In Enphase installations, the IQ Relay (network system relay controller) acts as a physical disconnection device relay controller for single-phase installations. During specified grid abnormalities, the IQ Relay disconnects the Enphase Microinverters from the AC grid, and when the voltages return to normal and the grid frequency is in the acceptable range, the IQ Relay reconnects the system. The IQ Relay works in series with the Envoy-S tobreak both line and neutral, when needed, per grid requirements.