Community Forums

bamaboy473 · 12-11-2020, 01:01 PM

I'm trying to find a cause for the house batteries not being charged by the alternator, but are charging fine with the genset and SP. The first guy at the shop (truck shop that does it all) asked whether any coach charges house batteries while driving down the road?

My view is that if the batteries are inverting to power what we use during the trip, they need to be charged, so the alternator should be charging them.

Can somebody confirm this so I don't make a mis-statement to him?

Following that, I've done a soft and a hard re-set on the Magnum 2812, to no avail. Anybody have any ideas? Voltage from the alternator is round 14V.

House and starting batteries are less than 6 months old.

Pillbox · 12-11-2020, 01:06 PM

Bird, white rabbit.
Fuse, or bad relay.
House batteries switch turned off in battery bay.

bamaboy473 · 12-11-2020, 01:31 PM

Quote:

Originally Posted by Pillbox

Bird, white rabbit.
Fuse, or bad relay.
House batteries switch turned off in battery bay.

The shop will look for reasons why the batteries are discharging quickly, whether the battery switch is ON or OFF in the bay.

Do your batteries charge while you're driving down the road?

Pillbox · 12-11-2020, 01:45 PM

Yes, all do. House and chassis.
Does your battery boast work?
Check voltage on house batteries, vehicle off, note voltage.
Check voltage on chassis batteries, again, note voltage.
Start vehicle, wait 1 to 2 minutes, check voltages again
Chassis should be about ~14,
House should also go up, but only when the chassis battery is happy. Too much alternator voltage output ie ~15 volt or more, will fry the alternator.
The chassis batteries get first charge, then house gets whats left, on mine 13.0 or more.
If you have some help, have someone start the vehicle, you stand by the battery tray and you should here the relay CLICK. Thats when both are getting charged. It takes 1 to 2 minutes, for the click.

Dennis429 · 12-11-2020, 01:47 PM

Mine do charge when driving down the road. It did not then what is the since in having them you would have to run the generator all the time to charge them.

Pillbox · 12-11-2020, 01:58 PM

This is out of your manual

777 Driver · 12-11-2020, 02:01 PM

Here's a link to a description of the BI-DIRECTIONAL ISOLATOR RELAY DELAY (BIRD):

https://www.mikerobotics.com/Intelli...300839.000.pdf

That .pdf gives an excellent description of how your batteries should be charging from your alternator, generator or shore power. It also gives troubleshooting for various failures, including:

Coach battery not charging from engine.

Check for open circuit breaker to coach battery. With engine running, chassis voltage should be above 13.5 volts. If less than 13.1 volts, check vehicles charging system.

Check ground on module.

Check for voltage on coil of isolator relay after engine has been running for at least 3 minutes. Voltage should be approximately 12 Volts. If no voltage, replace BIRD.

If 12 volts is applied to isolator relay coil, check for voltage drop across the isolator relay contacts. If the drop is greater than 0.2 volts, replace relay.

Good luck.

Take care,
Stu

Pillbox · 12-11-2020, 02:09 PM

Dont know what you got, but here are some different ones.

Gary RVRoamer · 12-11-2020, 03:09 PM

In 99.9% of motorized RVs, it works like this:

When the engine is running, a relay closes to connect the house battery bank to the chassis batteries, allowing the alternator to charge both. In some coaches there is a smart device to manage when that relay closes, while in others it just gets closed whenever the ignition switch is in the ON position. Your Eagle is in the smart group, probably using an Intellitec Battery Control Center (BCC) to manage it. The BCC closes the isolator relay only after it senses that the chassis batteries have reached a full charge. The Intellitec BCC considers a battery voltage of 13.3 to be full charge.

If yours isn't charging the house bank while the engine is running, the possibilities are:

1. Chassis batteries are weak and not reaching the 13.3v threshold
2. BCC is faulty and not doing its job commanding the relay to close
3. The isolator relay is faulty and not closing
4. The cable connections from chassis battery to BCC to relay and on to the house batteries are falty somewhere along the line.
5. The house battery disconnect switch is set to Off (Disconnect), preventing charging voltage from reaching the batteries.

dfuelman · 12-11-2020, 03:10 PM

I was having similar issue with my Country Coach except in reverse. Chassis Battery would not charge on Shore power. My issue was the echo charger had a blown fuse on the chassis side. Echo charge passes current from strongest battery to the weakest to keep both fully charged. It only has three wires, One is a ground, and two leads, one to each battery that are fused. If one fuse blows, system does not work. Something to look into. Should be located near your inverter and batteries, black box approx 10" square.

bamaboy473 · 12-11-2020, 05:16 PM

The coach is at a truck service center for some things and the batteries are all less than 6 months old. I'm going to show the service guy (who is not familiar with motor homes, per se, this thread since he knows what you're talking about more than I do.

Quote:

Originally Posted by Gary RVRoamer

In 99.9% of motorized RVs, it works like this:

When the engine is running, a relay closes to connect the house battery bank to the chassis batteries, allowing the alternator to charge both. In some coaches there is a smart device to manage when that relay closes, while in others it just gets closed whenever the ignition switch is in the ON position. Your Eagle is in the smart group, probably using an Intellitec Battery Control Center (BCC) to manage it. The BCC closes the isolator relay only after it senses that the chassis batteries have reached a full charge. The Intellitec BCC considers a battery voltage of 13.3 to be full charge.

If yours isn't charging the house bank while the engine is running, the possibilities are:

1. Chassis batteries are weak and not reaching the 13.3v threshold I'll check their voltage after charging them with the genset, but they are less than 6 months old, too.
2. BCC is faulty and not doing its job commanding the relay to close
3. The isolator relay is faulty and not closing
4. The cable connections from chassis battery to BCC to relay and on to the house batteries are falty somewhere along the line. Maybe, but no corrosion and all were cleaned within the past 6 months
5. The house battery disconnect switch is set to Off (Disconnect), preventing charging voltage from reaching the batteries. Set to ON while charging, but losing voltage when swithc is ON or OFF

The house batteries are draining power whether the main switch is ON or OFF, which may be another symptom? There is nothing in the coach that's running, so it's another mystery.

twinboat · 12-11-2020, 06:35 PM

Quote:

Originally Posted by dfuelman

I was having similar issue with my Country Coach except in reverse. Chassis Battery would not charge on Shore power. My issue was the echo charger had a blown fuse on the chassis side. Echo charge passes current from strongest battery to the weakest to keep both fully charged. It only has three wires, One is a ground, and two leads, one to each battery that are fused. If one fuse blows, system does not work. Something to look into. Should be located near your inverter and batteries, black box approx 10" square.

That's not what a Echo charger does. It only charges the chassis battery from the house battery, If the house battery is being charged by its charger.

You will still have a isolator or isolation solenoid for chassis to house charging.

twinboat · 12-11-2020, 06:39 PM

Quote:

Originally Posted by bamaboy473

The coach is at a truck service center for some things and the batteries are all less than 6 months old. I'm going to show the service guy (who is not familiar with motor homes, per se, this thread since he knows what you're talking about more than I do.

The house batteries are draining power whether the main switch is ON or OFF, which may be another symptom? There is nothing in the coach that's running, so it's another mystery.

On many RVs the main battery switch does not turn off the inverter/charger. If the inverter us left on, it will draw down your house batteries.

153stars · 12-11-2020, 07:27 PM

To add to above the detectors, LP solenoid if equipped , fridge and LP water heater 12v lp valves. The inverter will use much more if it's on than those. Mine has charge only setting switch, if I loose charging AC while stored won't run down batts. It seems to bulk charge higher when needed and set to charge only as well.