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padmika avatar image
padmika asked

Diode Battery Combiner Voltage

I have installed a Diode battery combiner in a DC system.

But only later when i read the manual i realized it has a rated voltage of 12V or 24V.

But my system is 48V DC. But it works just fine.

My problem is...

the battery combiner is a set of Schottky diodes. How does a voltage has a part in this?

What will happen if i use it on a 48V system? (so far it seems to work without any problem)

Argo FET Diode
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3 Answers
Kevin Windrem avatar image
Kevin Windrem answered ·
If your AC-DC converter output voltage drops below the 27 volts current will flow opposite the intended direction. It is likely that the AC-DC converter voltage will be pulled up through the diode and any current will be small. Whether damage occurs depends on the part and how much current flows. This current will also put a small load on the battery.


I'd recommend the higher voltage diodes but this means you'll need to find a way to mount them and dissipate the heat produced, and to make connections to the diode's leads.

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padmika avatar image padmika commented ·
Thanks.

I do have a 60V one.

But honestly it's ugly and i was wondering if i could keep the Victron one. :-)

Guess i have to replace it.

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Kevin Windrem avatar image
Kevin Windrem answered ·

Exceeding the voltage rating could destroy the diode. But that would mean one input to the combiner would need to be greater than 24 volts than the other input.

Also note that with a diode combiner, any charging current from the output side of the combiner will not reach the battery.

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padmika avatar image
padmika answered ·

@kevin Thanks.

The way i have setup is DC from a AC-DC converter is kept at 56V and Battery output is regulated to 51V. Batteries have separate charger. So load is powered from AC-DC and if AC fails, will go from batteries and i once i get power, AC-DC doesn't charge batteries. That's why i installed the diode.

I did find another diode rated for 60V and 400A. but i prefer the victron... why i'm wondering.

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