What Charges the House & Chassis Batteries When

[Oneilkeys]

In this diagram, the Trombetta is the isolator relay. It is connected in this generic diagram thru the two disconnect switches for the house and chassis battery. But it does not have to be hooked up this way. You can also see the five wires coming off the bird. I believe mine only has four. One power, ground and one to each battery.

[Ag&Au]

Originally Posted by Oneilkeys

In this diagram, the Trombetta is the isolator relay. It is connected in this generic diagram thru the two disconnect switches for the house and chassis battery. But it does not have to be hooked up this way. You can also see the five wires coming off the bird. I believe mine only has four. One power, ground and one to each battery.

Thanks for the last two posts. I understand whats going on a lot better now.

Ken

[Chance]

Originally Posted by Oneilkeys

There is only one Trombetta in the Axis/Vegas. It is located on the right front when you open the hood. Here is a picture of the Trombetta with the BIRD next to it. One side if the Trombetta is connected to the house batteries and the other to the chassis battery. It us noting more than a relay that opens and closes to connect and seperate the two battery banks. The BIRD (right next to the Trombetta in the picture) tells the Trombetta when to open and close based on the voltage readings from the batteries. According to the Trombetta guy I spoke with the Trombetta almost never goes bad. It is just a simple relay. If anything hoes bad it s the BIRD or (more likely) the connection of the BIRD to the batteries.

Thanks, that's what I was seeing from diagram.

It's a nice setup, and quite different from very old motorhomes that essentially had a manual switch in place of isolator relay. In those days the owner made decisions instead of the BIRD, which could lead to making mistakes.

I like the automation, but don't know about the added complexity. One thing that is an improvement compared to previous systems like I had is the higher charging voltage, and also being able to charge the engine battery off converter or inverter/charger when 110-Volt is available.

Thanks again for clarification.

[Chance]

Originally Posted by Oneilkeys

In this diagram, the Trombetta is the isolator relay. It is connected in this generic diagram thru the two disconnect switches for the house and chassis battery. But it does not have to be hooked up this way. You can also see the five wires coming off the bird. I believe mine only has four. One power, ground and one to each battery.

Does that mean you don't have the auxiliary engine start?

[Oneilkeys]

Originally Posted by Chance

Does that mean you don't have the auxiliary engine start?

The diagram is generic. The aux start switch is in there somewhere to hook the two battery banks together and bypass the BIRD and Trombetta. I don't know exactly how Thor hooks it up and I wasn't interested enough to ask. As long as it works when I push the button I am happy. The one in my first Vegas did not. That was one of many warrantee items in 2014.

[Oneilkeys]

Originally Posted by Chance

Thanks, that's what I was seeing from diagram.

It's a nice setup, and quite different from very old motorhomes that essentially had a manual switch in place of isolator relay. In those days the owner made decisions instead of the BIRD, which could lead to making mistakes.

I like the automation, but don't know about the added complexity. One thing that is an improvement compared to previous systems like I had is the higher charging voltage, and also being able to charge the engine battery off converter or inverter/charger when 110-Volt is available.

Thanks again for clarification.

When you look how the system actually works, it isn't really that complex. The Trombetta is a simple open/close relay and the BIRD is an isolator relay that opens and closes the Trombetta based on the voltage it is receiving from the two battery banks. I talked to the people who build the Trombetta and BIRD when I was trying to figure out how Thor miswired mine and everyone I asked told me that both components are very reliable. The problem almost always is in the wiring. In this case the added complexity makes life simpler and probably more reliable. I think you are right. There is more chance for the user to make a mistake without the system than the chance that the system will malfunction.

[Chance]

Originally Posted by Oneilkeys

The diagram is generic. The aux start switch is in there somewhere to hook the two battery banks together and bypass the BIRD and Trombetta. I don't know exactly how Thor hooks it up and I wasn't interested enough to ask. As long as it works when I push the button I am happy. The one in my first Vegas did not. That was one of many warrantee items in 2014.

My 2 cents....

The diagram of the BIRD does not look generic to me, at least for that particular model. All wires to the microprocessor have to be installed in the right location or it won't work as intended.

I agree the wiring is simple. There is one wire from chassis to measure engine battery voltage. Another wire from house battery is used to measure that battery voltage and also appears to supply BIRD power. Another wire is output to fire isolator relay when needed. There is the ground. The fifth wire is a auxiliary engine start in case the chassis battery is dead and house batteries are good enough to start the engine. That wire should force microprocessor unit to bypass most or all program logic in order to jump-start the engine.

[Oneilkeys]

Originally Posted by Chance

My 2 cents....

