V100 (2019-11)
Doc. Ref. XGC-320-100119
17
2.4
Overpressure and use with hazardous gases
WARNING!
Install suitable protective devices that will
limit the level of pressure inside your vacuum chamber to less
than what the vacuum chamber system components are capable
of withstanding. Ideal Vacuum Products gauges should not be
used at pressures exceeding 1000 Torr absolute pressure.
In cases where an equipment failure could cause a hazardous
condition, always implement fail-safe system operation. For ex-
ample, use a pressure relief device in an automatic backfill op-
eration where a malfunction could result in high internal pres-
sures if the pressure relief device was not installed on the
chamber.
The XGS-321 vacuum gauge tube connected to the XGC-320
controller is not intended for use at pressures above 20 psia
(1000 Torr); DO NOT exceed 35 psig (<2½ bars) pressure inside
the sensor. If your chamber goes to higher pressures, you
should install an isolation valve or pressure relief device to pro-
tect the gauge tube from overpressure conditions. With some fit-
tings, actual safe overpressure conditions may be lower; for ex-
ample, a quick-connect, O-ring compression fitting may forcibly
release the gauge tube from the vacuum chamber fitting with
only a few psi over local uncorrected barometric (atmospheric)
pressure.
CAUTION!
If the internal pressure of a vacuum gauge
device is allowed to increase above local uncorrected baro-
metric pressure (atmospheric pressure side), vacuum fit-
tings may release and possible overpressure conditions
may cause leaks that would allow the gas inside the gauge
tube to release into the atmosphere of the surrounding en-
vironment. Toxic, pyrophoric and flammable gases are ex-
amples of hazardous gases that if allowed to leak out of the
vacuum/pressure containment vessel into the atmospheric
environment, could cause bodily injury and possible dam-
age to equipment. Never expose the gauge tube internal
volume to pressure above local atmospheric pressure when
using hazardous gases.