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mad avatar image

Multiplus 24/1600: Which diameter for battery connection?

Hi all,

I found different information in (german) datasheet and manual for the Multiplus 24/1600 about the diameter of the battery connection.

The datasheet says 35mm and the manual says only 25mm.

Which information is correct?

And if someone knows which diameter is necessary for a connection of about 2m it would be good to know as well.


Thanks in advance :)


Martin

battery connection
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2 Answers
seb71 avatar image
seb71 answered ·

That is not the diameter. It is the total surface area (in square mm) of the cross section (the copper wires only).


For your 1600W/24V inverter and 2m wire length, go with at least 35 mm2 wires between the inverter and the battery (or inverter - busbar and busbar-battery).

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alan avatar image
alan answered ·

General rule of thumb is the bigger the better on high current DC runs to reduce voltage and subsequent current droop. There is a point where there is little return however 1 size up doesn’t cost a great deal more and guarantees that there will be no problem. Another way to look at is it will also increase efficiency of the system as there will be less loss of power being converted to heat.

By the information here https://www.victronenergy.com.au/upload/documents/BatteryCables.pdf

And many other cable ratings from various manufacturers.

25mm sq is good for 75A to 5m

The data sheet more than likely shows the max cable size that fits in the screw terminals (assume you are talking about the new multiplus).

Id go for 35sq mm to allow for surge currents, or longer runs.

Remember all other sections of the DC “Bus” must match this gauge. Battery Links etc.

Check out the wiring unlimited book victron has released if you haven’t already.

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