The diagram of the BIRD does not look generic to me, at least for that particular model. All wires to the microprocessor have to be installed in the right location or it won't work as intended.

I agree the wiring is simple. There is one wire from chassis to measure engine battery voltage. Another wire from house battery is used to measure that battery voltage and also appears to supply BIRD power. Another wire is output to fire isolator relay when needed. There is the ground. The fifth wire is a auxiliary engine start in case the chassis battery is dead and house batteries are good enough to start the engine. That wire should force microprocessor unit to bypass most or all program logic in order to jump-start the engine.

Right. Mine is a 4 wire BIRD without the aux engine start. Thor wired it separately for some reason. By generic, I meant not necessarily like the installation in the Axis.

[bevedfelker]

Here is the BIRD wiring diagram Thor sent me. It has the emergency start switch. And I was wrong saying there was 2 Trombetta. There is only 1 and it feeds the two disconnect relays.

[bevedfelker]

Someone had asked what the Trombretta looked like and where it was located. Here is a pix of my 2015 Vegas 24.1. The device with the upside down lettering is the BIRD. If you look closely is says "Potted BIRD." Potted means it is sealed with a mastic material to keep water from getting in.

The device with the red connections is the Trombretta (isolation relay). It is called Trombretta because that is the company that makes it.

This is located in the engine compartment just a little below the oil dipstick.

[Chance]

Originally Posted by bevedfelker

Here is the BIRD wiring diagram Thor sent me. It has the emergency start switch. And I was wrong saying there was 2 Trombetta. There is only 1 and it feeds the two disconnect relays.

The four-wire version appears to be wired the same except that the auxillary engine start bypasses the BIRD entirely. Depressing the button (on dash?) will send house battery current directly to isolator relay. This seems to me a little simpler and more positive than the 5-wire version.

[Vinster30]

Waiting for my new BIRD and isolated relay (solenoid) to arrive tomorrow. Replacing both to be sure I correct my problem in one shot. THOR believes it is the BIRD, however, after playing with the relay, I am not convinced that it is not bad also.

Discovered that the alternator was not charging the house batteries when driving. The leveling system would show "low voltage" unless on shore power or generator. The converter is charging the house batteries.

Purchased the relay in the diagram above, that is a Intellitec brand. The supplier I used for the BIRD does not carry the Trombetta brand.

Will post results after the week end and maybe knowledge on which unit was bad.

[Oneilkeys]

Originally Posted by Vinster30

Waiting for my new BIRD and isolated relay (solenoid) to arrive tomorrow. Replacing both to be sure I correct my problem in one shot. THOR believes it is the BIRD, however, after playing with the relay, I am not convinced that it is not bad also.

Discovered that the alternator was not charging the house batteries when driving. The leveling system would show "low voltage" unless on shore power or generator. The converter is charging the house batteries.

Purchased the relay in the diagram above, that is a Intellitec brand. The supplier I used for the BIRD does not carry the Trombetta brand.

Will post results after the week end and maybe knowledge on which unit was bad.

I hope it solves your problem. Before you disconnected the BIRD, did you check and see what voltage it was receiving? When I checked mine, I found that the voltage being fed into the BIRD (supposedly from the house batteries) was different than the house batteries. I don't know what the BIRD was hooked to, but it was not the house batteries. When I hooked the wire to the house battery side of the Trombetta, everything worked normally.

[Ag&Au]

Thinking about this thread reminded me how complicated some things that should be really simple have become.

In the mid 1970s, I had a Chevy 3/4 ton pickup with a 11 ft camper in the bed. The camper originally shared the truck battery (mainly for a few lights), an idea that did not seem too good to me. I bought a battery and a box and mounted it beside the camper in the truck bed. I then purchased, at an auto parts store, a starter relay (solenoid) for an old car. I wired it to the ignition circuit so that whenever the ignition was on the relay was closed. So the alternator (it may have been a generator back then) charged both batteries. But when ignition was off, they were totally isolated. There were no trombones, coronets, birds or other animals involved. If I should ever leave the lights on (etc) in the truck, I carried a small jumper wire to connect the solenoids coil to the house battery, This then closed the relay and allowed the house battery to start the truck.

I also carried a battery charger and jumper cables for worst case scenarios. I still do that.

Why are today's systems better? To me it just seems way more complicated.

All I can see is that is takes the human out of the operation and thus the human hasn't a clue what is going on unless he is a musician who belongs to audubon so he knows about trombones and birds.

I'm guessing a trombetta is an in-development trombone that is still in beta mode.

Ken

[Chance]

Originally Posted by Ag&Au

....cut....

Why are today's systems better? To me it just seems way more complicated.

