AGM Replacement and Charging

kab449

Active Member
3160EL Bighorn with an Intelli-Power 9200 Power Converter 80amp output.
2 Replacement Batteries: Duralast 31-AGM 100amp hour.
Converter to Battery wire size 6awg
Automatic circuit breaker 50 amp

Problem: When the batteries are discharged to 50% and recharge starts the wire gets warm and the breaker goes into set/reset mode.
I am going to replace the automotive type circuit breakers with an 80 amp manual reset trolling motor circuit breaker. My question pertains to the wire size Heartland installed (6awg). According to the charts, 6awg is good for 100 amps up to 20 feet long. The manufacturer of the circuit breaker shows 6awg good for 60 amps only for a short distance but the circuit breaker is sold as a protection device for a trolling motor. I'm thinking it will be fine for my application or maybe there is something else used for this application. The one i'm looking at is manual reset with a lever that pops out and not a fuse type that has to be replaced.
Thanks for your input.
 

danemayer

Well-known member
2 thoughts:

1. If the wire is already getting warm, do you really want it to get warmer by upping the breaker?
2. If you're not putting a load on that breaker, other than to recharge the batteries, you may have a problem with your Power Converter if that's when the breaker trips.
 

kab449

Active Member
2 thoughts:

1. If the wire is already getting warm, do you really want it to get warmer by upping the breaker?
2. If you're not putting a load on that breaker, other than to recharge the batteries, you may have a problem with your Power Converter if that's when the breaker trips.

The wire got warm where it was attached to the 50 amp circuit breaker. Heartland installed the automotive type with the 1/8" studs. It was not warm away from the breaker. The Circuit Breaker was that hot I could not touch it.
The AGM Batteries are taking all the power the converter produces.
 

Flick

Well-known member
2 thoughts:

1. If the wire is already getting warm, do you really want it to get warmer by upping the breaker?
2. If you're not putting a load on that breaker, other than to recharge the batteries, you may have a problem with your Power Converter if that's when the breaker trips.

Something is causing the overcharge situation. Even though your batteries are new, check to be sure one is not bad. If the batteries check out good, as has been said, check your converter output. Sounds like the breaker is doing it’s job by tripping. Replacing that with a larger breaker at this point is probably not a good idea until you are sure that something is not causing it.
 

kab449

Active Member
Something is causing the overcharge situation. Even though your batteries are new, check to be sure one is not bad. If the batteries check out good, as has been said, check your converter output. Sounds like the breaker is doing it’s job by tripping. Replacing that with a larger breaker at this point is probably not a good idea until you are sure that something is not causing it.

The converter will output 80 amps. Im pretty sure the batteries are taking all 80 when discharged. The choke point is the 50 amp circuit breaker Heartland has placed on the line that goes to the battery from the disconnect. It gets really hot and keeps tripping and resetting. My concern was if the 6awg wire will handle the 80 amps of current going to the batteries. The 6 awg wire is only 10' long at the most.

- - - Updated - - -

Why are the batteries at 50%?
No hookups and running the residential refrigerator off the inverter.
 

wdk450

Well-known member
The converter will output 80 amps. Im pretty sure the batteries are taking all 80 when discharged. The choke point is the 50 amp circuit breaker Heartland has placed on the line that goes to the battery from the disconnect. It gets really hot and keeps tripping and resetting. My concern was if the 6awg wire will handle the 80 amps of current going to the batteries. The 6 awg wire is only 10' long at the most.

- - - Updated - - -


No hookups and running the residential refrigerator off the inverter.

You have discovered an engineering deficiency that I discovered years ago. I feel blessed that Heartland chose to use such a premium battery charger/converter as the progressive 9200 series. I am convinced it is the best for long battery life. Mine is only 60 amps, but that is still greater current than the NON-SELF RESETTING 50 amp breaker between the converter/charger and the battery. I would bet that momentary charging overcurrents at this breaker are responsible for the many reports we hear on this forum of the 50 amp breaker with the teeny, tiny, reset button tripping. I personally choose to depend on the additional current from the converter/charger when I set up on arrival, and when I depart and RV site. I always connect my shore power cord first thing upon arrival, and disconnect shore power last thing during departure. That way the 60 amps from my converter charger is helping lift the 5th wheel pin of off of my truck hitch, and putting out the slides.

As to your breaker heating up: It works on the principle of a bi-metalic strip heating up under current flow, and bending enough to break the current path. So some heating is normal. I would think about replacing the breaker with the same sized new one to maybe eliminate the heating felt, maybe due to poor breaker contacts. See this YouTube video of how a self-resetting 12 volt breaker works, for an idea of how your non-self resetting breaker looks inside:
https://www.youtube.com/watch?v=vA1cz021OvU

The charger to battery 50 amp breaker is probably non self-resetting due to fire safety regulations. The inside trailer and external lighting loads which can be used continuously or long term on the fusepanel that is connected to this circuit could cause heating and maybe a fire if the breaker kept resetting itself. The other high current breakers on the same bus bar feed intermittent use devices like the landing gear and slides which shouldn't heat the wires much over their short usage cycles, and are judged to be safe to use with self-resetting breakers.
 

kab449

Active Member
You have discovered an engineering deficiency that I discovered years ago. I feel blessed that Heartland chose to use such a premium battery charger/converter as the progressive 9200 series. I am convinced it is the best for long battery life. Mine is only 60 amps, but that is still greater current than the NON-SELF RESETTING 50 amp breaker between the converter/charger and the battery. I would bet that momentary charging overcurrents at this breaker are responsible for the many reports we hear on this forum of the 50 amp breaker with the teeny, tiny, reset button tripping. I personally choose to depend on the additional current from the converter/charger when I set up on arrival, and when I depart and RV site. I always connect my shore power cord first thing upon arrival, and disconnect shore power last thing during departure. That way the 60 amps from my converter charger is helping lift the 5th wheel pin of off of my truck hitch, and putting out the slides.

