Installation; External Transfer Switch; Ground Relay; Current Transformers - Victron energy MultiPlus-II Manual

Installation

External transfer switch

Use a Schneider LC1G3304 TeSys Giga, 4-pole (4NO), AC-1 <=440V 440A contactor
Connect the coil directly to the NO and COM terminals of the MultiPlus-II "AUX
RELAY" of the L1 phase master unit.
Do not use a different contactor, as closing and opening times differ per brand and model.

Ground relay

The ground relay drive signal is supplied by the MultiPlus-II "Ext GND Relay"
terminals of the L1 phase master unit.
The "Ext GND Relay" output signal is limited to 24V / 200mA, so an extra relay with
a 24V coil that switches the actual ground relay must be installed.
The ground relay rating must match the total inverter power of the system.

Current transformers

Connect the current transformers for L1, L2, and L3 to the "Current Sense" inputs on the
respective phase master MultiPlus-II units.
Remove the wire bridge between the INT and COM terminals. Connect the red sensor
wire to the EXT terminal and the white sensor wire to the COM terminal. Ensure the
wire direction through the current sensor follows the arrow pointing towards the
Multi.
To prevent signal interference, avoid routing current sensor wiring parallel and close
to AC power wiring. This applies to all signal wires, including the VE.Bus cables.
Note that the higher rating of 400A sensors reduces current sense resolution, especially at low
currents.