....cut....

Ken

Ken, did your 1970s camper have electrically operated slides, levelers, microwave, residential refrigerator and three televisions?

People's idea of "camping" has changed a lot. Roughing it is no longer as much fun.

Today's RVs are so much more involved that they require a lot more power. And to make matters worse, the average owner can't fix many things themselves. This all leads to costly repairs and time in the shop.

[bevedfelker]

The BIRD,, Trombretta, and Isolator relays also monitor when the batteries are fully charged so that they can also isolate the charging current to keep from over charging the batteries.

[scrubjaysnest]

Originally Posted by bevedfelker

Scrub -- you need to get yours checked because something is not working correctly (probably the Trombetta for the chassis battery).

The RV has two sources of power to charge chassis and coach batteries -- engine driven alternator (when driving down the road) and the charging circuit of the converter (when connected to shore power or when the generator is running).

The BIRD work in conjunction with two Trombrettas (one for chassis battery, one for coach batteries). The BIRD basically monitors both battery banks and when the voltage drops indicating one of the banks needs charging, it signals the corresponding Trombretta to close sending charging voltage to the battery bank needing charging. When the battery bank is fully charged, the Bird will signal the Trombretta to open and isolates the battery so it doesn't overcharge.

The converter's charging circuit should provide trickle charging to the chassis battery when you are on shore or generator power. The BIRD would detect when the chassis battery voltage is below fully charged, then it signals the Chassis battery Trombretta to close sending power from the converter to the chassis battery to top off its charge.

There have been several folks on the forum find out that their Trombrettas were not wired correctly. In essence, the house and chassis batteries should be receiving charging voltage from wither the converter or the engine driven alternator depending on need.

This interlay of charging voltage sources, BIRD, and Trombrettas is why I called this thread "What Charges the House and Chassis Batteries When." when I first posted it.

Since we primarily dry camp and charge off solar I'll be digging into to entire system. Should be a piece of cake for a retired electronics engineer.

There are several areas that need attention in my opinion. The dash radio/camera monitor should not be powered off the house batteries. An on/off switch for the dash radio to kill that drain when not in use.
The chassis battery doesn't need to charge off the solar system normally for a week or two stop.
Change out the 8955 convertor for one that will produce 14.8 volts during the absorb stage when on shore power even though for us that is less then 5% of the time.
Upgrade the house batteries to a known brand so proper charging curves can be programmed into the solar charge controller.

[Oneilkeys]

Originally Posted by bevedfelker

The BIRD,, Trombretta, and Isolator relays also monitor when the batteries are fully charged so that they can also isolate the charging current to keep from over charging the batteries.

True Ed. And they also isolate both banks on startup so that if your house batteries are way down, they will not draw down the chassis battery so that you cannot start your RV. Only when the alternator is putting out full power does the BIRD close the Trombetta to charge the house batteries. While it adds complexity, it also simplifies your daily operation. And if the system does not work the two posts of the Trombetta are 2 inches apart with cables leading to both battery banks. A 6 inch jumper cable will physically connect both batteries. Or, in a pinch, if you do not have a jumper cable, you could just disconnect the wire from one Trombetta post and put both wires on the same post or join them with a bolt bypassing the Trombetta.

[bevedfelker]

One reason the dash radio (at least in 2015 models) is powered by the coach batteries is so that you can run the radio while camped and not run down the chassis battery. That is also why they included the radio remote so that you can turn off the radio and adjust the volume from the bedroom.

In my 2015 Vegas the coach batteries provide power to operate the radio; however, the power for the radio's preselect stations and radio clock comes from the chassis battery. I suppose that is because when you set the USE/STORE to Store and disconnect the coach batteries you would wipe out the radio's preselect stations and turn off the clock. Every time you'd repower you would have to rest the clock and preselect stations.

[Ag&Au]

Originally Posted by Chance

Ken, did your 1970s camper have electrically operated slides, levelers, microwave, residential refrigerator and three televisions?

People's idea of "camping" has changed a lot. Roughing it is no longer as much fun.

Today's RVs are so much more involved that they require a lot more power. And to make matters worse, the average owner can't fix many things themselves. This all leads to costly repairs and time in the shop.

Now that I think about what we did when my kids were growing up, and what I did when I was growing up, one of the purposes was to avoid most of those thing you mention. I guess modern camping is all about bringing as much of your home with you as possible to a different location. Not that I'm doing any differently, and at my age I would not want to go back, but somehow a lot of the fun and adventure has gone out of it.

In any case, sorry for the distraction. Let's get back to how to fix all the neat stuff we now have, and aren't sure how works, or what it does.

Ken