Yes. Assuming it is essentially a toroidal CT with the power conductors run through its hole. There might be a small effect on sensitivity because the two conductors (of the three) in use are not symmetrical in the core hole.

Some local electrical codes will require an RCCB setting and operate time to be tested after installation, to prove its performance is within the necessary limits.

Thanks.

Sensitivity is not critical. As per the local code, it should work. They are not strict about the time.

Yes, as has been mentioned already, it should work. Slight asymmetry is a good point.

There is one other thing ... i refer to the "Test Trip" feature. In my house, the R-phase within the 3-phase RCD is used for this purpose. The electrician had used the B-phase to wire up in my house. So, the Test trip (a monthly test is mandated by the Indian Electricity Code)did not work. Solved when i reconnected the house wiring through R-phase.

Normally, 3 phase (I understand without neutral) RCCB are not intended to be be connected to single phase loads. On the three phase supply, the voltage between lines should be 400 V for example (in the case of a 230/400 V system), according to what is written on the RCCB. In the case you wish to supply the RCCB with 230 V between lines, there is a risk that the test function will not operate correctly, due to a too low voltage value.

I would not support in this case to use 3-Phase RCCB with single phase load, unless the single phase load is 400 V.

If you want additional information you may use the following wiki for electrical installation, using the following url.

http://www.electrical-installation.org/enwiki/Residual_current_differential_devices_(RCDs)_(_full_page_)#Types_of_RCDs

Regards,

Jean-François

In India at least, RCDs (and RCBOs, etc) are available in two- and four-pole versions only. So, the test trip is wired between one phase an the neutral invariably. No issue in such a case about using a 3-phase RCD on 1-Phase. Except as already covered.

A good point, JF-REY.

It would mean the OP has to use the two poles between which the test is wired for his single phase. If the OP is determined to use what he has, the test button may work at 230V.

On the bench one can measure the DC resistance D between the test poles [button pushed], then add a series test resistor R on the 230V side and energise input at 230V and press test.

So long as an R value can be made say 20% of D and the test trip button still works, then "Test not working, Boss" is not likely to become a nuisance.

thanks for the valuable views.

my system is 380V /230V (3ph/1ph).

3 phase RCCB means 4 pole RCCB . single phase RCCB is 2 pole RCCB.