Battery voltage drops

[Falcon]

2019 3791RD, 20th anniv. edition: While boondocking, we experienced a slow loss of voltage over days. Each morning the PV panel seemed to bolster things but each day it was less. I have two Honda 2000i's, paralleled, I'm told is worth 26.2 amps (one AC unit and the microwave trips them out). I ran these for hours without any increase in battery voltage. I hooked up the trailer wire to the truck and ran it for an hour, no increase. But days earlier, when hooked up to shore power at a park, the battery voltage went right up to 13.9. But I'm reading this from a digital gauge on the outside of the control panel cabinet. I'm not even sure what I'm reading. Is this the real voltage from the batteries? Is this how much the PV panel is putting out? is it something else all together? It has a logo on it that matches the PV panel system logo. When voltage runs low, there is a curious sound in between the ODS pass-through storage front panel and the battery compartment. I recorded it on a phone video but can't attach it (it's an mpeg). It's a sharp click, then a crackling sound, then a "boing" like you plucked a string. It's about 3 seconds for the three sounds, then repeats about 6 seconds later. Any help or experience is most welcomed.

[masterdrago]

Click, crackling, boing... I'm watching this thread

[Falcon]

I know, right! Can I send you the file? email or something?

[Carl n Susan]

Running the Hondas is indistinguishable from normal shore power to the Montana. You need to check the voltage at the battery. I suspect it is 12.something. If it is the same when you run the Hondas, get into the battery compartment and listen to the left hand 50 amp self resetting circuit breaker. I bet it is the source of the noise. Check the voltage on the Load side when the gennies are running and it should be 13.something. You can jumper the 50 amp CB while waiting for a replacement (hopefully an 80 amp one).

[Falcon]

Originally Posted by Carl n Susan

Running the Hondas is indistinguishable from normal shore power to the Montana. You need to check the voltage at the battery. I suspect it is 12.something. If it is the same when you run the Hondas, get into the battery compartment and listen to the left hand 50 amp self resetting circuit breaker. I bet it is the source of the noise. Check the voltage on the Load side when the gennies are running and it should be 13.something. You can jumper the 50 amp CB while waiting for a replacement (hopefully an 80 amp one).

That is very valuable information. I have read elsewhere about upgrading this breaker. Any info on a source?

[Carl n Susan]

This post should help you find an 80 amp breaker.
https://www.montanaowners.com/forums...ad.php?t=70303

[Falcon]

Originally Posted by Carl n Susan

This post should help you find an 80 amp breaker.
https://www.montanaowners.com/forums...ad.php?t=70303

In this thread, they talked about replacing the breaker for the hydraulic system. If this is the same process for the Trailer Load breaker on the left, then no problem I can proceed. Are both the breakers 50 amp originally?

[Carl n Susan]

Yup, same breaker. The usual failure is the draw by the hydraulic pump. But the other big red wire is the feed to the 12V fuse panel and the line the converter uses to charge the batteries.



Both CB were 50 amp to start. Onlt the left one has caused problems. The right one has lesser draw circuits.

[Falcon]

Thank you so much, Carl & Susan, priceless info. The breaker is ordered. Bless you.

[beeje]

I installed a LCD meter below the switch panel that reads the battery voltage 24/7. Sitting idle for a while it always reads around 13.3. Upon returning home from a trip and plugging back in it reads 14.4 or so for awhile. I walk by it many times a day and would notice an issue right away

[oddjobal]

My problem was caused by a bad 12v converter (replaced). I know different problem. In my feed through compartment the is a 12v connector. I put a small LED panel meter and connected it to the circuit. When I have let my rig sit for a while and plug it in, it goes to 13.9 till the batteries are charged. After a while of charging it drops to normal battery voltage. I do this instead of hunting all over for my meter. Mine is an older smaller rig. But this is a quick at a glance item for around $10

[MJohnston]

I agree with the recommendation to replace the 50 amp CB. I did that right after having the hydraulic trip problem (I live in Colorado) and it fixed the problem.
In regards to your charging problem, its likely a CB problem given the snap, crackle, pop sounds you described. However, you might also make sure the red battery key that isolates your batteries is in the “On” position as well. Its located in the water bay area. You likely already confirmed this, but just making sure.

