Battery charging - different brand charge controller and inverter

[Shiba_Alex]

Hey Guys:

I was meaning to post this is a few weeks ago. I had recently installed a solar system on my rig with a Victron charge controller and Go-Power IC-3000 inverter. In both of the setups, I matched the charge settings, but I was wondering if I could have both the charge controller and inverter charging the batteries at the same time. Until I know the answer to this, I am turning off the charging function on the inverter and using the solar if there is a lot of sun and vice versa if I am hooked up to shore power. I am wondering because in my head, I see the charge controller trying to do a bulk charge while the inverter is doing a float charge and the batteries may not like that.

Let me know if I am being too cautious or if this is a common occurrence and I am worrying about nothing.

Alex

[jcussen]

Originally Posted by Shiba_Alex

Hey Guys:

I was meaning to post this is a few weeks ago. I had recently installed a solar system on my rig with a Victron charge controller and Go-Power IC-3000 inverter. In both of the setups, I matched the charge settings, but I was wondering if I could have both the charge controller and inverter charging the batteries at the same time. Until I know the answer to this, I am turning off the charging function on the inverter and using the solar if there is a lot of sun and vice versa if I am hooked up to shore power. I am wondering because in my head, I see the charge controller trying to do a bulk charge while the inverter is doing a float charge and the batteries may not like that.

Let me know if I am being too cautious or if this is a common occurrence and I am worrying about nothing.

Alex

Most people run both at the same time. Inverter/charger and solar controller will only read battery condition. They may have different voltage setpoints and absorb times, but don't believe you will have any problems. If you have a remote [bluetooth or wired] on your victron you can set your charge settings.

[Shiba_Alex]

I've got the SmartSolar controller for the Victron, so I was able to set it by bluetooth. And I have the remote for the Inverter/charger so was able to set that as well. If I can use both the charge controller and the inverter/charger at the same time to charge the batteries, that brings me to my next question.

Let's just say that the conditions are ideal and I have full power coming from the solar panels and I am hooked up to 50 amp shore power. With my solar setup, I can push a full 12v 50 amps from the controller to the batteries, and the inverter/charger can push 12v 125 amps to the batteries. So that means a total charging capacity of 175 amps. Wouldn't that fry the batteries? I have AGM batteries, so they should take a higher charge rate than normal flooded batteries.

I just want to make sure that I am doing things right and protecting my investment by not doing something that I shouldn't.

Alex

[cruizerEd]

I don't have the same system. I have a 3 40amp Blue Sky charge controllers and a Magnum MH2800 inverter. I have the advanced remotes for both systems so I can twiddle all of the settings. My batteries are 3 200AH LifeBlue LiFePO4.
The batteries will accept up to 80A each for a total of 240A, with a recommended rate of 60A each or 180 A max.
The solar produces 120A max but I rarely see that but 90 or 100A is not unusual.
The inverter will charge at 120A max.
I seldom charge with the solar and the inverter.
Normally I am charging with the inverter when there isn't much solar so typically the solar will only be contributing 20 or 30A.
I have run the system once or twice at about 200A of charging because I have started the gen only to have the sun come out.
Before doing any of this I loaded tested the system at 250A for at least 15 minutes after installation to make sure no heat was building up anywhere in the system.

It doesn't mater what batteries you have as long as you don't exceed the maximum (or ideal for best battery life) charging amps and that you do not exceed the capacity of you wiring.

Both charges will see the similar voltage from the batteries and will control the current appropriately. Do to slight differences in resistance and circuity one will probably roll off the current sooner than the other but this won't hurt anything.

Assuming lead acid and a low SOC (State Of Charge) say 50% both systems will start in bulk and supply the max current you have configured (or is available). One of the system will probably switch into accept mode sooner but the other will follow suit. Depending upon how your accept transitions to float the systems will also see float differently but not in a harmful way.

In practice it really only makes sense to use both systems off grid thus charging with the generator. In this scenario float and possibly even accept is not relevant since you will probably shut off the generator, and thus the inveter charger once the batteries have a enough charge.

In my particular case my inverter will not end acceptance based upon voltage and current. so I always monitor it and shut it off once the batteries hit about 99% SOC according to the BMS( Battery Monitoring System) built into the batteries. This is because LiFePO4 SOC can not be judged by voltage alone. I do this to avoid any chance of over charging the batteries with the inverter.

[jcussen]

Originally Posted by Shiba_Alex

I've got the SmartSolar controller for the Victron, so I was able to set it by bluetooth. And I have the remote for the Inverter/charger so was able to set that as well. If I can use both the charge controller and the inverter/charger at the same time to charge the batteries, that brings me to my next question.

Let's just say that the conditions are ideal and I have full power coming from the solar panels and I am hooked up to 50 amp shore power. With my solar setup, I can push a full 12v 50 amps from the controller to the batteries, and the inverter/charger can push 12v 125 amps to the batteries. So that means a total charging capacity of 175 amps. Wouldn't that fry the batteries? I have AGM batteries, so they should take a higher charge rate than normal flooded batteries.

I just want to make sure that I am doing things right and protecting my investment by not doing something that I shouldn't.

Alex

Never seen it happen. I have the Victron Multiplus and also Victron 150/70 with bluetooth. Set float .1 and absorb .1 volts lower on charge controller. No matter what the solar controller is doing, it will drop charge when I turn on the Multiplus charger. I have 4 8d agms, and even when 40% discharge, batteries will take about 110 amps for a minute or so, then drop down to 80 for bulk and lower for absorb.

[twinboat]

Batteries charge by voltage ONLY.

When the voltage reaches a set point every smart charging device will start to cut back the amp output, while maintaining the voltage.

Bulk mode = constant current
Absorb and Float mode = constant voltage.

The only way you will get too much charging is if your batteries are completely depleted. Even then, the voltage will climb quickly and the charger and controller will cut back.

[CountryFit]

You can charge your batteries with both shore and solar concurrently. I do it all the time, never a problem.