batteries? 6. Can I gat a Production drawing of the BCC and also the BIRD (if there is one). Sorry for the myriad questions but how the batteries charge and from where they get their charging power is driving me crazy."

Today I received the following answer from Thor: "Hi Ed, Thank you for contacting Thor Motor Coach. When your coach is going down the road with motor running, it is charging all the batteries – chassis and house. When the coach is sitting plugged into shore power or generator running it is also charging both – chassis and house batteries. For this to happen, motor running or plugged in the USE / STORE switch needs to be in the USE position. I believe the Bird or Bi-directional relay for your coach is under the hood on the driver’s side. But the main part is that yes the system should charge all batteries going both ways. Hope this helps."

When the BIRD senses 13.1 volts for 2.5 minutes on the chassis battery the relay isolator will close sending charging current to the house batteries (alternator providing charge to house batteries. Going the other way when on shore power or running the generator when the BIRD senses 13.1 volts for 2.5 minutes on the house batteries the relay isolator will close sending charging current to the chassis battery (generator or shore power charging the chassis battery).

Given this, the BIRD should keep all batteries charged when the engine is running, when you are running the generator, or when you are on shore power. For this to work for the house batteries, the USE/STORE switch must be in USE. Atch from Intellitec explains BIRD operation.

Sorry for the long explanation, but from the myriad questions regarding battery charging on the forum I thought this would be helpful.

BIRD is the word!

[Jdb]

Thor has been using the BIM 160 since at least 2018 - likely back to 2017. I confirmed this by getting the electrical schematic TEE2937-00, which clearly shows the BIM 160. Previously they used the BIRD, and the tech rep I spoke with told me that my unit had a BIRD from the factory; however the schematic they sent me shows the BIM 160 installed by Thor.

The BIM 160 adds a connection for battery cables from both Chassis and Coach battery banks. The BIM 10 manufacturer confirmed that This enables charging of the coach battery while the engine is running, even if the On/Store switch is "off".

Dave

[Oneilkeys]

In the BIRD/Trombetta setup, the Trombetta provides the two connections to both battery banks and the BIRD just provides the means to open or close those connections. In my 2014 Vegas and 2016 Axis, it was the way Thor hooked them up. For some reason, the house battery banks were wired to the on/off switch and not directly to the house batteries. Thor may have wired the BIM equipped Axis/Vegas differently. But it is easy to check. Just see if you are getting 13.5+v at the house batteries on both shore power and engine alternator.

[GordSanClemente]

Sorry for going to an old thread.
I have a 2019 ACE 30.3.
I switched to lithium house batteries.
I assume that the original setup will jump to a float charge and not fully charge my lithium battery. Thoughts?
Should I be upgrading one or all of these components (not sure which I have) ?
Thanks,
gordon

[Oneilkeys]

I don’t know what lithium batteries you have, but many have built in protection systems that allow the use of a standard charger. You should check with your manufacturer to make sure. However, a standard charger will not charge the lithium batteries at the full 14.6v so it will not fully charge the lithium batteries. In addition, a lithium charger supposedly charges lithium batteries 5X faster than acid batteries can be charged. I do not believe that will happen with a standard charger. The BIRD/Trombetta or BIM does not charge the batteries. All it does is to open/close the solenoid (Trombetta) to charge both battery banks at the same time.