VictronConnect / DC Home Accuracy Issues

[phoenixmoon]

What happened to the original converter that provided 12V from 120VAC input? Are you running an inverter? My preferred solution in this case is to leave the RV 12V system intact and power the AC-DC converter with the inverter. While this is inefficient, and it retains a bulky 12V, it simplifies things and provides a second layer of backup for your 12V items.

No idea / still there as far as I know.

I do run an inverter.

My off-grid setup terminates at a 50A RV power pedestal. Both of my 5th wheels plug in and run their 12V converters from AC. There have been times where my system is taken offline, but the trailers still have 12V power. One of the trailers has the DSL modem for internet powered directly by 12V, so it keeps my connection alive even if I lose AC power.



Does the charge controller display 24V?

Charge controller currently displays 26.5V, which I think is a yes.

The sense wire on the shunt is probably connected at the wrong location. It should be connected on the primary (+) terminal.

View attachment 153798
The sense wire 1
appears to be connected to location 2
should be connected to location 3

Note that you need to change the "Battery SoC on reset" from "Set to 100%" to "Keep SoC" as disconnecting this wire will cut power to the shunt and reset according to this setting.

Again, please, can you measure and report all 4 12V batteries with a voltmeter?

I've bolded questions in case they get overlooked in my blabberings.

I don't have a voltmeter, but I can probably have a friend come by tonight with one.

 

[sunshine_eggo]

No idea / still there as far as I know.

This might be concerning. Are you on shore power? It would not be good if your converter is powered by 120VAC, supplying 12V and only charging 12V of your 24V battery.

I do run an inverter.

Is it also a charger? make and model?

Charge controller currently displays 26.5V, which I think is a yes.

Yep!

I don't have a voltmeter, but I can probably have a friend come by tonight with one.

You absolutely, positively need a multimeter. Even a cheap harbor freight one. I would also encourage you to get a decent one with both DC clamp ammeter and AC INRUSH functions to be a total boss. Being able to measure DC current is a very useful when troubleshooting. INRUSH is only needed if you're trying to measure the surge of electric motors.

Will recommends a few on this page:

Tools

Do not buy cheap tools. You will thank yourself for years, and building a system will be MUCH EASIER. ( I make a commission for purchases made through the links below)

www.mobile-solarpower.com

All three lack the INRUSH function, but the Budget one would suffice.

 

[phoenixmoon]

This might be concerning. Are you on shore power? It would not be good if your converter is powered by 120VAC, supplying 12V and only charging 12V of your 24V battery.

I am not on shore power.

Is it also a charger? make and model?

My inverter is a Vevor 3500W pure sine wave inverter. I don't believe it's also a charger. I think my charger is an Iota. It has something called a "2-stage smart controller for use with DLS" connected to it.

You absolutely, positively need a multimeter. Even a cheap harbor freight one. I would also encourage you to get a decent one with both DC clamp ammeter and AC INRUSH functions to be a total boss. Being able to measure DC current is a very useful when troubleshooting. INRUSH is only needed if you're trying to measure the surge of electric motors.

I'll grab one.

So a couple weird things that are possibly relevant:

1) When I came home with the inverter off I was discharging in high sun. This is unusual / since the upgrade.
2) My charge controller reads 100 percent SOC / boost, VC reads 82 percent SOC.
3) I have two breakers for the 12V system. This morning when it wasn't charging much, I flipped one off and it started charging more. Charge came way up. Got home, saw it wasn't charging, flipped it back on, it started charging up.

 

[sunshine_eggo]

I am not on shore power.

Gotcha.

My inverter is a Vevor 3500W pure sine wave inverter. I don't believe it's also a charger.

Correct. It is not.

I think my charger is an Iota. It has something called a "2-stage smart controller for use with DLS" connected to it.

Iota is a common brand of converter. Is it this?

This is good for charging 12V LFP.

I'll grab one.

Yes please.

So a couple weird things that are possibly relevant:

1) When I came home with the inverter off I was discharging in high sun. This is unusual / since the upgrade.
2) My charge controller reads 100 percent SOC / boost, VC reads 82 percent SOC.
3) I have two breakers for the 12V system. This morning when it wasn't charging much, I flipped one off and it started charging more. Charge came way up. Got home, saw it wasn't charging, flipped it back on, it started charging up.

With your pulling 12V off part of the 24V, a shit show is brewing. At some point the 12V you are NOT pulling 12V from will be full when the 12V providing loads is empty. Even before this extreme condition, the full batteries will prevent charging because they would go overvoltage.

I would really recommend you parallel all the batteries back into 12V and charge them as 12V until you get to 14.4V.

 

[phoenixmoon]

Iota is a common brand of converter. Is it this?

This is good for charging 12V LFP.

It's connected to this.

DLS 27V 15A Converter and Charger - 15 Amp AC\DC Power Converter and Battery Charger for DC load operation and 24V battery charging

The DLS 27V 15A Power Converter/Battery Charger from IOTA converts nominal 108-132 AC voltage to 27.2 DC voltage for both DC load operation and 24V battery charging. As a power supply , the unit's

www.acuitybrands.com

With your pulling 12V off part of the 24V, a shit show is brewing. At some point the 12V you are NOT pulling 12V from will be full when the 12V providing loads is empty. Even before this extreme condition, the full batteries will prevent charging because they would go overvoltage.

I would really recommend you parallel all the batteries back into 12V and charge them as 12V until you get to 14.4V.

How do I do that? Also my inverter is 24V and won't work anymore if I do this, correct?

Also, how do I convert back to 24V properly? Should I just hire someone to do this?

 

[sunshine_eggo]

It's connected to this.

DLS 27V 15A Converter and Charger - 15 Amp AC\DC Power Converter and Battery Charger for DC load operation and 24V battery charging

The DLS 27V 15A Power Converter/Battery Charger from IOTA converts nominal 108-132 AC voltage to 27.2 DC voltage for both DC load operation and 24V battery charging. As a power supply , the unit's

www.acuitybrands.com

Ah, so you have a 24V converter. I assume this is a new addition since going to 24V?

How do I do that?

completely disconnect the batteries from each other, connect all (-) to each other and all (+) to each other. Connect MPPT to main terminals like this:


ignore the thinner wires.

Also my inverter is 24V and won't work anymore if I do this, correct?

Correct. That's going to happen eventually as you continue to draw from the 12V, and the 24V system will no longer be able to take a charge or power the inverter.

Also, how do I convert back to 24V properly? Should I just hire someone to do this?

Wire according to the previous sketches. This is pretty straightforward, so I think with a little planning, it can be DIY.