Rapid Vacuum Isolation Valves offer extremely fast closing speeds to protect the vacuum system during a backpressure event caused by pump failure. Many valves do not close fast enough to prevent particles and turbulence from moving upstream and damaging the process.
In most applications, there are two isolation valves in the vacuum foreline; one near the chamber exit for process isolation and one directly upstream of the pump for preventative maintenance work.
The Rapid Isolation Valve can be triggered a number of ways, including:
Power to the pump - many pumps have accessory relays which can be easily tapped.
Programmable Automation Controller (PAC) or equivalent device providing logic.
Pressure Sensors, based either on a threshold pressure or a rate-of-rise.