Fast Gas Injection System

FAST GAS INJECTION SYSTEM

The General Atomics fast gas injection system is designed for injecting short (millisecond or longer) pulses of nonreactive gases into a vacuum system. The level of flow is measured with a small pressure sensor and the flow is feedback regulated so that the actual flow matches the demand.

Originally developed for fusion research devices, the piezoelectric valves and pressure sensors can be used in large magnetic fields. They are made of completely nonmagnetic materials and have been used in magnetic fields up to 2.4 T.

Gas Injector	Valve Controller
	The valve controllers, which contain the control and feedback circuitry, are mounted in a separate chassis which can be separated from the valves by up to 30 meters. Up to 4 valves can be controlled by individual plug in modules in one of the chassis. The flow can be manually set from the front panel of the controller or remotely programmed using an input voltage.

GAS INJECTOR FEATURES

piezoelectric gas injection valve
flow rate up to 500 torr-liter/s
opening time: 2 ms after application of voltage
flow measured by pressure sensor mounted on valve
valve and pressure sensor insensitive to DC magnetic fields
gas pressure up to 6.5 atm (absolute)
gas input: miniconflat flange
mounting: 2 3/4 inch conflat flange
alternate vacuum flanges available

VALVE CONTROLLER FEATURES

controls up to 4 gas injectors through individual plug-in modules
local manual control or external voltage programming for each control module
voltage control in range of 0-10 V
0-10 V analog output from pressure (flow) sensor on each valve
adjustable voltage waveform to match characteristics of various piezoelectric valves
up to 30 meter cable lengths to valves

FUSION RESEARCH USERS

Doublet IIA, Doublet III, DIII-D at GA
ISX-A, ISX-B at ORNL
TEXTOR at IPP Jülich
ASDEX-Upgrade , Wendelstein 7AS at Max-Planck-Institut-für-Plasmaphysik
ZT-40 at LANL

Prices
Contact: Dr. Keith Burrell, 858 455-2278