Maintenance - Instrutech Hornet User Manual

Instruction Manual
The values of filament voltage and current presented below are approximate values that one may see in the
Research screen. The representative, average values used in this table may vary depending on the condition of
the filament and the vacuum chamber environment. For example, you may see a reading of 2.0 V at 100 μA
emission current with a corresponding filament drive current of 2.1 A. This doesn't mean that because the
voltage is higher than the value listed (1.7 V) above that there is a problem with the IG. The readings taken
should be viewed with the notion that there may be an indication of reaching end-of-useful filament lifetime if
the power required to sustain emission current continues to increase over time.
Indication
Filament voltage values are
present for several seconds
immediately after turning IG ON,
but then the values are zero
All parameters in the R&D screen
are zero after IG turn ON is
attempted
IGM401 filament voltage is
greater than 1.7 V and filament
current is greater than 2.5 A with
emission current = 100 μA
IGM401 filament voltage is
greater than 2.3 V and filament
current is greater than 2.7 A with
emission current = 4 mA
9.6

Maintenance

In general, maintenance is not required for your InstruTech module. Periodic performance checks may be done
by comparing the gauge to a known reference standard. When using the transducer in gases containing
contaminants or materials that react with the filaments of the hot cathode ion gauge, periodic degas and
switching to the alternate filament from time-to-time is recommended for longest useable transducer lifetime.
When the hot cathode (filament) of the ionization gauge transducer is at or near end-of-life, transducer (sensor)
replacement is recommended.
InstruTech, Inc.
Possible Cause
Filament is contaminated or
filament has reached end-of-useful
operating life for required emission
current setting
Failed electronics
Filament nearing end-of-useful-
operating-life
Filament nearing end-of-useful-
operating-life
Possible Solution
Switch emission current setting from initial
setting and re-start the IG; make several
attempts to establish emission current at both
100 μA and 4 mA.
Switch to second filament or replace ion gauge
sensor
Replace the IGM401 electronics
Switch to second filament or replace ion gauge
sensor
IGM401 may be operated at either 100 μA or 4
mA emission current setting. If trouble with
maintaining 4 mA emission current (Ie)
persists, switch to 100 μA emission current.
IGM401 Hornet
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