As to your breaker heating up: It works on the principle of a bi-metalic strip heating up under current flow, and bending enough to break the current path. So some heating is normal. I would think about replacing the breaker with the same sized new one to maybe eliminate the heating felt, maybe due to poor breaker contacts. See this YouTube video of how a self-resetting 12 volt breaker works, for an idea of how your non-self resetting breaker looks inside:
https://www.youtube.com/watch?v=vA1cz021OvU

The charger to battery 50 amp breaker is probably non self-resetting due to fire safety regulations. The inside trailer and external lighting loads which can be used continuously or long term on the fusepanel that is connected to this circuit could cause heating and maybe a fire if the breaker kept resetting itself. The other high current breakers on the same bus bar feed intermittent use devices like the landing gear and slides which shouldn't heat the wires much over their short usage cycles, and are judged to be safe to use with self-resetting breakers.

circuit breaker.jpgThis is what I am proposing to replace the mini automotive circuit breaker Heartland installed. I am going to replace the 50 amp heartland installed with the 80 amp version of this to be able to utilize the capacity of the converter. My concern is the wiring heartland installed from the converter to the automotive mini circuit breaker. I traced it and it is #6awg all the way from converter to buss bar to battery disconnect to the battery bank.
A check with the 12 wiring specs says 6 gauge is good for 100 amps at 12 volts up to 15 feet. I'm thinking I should be fine but will monitor it the first couple of times recharging. I'm going to rewire the battery charge feed to bypass the buss cluster mess.
The other concern I had was with the manufacturer of the circuit breaker. They recommended a lead of #4 wire for 80 amps. The actual use of this circuit breaker is for a trolling motor, so i'm thinking this application requires a greater safety margin due to dealing with motors which can draw a lot of current on start up. Battery charging should be the largest draw on the RV.
 

kab449

Active Member
UPDATE FOR ALL INTERESTED

Battery Charge Circuit_LI (2).jpg
https://www.amazon.com/Automotive-R...hes/b/ref=dp_bc_aui_C_5?ie=UTF8&node=15734151

I added a different 6 gauge wire charge line directly from the converter to the circuit breaker circled in the picture and then to the batteries. The circuit breaker is the one circled in blue in the above picture. I kept the rest of the wiring just as manufactured. I just added another 6 gauge line to carry the charging voltage directly to the batteries and not routed through the weak automotive circuit breakers.
I ran the batteries down to 12 volts and plugged the RV into shore power. The converter switch was on boost which gave 14.3 charging volts and all 80 amps.
The wires never got hot, just a little warm at the terminals and the 2 AGM batteries charged to 90%n about 2 hours. Success.
 

danemayer

Well-known member
UPDATE FOR ALL INTERESTED

View attachment 63889
https://www.amazon.com/Automotive-R...hes/b/ref=dp_bc_aui_C_5?ie=UTF8&node=15734151

I added a different 6 gauge wire charge line directly from the converter to the circuit breaker circled in the picture and then to the batteries. The circuit breaker is the one circled in blue in the above picture. I kept the rest of the wiring just as manufactured. I just added another 6 gauge line to carry the charging voltage directly to the batteries and not routed through the weak automotive circuit breakers.
I ran the batteries down to 12 volts and plugged the RV into shore power. The converter switch was on boost which gave 14.3 charging volts and all 80 amps.
The wires never got hot, just a little warm at the terminals and the 2 AGM batteries charged to 90%n about 2 hours. Success.

So, just to be clear, you now have a direct connection from Power Converter to Battery, with an 80 amp breaker in-between.

How do the breakers on the buss bar get powered now? Still powered from the original wires to the Power Converter and battery? Some other path?
 

kab449

Active Member
So, just to be clear, you now have a direct connection from Power Converter to Battery, with an 80 amp breaker in-between.

How do the breakers on the buss bar get powered now? Still powered from the original wires to the Power Converter and battery? Some other path?

I moved the wire from the converter on the mini breaker heartland installed on the buss bar. This is essentially is the feed to the buss bar when plugged in to shore power. I installed it to the input of the 80 amp breaker I installed. Then I made a 16" cable that installs on the same input post on the 80 amp breaker and ran to the mini breaker that I took the feed from the converter off. In essence the converter now feeds the new 80 amp breaker and the old mini breaker. Then on the output of the new 80 amp breaker I made another 16" cable that runs directly to the batteries. With the existing wiring in place the converter has 2 charge paths to the batteries now. The original path went through the mini breaker to the battery disconnect and then through another wire and mini breaker to the battery. The choke points were the mini breakers where the heat would build up and trip them stopping the charging of the batteries so when I woke up the batteries were not charged and I had to baby sit the mini breaker until the amperage tapered off.
The new path is more robust to carry the total output of the converter. Electricity will follow the path of least resistance.
I wish I was better at pictures. 1 picture is worth a 1000 words.
 
Top