A circuit breaker IS essentially a contactor. A mechanically held contactor that is opened either mechanically, thermally or electrically.
The electrically held contactors we are using in e-stop circuits require power to the coil to close and hold the contacts that supply the main power to the control panel. The GFI shunt method requires the lack of a leakage current to ground to maintain main power at the control panel. To interrupt main power to the panel, both systems require a switch and the contactor device to function properly
They seem very similar but the fundamental difference is that the contactor is electrically held and the breaker is mechanically held. Removing power from the coil of a contactor and having it return to it's normal open state is just more reliable than the inner workings of a GFCI device. At least that's my mumblings on the topic...
The electrically held contactors we are using in e-stop circuits require power to the coil to close and hold the contacts that supply the main power to the control panel. The GFI shunt method requires the lack of a leakage current to ground to maintain main power at the control panel. To interrupt main power to the panel, both systems require a switch and the contactor device to function properly
They seem very similar but the fundamental difference is that the contactor is electrically held and the breaker is mechanically held. Removing power from the coil of a contactor and having it return to it's normal open state is just more reliable than the inner workings of a GFCI device. At least that's my mumblings on the topic...