These Agilent Varian turbo pump vent valve kits have 0.5 mm orifice, are normally open (N.O.), and are closed when the turbo controller is powered on. In the event that power is lost this vent valve will open and start introducing air into the turbo at a rate that will bring it to a safe stop. This helps extend the life of the turbo by limiting the amount of time it spends while passing through resonant frequecies, which are hard on the pump's bearings (you can hear the pump actually get louder when it passes through these resonances). Venting after power loss is also important to prevent backstreaming from the backing pump, if vacuum is left on the turbo after power failure oils or debrises from the backing pump could be sucked back into the turbo pump. We recommend a vent valve and or a roughing line normally closed (N.C.) isolation valve to protect the turbo during power failure. This kit includes the hardware needed to mount to the side of a the Agilent Varian turbo pump. It is designed to plug into the Agilent Varian rack mount turbo pump controller, see J7 in center photograph, and have Agilent Varian Part Number 9699844. We also sell a vent valve extension cable 5 meters, Agilent Varian part number 9699941. Please see the available instruction manuals in our PDF download section Below.

They works with the following turbo pump models:

• TwisTorr 74 FS
• TwisTorr 84 FS
• TwisTorr 305 FS