Here is my wiring diagram. Could I please have some advise in what size cables I need for my system and what size DC Fuse Disconnector and what size HRC Fuses do I need?
Any help is much appreciated
asked
Is the Pylontech Cables too small to connect to my Multplus II?
How far are the batteries from the invterter in terms of battery length?
The manual for the inverter will tell you what cable sizes for the install and the fuse size.
You do need the pylontec cable for the battery terminal at least to the lynx (they are smaller than others as they are rated differently because they have different insulation). Size for your inverter again after that.
When looking at the Pylontech manual for US3000, they are specified for a peak charge/discharge current of 100 A for 15 seconds. In your drawing, there are two Pylontech batteries in parallel, therefore the fuse should be 200 A.
Guy Stewart has shown that the Pylontech cables are good for 178 A, cf. https://community.victronenergy.com/questions/41642/pylontech-battery-cable-spec.html
The maximum charge/discharge current for Pylontech US3000 is 74 A per battery module, i.e. 148 A for the two battery modules. Therefore the Pylontech cables are ok for two battery modules. I think it does not matter when the peak current exceeds for a few seconds the nominal current for which the cables are dimensioned.
In the drawing, there is a box shown between Pylontech batteries and Lynx distributor, probably for battery disconnection. With this box, the Pylontech cables would also end at that box and you would need additional cables to connect the box with the Lynx distributor. I think it would be better to connect the Pylontech cables directly with a 200 A Mega fuse in the Lynx distributor.
I believe that separate switch for disconnecting the batteries is not needed because the Pylontech batteries themselves can be switched off.
