Fujitsu inverter wiring

[Tbird650]

Hi, I have a Fujitsu inverter heat pump. The numbers are AOT12LFBC & AST12LSBCW.
It's a pre-owned unit and I'm currently fitting it to my house.
My query is with the wiring connections/terminals on the outside unit. These are marked N, L & 3. Also a screw for earth. There's a four core wire running to it.
My first thought is: N for neutral, L for live & 3 for signal? Can anyone confirm or correct me please.

kindest regards

[Tbird650]

Pic of the wires to be terminated. Red, blue, & white wires to be connected to the N, L & 3 terminals.

[nike123]

Correct!
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