Please refer the attached document connection in 3P RCCB.

You can follow the same document for connection in three-Phase without neutral.
>> If you are using Acti9 range RCCB, You don't need to add the resistor with iID Acti9 RCCB. You can directly connect the 3 phase on 3 poles of RCCB (without neutral).

>> If you are using the Multi9 ID range RCCB, we need to add a resistance with specific resistance values to be compliant with 380-415V. Please refer the attached sheet for connection & resistance values to e used with multi9 range of RCCB.
The devices have a toroid which gets energized on out of balance currents and trips .
The toroid does not care if there is 2 or 3 or 4 lines connected to it as far as out of balance current is concerned.
If there is 3 phases + N then all the phases and N conductors will vector sum to zero - unless there is out of balance current = trip if exceeding the threshold..
If there is 3 phases and No N conductor - then exactly the same applies = sum of the 3 currents = zero or you have a trip condition if the out of balance current is greater than the threshold.
We can get by without having a N conductor connected to the RCCB as below - because the test button creates a resistive load outside the toroid at rated voltage to test trip the device.

Released for: Schneider Electric Saudi Arabia