FRG-700 Inverted Magnetron Pirani Gauge
17
6 Maintenance
Gauge failures due to contamination, as well as expendable parts
(filament), are not covered by the warranty.
DANGER
DANGER: contaminated parts
Contaminated parts can be detrimental to health and environment.
Before beginning to work, find out whether any parts are contami-
nated. Adhere to the relevant regulations and take the necessary
precautions when handling contaminated parts.
Caution
Caution: vacuum component
Dirt and damages impair the function of the vacuum component.
When handling vacuum components, take appropriate measures to
ensure cleanliness and prevent damages.
Caution
Caution: dirt sensitive area
Touching the product or parts thereof with bare hands increases the
desorption rate.
Always wear clean, lint-free gloves and use clean tools when working
in this area.
The gauge is factory-calibrated. If used under different climatic conditions, through
extreme temperatures, aging or contamination, and after exchanging the sensor,
the characteristic curve can be offset and readjustment may become necessary
The cold cathode measuring circuit, which is dominant for low pressures
(<1×10
-3
mbar), is factory-calibrated and cannot be adjusted. By way of contrast,
the Pirani measuring circuit can be adjusted. Any adjustment has a negligible effect
on the pressure range between approx. 10
-2
mbar and 10
2
mbar.
•
Screw driver 1.5 mm
•
Cylindrical pin ø
≈
3 mm
n
If you are using a seal with centering ring and filter, check that they are
clean or replace them if necessary (
→
16).
o
Put the gauge into operation (if possible, in the position, in which it will be
used later on).
p
Evacuate the vacuum system to p << 10
-4
mbar, and then wait 10 minutes.
q
Turn the nameplate counter-clockwise until the mechanical stop is reached.
6.1 Adjusting the Gauge
Tools required
Procedure
