Yeah, as you can see in the link I posted a few pages back, this is how it works:
1. Float valve in sump connected to drain pump.
2. When water level rises, it triggers the float valve which triggers the pump to drain the water.
3. Water feed line has a normally-closed solenoid, which only lets the water pass through if it has power.
4. If power goes out, solenoid closes and no water passes through, so no risk of flood.
5. The solenoid is also connected to a safety switch.
6. If the water goes past the float valve and touches the safety switch, it kills the power to the solenoid, which shuts off the flow of water.