Battery Charging Question ???

[TimmyB]

Originally Posted by Oneilkeys

The easiest place to check the voltage on your chassis battery is using the left hand post of the Trombetta. Put your positive lead on the list and the negative on unpainted chassis. The right hand post will give you the charge on the coach batteries. (They could be reversed on yours.) It is an easy way to see if the Trombetta is open or closed. Open and both voltages will be the same. Closed and they won’t.

Yeah, I had read that this weekend, but wasn't really sure what I was looking at. I'll try it again in the morning.

Thanks!

[JoeDS]

Originally Posted by sandrooney

I am sure this has been beat to death. I have a 16 Axis 25.2. I did a search on this and am getting conflicting answers. Does the chassis battery charge when plugged into shore power or off the generator. Does the chassis alternator charge the house battery's as well as the chassis battery?
Thanks a lot,
Kevin

Yes and Yes. When its working properly!

[sandrooney]

Thanks. I got mine figured out. My chassis battery was bad. Replaced and all is good now.

[TimmyB]

Originally Posted by Oneilkeys

The easiest place to check the voltage on your chassis battery is using the left hand post of the Trombetta. Put your positive lead on the list and the negative on unpainted chassis. The right hand post will give you the charge on the coach batteries. (They could be reversed on yours.) It is an easy way to see if the Trombetta is open or closed. Open and both voltages will be the same. Closed and they won’t.

So, I've been a little busy but finally had a chance to do some electrical snooping today. This is a picture of my Trombetta relay. This is how it is actually oriented, with Battery A on the top and Battery B on the bottom. From top to bottom on the smaller three posts, IGN (Ignition?), G (Ground?), and Sig (Signal?). If you wouldn't mind, could you (or anyone) explain to me what I am looking at and how to use this to check the voltage of my chassis battery?

Thanks for your assistance!

EDIT: For whatever reason, the picture is rotated 180 degrees from the way it appears on my computer. The larger, red coated terminals are actually coming in from the left, not the right.

[16ACE27]

That is a PRECISION CIRCUITS BATTERY ISOLATION MANAGER 160 AMP RATED.

You can measure the voltage of each battery from it's associated red cable to ground with a voltmeter.

Here's a PDF that explains it:

http://www.precisioncircuitsinc.com/...ger-Rev7-1.pdf

[TimmyB]

Originally Posted by 16ACE27

That is a PRECISION CIRCUITS BATTERY ISOLATION MANAGER 160 AMP RATED.

You can measure the voltage of each battery from it's associated red cable to ground with a voltmeter.

Here's a PDF that explains it:

http://www.precisioncircuitsinc.com/...ger-Rev7-1.pdf

Yep, that was the help I needed! Thanks!!!

[bevedfelker]

No one mentioned the kicker -- the house batteries WILL NOT charge unless the USE/STORE switch is in USE. So yes, the engine alternator will provide current to charge the house batteries. Without getting too complex there is either a BIRD/Trombetta system or a Battery Control System that will monitor the charge state of the chassis battery and also the house batteries. Automatic circuity in either of those two systems I mentioned will isolate the battery(ies) that require charge. The system will go back and forth charging the battery that needs the charge.

But again central to charging the house batteries is that USE/STORE switch. When that switch is in STORE the house batteries are electrically isolated; therefore, no charge can get to it. In USE a relay is engaged to connect the house batteries to the converter from where the current comes to charge the batteries.

I attached a file that explains how the BIRD & Trombetta work together to keep the chassis and house batteries charged. If you have a Battery Control Center instead of BIRD & Trombetta it works exactly the same way . It's just that all the relays are built into the Battery Control enter.

[TimmyB]

Originally Posted by bevedfelker

No one mentioned the kicker -- the house batteries WILL NOT charge unless the USE/STORE switch is in USE. So yes, the engine alternator will provide current to charge the house batteries. Without getting too complex there is either a BIRD/Trombetta system or a Battery Control System that will monitor the charge state of the chassis battery and also the house batteries. Automatic circuity in either of those two systems I mentioned will isolate the battery(ies) that require charge. The system will go back and forth charging the battery that needs the charge.

But again central to charging the house batteries is that USE/STORE switch. When that switch is in STORE the house batteries are electrically isolated; therefore, no charge can get to it. In USE a relay is engaged to connect the house batteries to the converter from where the current comes to charge the batteries.

I attached a file that explains how the BIRD & Trombetta work together to keep the chassis and house batteries charged. If you have a Battery Control Center instead of BIRD & Trombetta it works exactly the same way . It's just that all the relays are built into the Battery Control enter.

Problem with that is, the red light on the USE/STORE switch lies to us! At least, mine does. When plugged in to SP, the red light comes on, REGARDLESS of the state of the switch. I can be plugged in to SP all day long and have the red light on, thinking that my house batteries are being charged, when they are not. I must watch the voltage reading in my solar power connector beneath said switch to determine if the switch is really "on" and allowing the batteries to be charged, or not. If I press the switch while plugged in to SP, the red light will stay on, but the voltages will alternate between whatever charge the battery currently has (12.4-ish, switch is off) and whatever the batteries are receiving from their external source (13.7-ish, switch is on). That is not good, imo. If that red light is on, that should mean that my 12V system is running and the batteries are being recharged.

[petefoss]

Agree but that's the way my 31W is wired too. I use the inverter voltage display to verify the switch position. Plus u also have the situation where the chassis battery is not charged by shore power, so I plug a battery minder in to an outlet in the coach and feed the 12V connector on the dash while in storage.

[Bill Barber]

Thanks so much for your information, now I know what to do from now on 👍👍

[bgpeters]

It happened to me too. On Shore power, but the disconnect switch was on 'store'. Opps. EVERYTHING drained down so low nothing worked. The chassis battery SHOULD have been isolated from the house batteries by the Precision Circuits Battery Isolation Manager (BIM 160), but it wasn't so EVERYTHING is kaput.

I think I need to install a new BIM 160, since it is not actually isolating the chassis and house batteries. It seems to always have them connected as far as I can tell.

When not connected to Shore power the disconnect switch make great sense to shut off everything that uses 12v. I use it religiously.

I see the WFCO WF-9855 55 Amp Converter output connected to the Intellitec Battery Disconnect (operated by the storage switch), from the switch the line goes to the house batteries. If the Converter is on at all, then there's boat loads of power available for charging. Why not let the Converter line go direct to the batteries (maybe with a diode?). Why go through the disconnect at all?

[Oneilkeys]

It is easy to check before you buy a replacement BIM. Buy a cheap volt meter instead and check both batteries (house and Chassis) after everything is turned off. If they are different voltages, the BIM is disconnecting the batteries, turn on the engine and the batteries should read the same after a few minutes. The chassis battery may drain by itself. There are parasitic loads on it too.