Correct wiring of GFCI breaker
Here is how you can test without a meter.
Install the breaker. Connect the panel neutral pigta.l to the neutral bus bar.
Connect the hot from any circuit to one screw. Turn on the breaker (and something on that branch circuit).
Turn off the breaker. Now switch the circuit hot to the other screw. Turn on the breaker again.
For one screw (the hot) the breaker will do an immediate GFCI trip. For the other screw (the load neutral) the branch circuit will be dead.
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