[bcrvman]

Originally Posted by Falcon

2019 3791RD, 20th anniv. edition: While boondocking, we experienced a slow loss of voltage over days. Each morning the PV panel seemed to bolster things but each day it was less. I have two Honda 2000i's, paralleled, I'm told is worth 26.2 amps (one AC unit and the microwave trips them out). I ran these for hours without any increase in battery voltage. I hooked up the trailer wire to the truck and ran it for an hour, no increase. But days earlier, when hooked up to shore power at a park, the battery voltage went right up to 13.9. But I'm reading this from a digital gauge on the outside of the control panel cabinet. I'm not even sure what I'm reading. Is this the real voltage from the batteries? Is this how much the PV panel is putting out? is it something else all together? It has a logo on it that matches the PV panel system logo. When voltage runs low, there is a curious sound in between the ODS pass-through storage front panel and the battery compartment. I recorded it on a phone video but can't attach it (it's an mpeg). It's a sharp click, then a crackling sound, then a "boing" like you plucked a string. It's about 3 seconds for the three sounds, then repeats about 6 seconds later. Any help or experience is most welcomed.

The truck wiring is too small to do any real charging. I use the same Honda's with no problem. I assume you are using a 50 to 30 dogbone that plugs into the Honda A unit that is then jumpered with special wires supplied by Honda to the B unit. By now you should know you need and are using a bonding plug as well. Highly recommend using a Trimetric TM2030-RV, voltage is not a reliable way to measure a battery. Did you upgrade your stock junk batteries to Trojan T105's or similar?

[Bill M]

Read voltage off your inverter if turned on.

[masterdrago]

I added a repeater (TPMS) switch and one to read the vdc to a display in the propane compartment over the battery box area. When they are not needed, I can turn both off.

[bcrvman]

Originally Posted by Bill M

Read voltage off your inverter if turned on.

I think what Bill meant was converter, an inverter turns DC into AC. When you do this, disconnect the battery cable and measure voltage of the converter leads and after an hour measure the battery. You have to let a battery 'settle' to get an accurate reading.

Keep in mind an RV converter is designed for a system where you are always plugged in and its job is to simply act as a trickle charger.

[Buckfisher]

Bcrvman hit the nail squarely on the head. Running the generator and charging the batteries using the RV's converter will take a long time. Especially if you're using 12 volt power at the same time. They will charge much faster if you plug in a battery charger to charge the batteries. I dry camped while building my home for a few months. Been there, done that.

[bcrvman]

Originally Posted by Buckfisher

Bcrvman hit the nail squarely on the head. Running the generator and charging the batteries using the RV's converter will take a long time. Especially if you're using 12 volt power at the same time. They will charge much faster if you plug in a battery charger to charge the batteries. I dry camped while building my home for a few months. Been there, done that.

There is a trick however if you have the right kind of converter. The Progressive Dynamics brand has a flashing LED and a tiny button beside it. Check your owners' package for Converter docs and press the button to cause the converter to deliver 14.4 volts or close. HOWEVER you have to manually turn it off as well or you will boil your batteries dry. It can take 4+ hours so it isn't super critical but set a timer and turn it off after 4 to 6 hours. By off I mean 13.6 Volts. Your docs should tell you what LED patterns equate to which voltages. If you have another brand, you will need to see if it has something similar, otherwise by a dedicated 75 amp to 100 amp charger.

[Bill M]

If you have a residential refrigerator then the inverter will read your dc voltage. This is also a great way of checking if tow vehicle is charging battery while traveling.

[Carl n Susan]

Even more available is the voltage display in the Level Up system. Pretty much everyone has one of those now a days.