No DC Power after shutting down generator

[rvpep]

Hello all,
2023 Momentum 25G ,No DC power inside coach, electric jack has power. It started with my 12V Refrigerator chirping from low voltage 11.2 V. I started the generator and ran for 45 minutes after bringing the voltage up to 12.7 or so. When the generator shut down I had no DC Power in the coach. On shore power all DC works. 2000w inverter works regardless. Batteries have been plugged in and charging 12 plus hours; they're at 13.3V (lifepo4). And still no DC power.

I started testing from the battery back. Continuity was good on both inline 30A circuit breakers(frame mounted) and all fuses. Battery disconnect is on. I tested the battery dc in both positions. Inside: Panel:110 side no circuit breakers were not tripped, all fuses on DC side are good.?

2023 Momentum (less than a month old) 2- 100ahr 12V Battleborns, 660 W Solar Panels,50A mppt solar controller, WFCO WF8955 AD Converter. All factory or dealer install.

Any advice would be greatly appreciated,
???????Thanks in advance.
?

[Grit_dog]

rvpep wrote:
In-line 20A Fuse was removed and replaced with a butt connector. The dealer with advice from GD performed the work under warranty. This 20A online fuse was a mistake at the factory.

Thank you for actually following up on this. That is helpful for those that may use this for more than just entertainment purposes.

[CA_Traveler]

Contact the mfg and make sure. Fuses are sized to protect the wires from over heating and causing related problems. What's protecting the wiring now?

I would measure the DC amps and wire size to be sure the lack of a fuse is the correct choice.

Yes I'm skeptical of dealers and mfg and suggest you should also be also. Their primary goal to often is for problems to exceed the warranty. And when it doesn't warranty repairs are often low priority.

[rvpep]

In-line 20A Fuse was removed and replaced with a butt connector. The dealer with advice from GD performed the work under warranty. This 20A online fuse was a mistake at the factory.

[rvpep]

I talked with a tech at WFCO regarding this issue. He is 99% sure that the 20A inline fuse is to small. He recommends installing and testing a 50A in its place. The 8 awg wire is rated for 60A and goes from the battery to the Power Dist. Panel/55A converter. Can anybody with a 2022 Grand Design Momentum G classc or older check and confirm there DC fuse size and report back please ? Thanks

[pianotuna]

rvpep,

Glad you found the issue. Consider moving to an autoreset breaker for that fuse.

[MrWizard]

Finding the problem is good news, 20 amps sounds small for all the DC power in the coach,

[rvpep]

Found the culprit. It was a 20A Fuse in the inverter compartment, one of the first places we checked. We assumed it was a fuse for the inverter and moved to the underside to test all breakers ,big fuses and battery disconnect switch. Oh well, live and learn. The bottom line is I need to know where my battery Amps are before I run something like a Kuerig. (I hear Kuerig is german for Rig Killer). I will follow up and try to determine exactly what caused this and report back. Victron bmv712 and Progressive Dynamics Converter will be coming soon.Thanks for all your help.

[MrWizard]

What is the voltage at the batteries, does your system have a low voltage cutout between the battery and the control box? Unusual but possible, what is between converter which is using shore power and working, and your batteries, both sources of 12v power should be connected to the control center, there is a break in the circuit some place, like possibly the battery disconnect relay, these latch in position wether on or off, it's in the off position either its stuck, or the on off switch is not supplying the on signal, that relay Should be in the control center, if it's not, you need to find it

[CA_Traveler]

BTW Since you think it's the battery install a 12V car battery and post the results.

[CA_Traveler]

From what you've posted with the inverter working on battery only, the battery is not the problem. Sure it may be partially discharged but more than adequate for say lights. Do you have a voltmeter? if not buy a $20 one from harbor freight and start checking as suggested.

There is more to wiring than breakers and fuses. Like corrosion, bad connectors, broken wires, unknown components, etc.

[AllegroD]

Do you have a combiner in the bay. While on shore/genny, try a screwdriverquick jump (across chassis/house) to "jump start" your BB BMS.

[rvpep]

Mr. Wizard, all breakers and fuses in the control center have checked out okay.

However there is no power to the 12vdc side unless on shore power. Coach on

shore power for almost 24 hours with no change. Batteries disconnected now and

charging on small lithium charger. Not trusting my auto detect converter to top

off/equalize the lifepo4's.

[MrWizard]

Since the inverter works,, the BMS and Battle Born Li Batteries are good, But not fully charged, i suspect there is a Tripped DC breaker in in the battery control center of your coach, this is a box between your batteries and house DC fuse panel, it has relays fuses and DC circuit breakers, it should be labeled, but it could be anywhere inside or outside

[stickdog]

If the battery was as low as you said, 45 minutes on the charger you got no more then a surface charge.