Battery Fluctuations and WFCO Unit Fault Codes

[hlhawthrone]

We have a 2023 Momentum 25G with two 300W factory installed solar panels and a WFCO WF-5220 inverter.

We have had to replace the 20amp fuse in storage compartment where inverter is located TWICE in the last month. Both times after shutting down inverter and ALL power becoming lost.

A mobile tech came out and tested the batteries/wiring and everything appeared to be working. He said to keep off shore power to see what happened. When he left on Thursday around 3pm, we unplugged from shore power. I have notes (included photo) of fluctuating battery voltages and times over the past 3 days. The only thing using power is the 12V fridge. Is this pattern normal?

Also, any idea why we received the “Env. OTP Shutdown” and “UVP Shutdown” unit fault codes when showing 12.6V? The unit is currently plugged into shore power.

Hoping the forum has some ideas before I call the mobile tech back on site.

[TucsonJim]

Hello,

I need to clarify a few things first.

1. What is that 20 amp fuse protecting and what do the wires power? BTW, wire nuts are not typically used to connect a fuse in a circuit since the fuse holder wires are stranded. Wago connectors would be much more reliable.
2. What type of batteries do you have, and how many? I see some of your recorded voltages are as low as 11.6 volts. On a lead acid battery, that is seriously depleted, and should never be allowed to go below 12.1 volts to protect the battery. Remember that current equals watts/volts. So if the voltage goes down, the current will go up and possibly blow a fuse.
3. When you recorded the voltages, did you turn off all power drains, including the refrigerator? In order to get an accurate battery voltage reading, all items should be powered off, and the batteries allowed to rest for five minutes before taking the reading.

Jim

[hlhawthrone]

TucsonJim
1- We are unsure what the fuse is for. We just upgraded to this trailer in April.
2- We have 2 lead acid batteries.
3- No we did not.

[Country Campers]

hlhawthrone

Could you please get a little better picture of those wires with the fuse, where do they go? What are they connected to?

Is this trailer new or used?

Brian

[TucsonJim]

hlhawthrone

Could you please get a little better picture of those wires with the fuse, where do they go? What are they connected to?

Is this trailer new or used?

Brian

Brian - They are the first owners. They aren't sure where the fuse is connected to.

hlhawthrone - It's going to be tough for us to help trouble-shoot this issue without being on site with a meter. The first thing I'd do is trace those wires the fuse is connected in order to understand what's wired where. Without knowing what it's supplying and how it's wired, we're at a loss.

Jim

[howson]

hlhawthrone
So this is a continuation of the fault documented in https://gdrvowners.com/forum/solar/1...nd-solar-power ???

[hlhawthrone]

Country Campers We purchased the trailer from the dealer as a NEW (2023 Momentum 25G). I included some additional photos. This is located in the outdoor storage. howson is correct. This is a continuation to another post https://gdrvowners.com/forum/solar/1...nd-solar-power. We took the trailer out boondocking for 4 nights last weekend. Each night the batteries got down to 11.1V; daytime it was at about 13.4V. We used the generator in the morning and evening to charge batteries along with solar. On the third day the fuse went out ofter shutting off the generator like it did previously. By the last night we were able to keep more power overnight by turning inverter and refrigerator off.

We had a mobile tech come out and he checked voltage and wiring with the voltage meter and everything seemed to be fine. It's over a few hours where the voltage drops - even when nothing is being used. They should be new batteries... but them dropping down below 12.1V consistently like TucsonJim mentioned is worrisome - especially on a newly purchased trailer.

[Country Campers]

Do those, or one of those, wires connect to the inverter?

I believe that those are the wires from the battery to the inverter. If the battery level gets too low the draw amps from the inverter will be higher thus blowing the fuse. When the generator shut off the automatic transfer switch switched to inverter and, if there were large draws like an AC running or microwave, I am guessing that the batteries were not charged enough and the fuse blew, maybe?

Brian

[TucsonJim]

Do those, or one of those, wires connect to the inverter?

I believe that those are the wires from the battery to the inverter. If the battery level gets too low the draw amps from the inverter will be higher thus blowing the fuse. When the generator shut off the automatic transfer switch switched to inverter and, if there were large draws like an AC running or microwave, I am guessing that the batteries were not charged enough and the fuse blew, maybe?

Brian

Agreed Brian. It's pretty apparent that low voltage is causing high current flow and popping the fuse. But I'm so curious what that 20 amp fuse is supplying in the first place.

Jim

[mgnuttall]

Country Campers We purchased the trailer from the dealer as a NEW (2023 Momentum 25G). I included some additional photos. This is located in the outdoor storage. howson is correct. This is a continuation to another post https://gdrvowners.com/forum/solar/1...nd-solar-power. We took the trailer out boondocking for 4 nights last weekend. Each night the batteries got down to 11.1V; daytime it was at about 13.4V. We used the generator in the morning and evening to charge batteries along with solar. On the third day the fuse went out ofter shutting off the generator like it did previously. By the last night we were able to keep more power overnight by turning inverter and refrigerator off.

We had a mobile tech come out and he checked voltage and wiring with the voltage meter and everything seemed to be fine. It's over a few hours where the voltage drops - even when nothing is being used. They should be new batteries... but them dropping down below 12.1V consistently like TucsonJim mentioned is worrisome - especially on a newly purchased trailer.

I have a 2022 Momemtum 25G also with the inverter prep, but no inverter. I have the same wiring shown in your photo with the 20 amp fuse, so I assume this is factory wiring. I have been confused about the fuse being a 20 amp fuse. I assume this fuse is feeding your inverter. If so, it seems too small to me. I am assuming you have a 1000W inverter installed. If so, on the AC side it would only give you a couple of amps capability with the inverter. The wire looks like number 10 which would allow a 30 amp fuse. I would expect a 1000 W inverter to be able to handle 60 amps on the DC side so I am surprised by the fuse size. Do you know what size your inverter is?

I am going to install a 2000 W inverter instead and have upgraded the AC side to 12 awg instead of 14 awg and am changing out the AC breaker feeding inverter to a 20 amp instead of the 15 amp. I am planning on replacing the DC wiring to the inverter with 2/0 wire and a 300 amp fuse.

[74barrio]

TucsonJim
2- We have 2 lead acid batteries.

What size are the batteries? Group 24? If so that might not provide enough battery storage for your trailer with a 12v fridge. I have a 23G with a 12v fridge, and I can easily use 60+ amps overnight, especially in the winter running the heater, until the sun comes back up and starts charging the batteries again (I have two 100AH lithium batteries). With two 300 watt panels you have plenty of solar, jut need more battery storage.

[bpep]

I had/have the same issue on my 2023 25G. As well as others. See https://www.facebook.com/groups/Gran...7186319209449/.
I have 2-Lifepo4 batteries,660W of solar. I believe the 8 awg wire with the 20A fuse goes from the batteries to the WFCO Power Distribution Panel and is for DC power. It is not connected directly to the inverter. I've dry camped for about 20 days total and this has happened twice. Both times on the third day with partly cloudy conditions. Voltage drops rapidly overnight (13V to 11.3V in about 7-8 hours). When starting the gen after this voltage drop there must be a power surge that blows the fuse. The fuse was partially melted and stuck inside the holder. I think the 12V fridge is the culprit. Until I figure this out with a smart shunt install I will be trying the following.
Before starting the gen after a big voltage drop. Shut off the 12V fridge and the inverter. HL Hawthrone make sure you let GD know so they can open a case.