Renogy DC-DC MPPT and Victron Multiplus 12v 3000va

[thatsnailguy]

Hello,

I bought a Renogy DC-DC MPPT solar/alternator charger and Victron Multiplus 3000 inverter-charger. I want to know if I can hook both of these up at the same time to charge a bank of Battle Born LiFePO batteries.

Thanks in advance for the replies!

 

[Skelo]

I have the same question, but with Renogy's PCL2000 series Inverter/Charger.
I contacted them and they replied you cannot.
So it looks like I can't draw from the batteries for the Inverter and the same time charging from the vehicle though the DC to DC with MPPT charger.
I would have to some how switch in and out blocking diodes at 175 amps.
I did find this diode, but I worry about forward voltage drop.

 

[John Frum]

I have the same question, but with Renogy's PCL2000 series Inverter/Charger.
I contacted them and they replied you cannot.
So it looks like I can't draw from the batteries for the Inverter and the same time charging from the vehicle though the DC to DC with MPPT charger.
I would have to some how switch in and out blocking diodes at 175 amps.

I think there is some misunderstanding.

The ac inputs for both inverter/chargers can connect to the same ac domain.
And both the dc inputs and outputs for both inverter/chargers can connect to the same dc domain.
The only thing that must be separate is the ac outputs because they are un-synchronized.

 

[Skelo]

This was the response from Renogy...

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Thank you for contacting Renogy. We do apologize for the inconvenience this may have caused. We hope this email finds you well.

You can only connect your R-INVT-PCL1-20111S-US to your batteries and your RBC30D1S-US through solar or your batteries. You cannot connect the inverter to the MPPT Battery charger directly.

Should you have any other questions, please reply to this email or call us at 909-287-7100 Mondays through Fridays from 8:30 AM to 3:00 PM PDT. You can use the Case ID provided below as your reference.

Again, Thank you for reaching out to Renogy Support. Have a good day!
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So I'm thinking this might work. Schematic attached.

 

[John Frum]

This was the response from Renogy...

------------------------------------------------------------------------
Thank you for contacting Renogy. We do apologize for the inconvenience this may have caused. We hope this email finds you well.

You can only connect your R-INVT-PCL1-20111S-US to your batteries and your RBC30D1S-US through solar or your batteries. You cannot connect the inverter to the MPPT Battery charger directly.

Should you have any other questions, please reply to this email or call us at 909-287-7100 Mondays through Fridays from 8:30 AM to 3:00 PM PDT. You can use the Case ID provided below as your reference.

Again, Thank you for reaching out to Renogy Support. Have a good day!
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So I'm thinking this might work. Schematic attached.

Sorry my poor eyesight precludes me from understanding your drawing.

 

[John Frum]

What is the intended function of the diodes you propose?

 

[Skelo]

Is this better?

Switch/Relay modes:

1) Blocks current from Inverter charger when in DC to DC(MPPT) charging mode, but allow Inverter to provide AC.
2) Disconnects DC to DC charger when using Inverter charging function from shore power or batteries.

 

[John Frum]

Is this better?

No, sorry.

Switch/Relay modes:

1) Blocks current from Inverter charger when in DC to DC(MPPT) charging mode, but allow Inverter to provide AC.

This is not required.
Its totally normal to have more than one charge source connected to the system busbars.

2) Disconnects DC to DC charger when using Inverter charging function from shore power or batteries.

Not required.
As long as the combined charge current is within spec for the batteries everything is fine.

 

[John Frum]

Also the combo alternator + solar dc2dc charger has garnered a lousy reputation.
As did Renogy support.

 

[Skelo]

Then I've got to better understand why Renogy does not recommend it, since both units are their product.
I would assume since, as you said, phasing is not a problem with the DC side of things it should work.
They didn't even recommend a charge current setting as an option.

 

[John Frum]

Then I've got to better understand why Renogy does not recommend it, since both units are their product.

Probably because their support is clueless.

 

[Skelo]

If it's not clueless support what could Renogy possibly be doing inside those units that would preclude it from working and possibly damaging either unit.
Are MPPT outputs somehow sensitive to other DC charging sources?
My assumption was the Inverter/Charger in charging mode looks like another battery to the DC to DC(MPPT) charger.

 

[John Frum]

If it's not clueless support what could Renogy possibly be doing inside those units that would preclude it from working and possibly damaging either unit.

I could not begin to imagine.

Are MPPT outputs somehow sensitive to other DC charging sources?

No.

My assumption was the Inverter/Charger in charging mode looks like another battery to the DC to DC(MPPT) charger.

Not really.