Setup And Operation; Applying Power; Emission Current - Instrutech Hornet User Manual

Instruction Manual
5

Setup and Operation

5.1

Applying power

Connect power to the IGM401 using the designated pins 4 and 2 of either the 9-pin D-sub ANALOG or the
RS485 COM connector. Do not connect power to both connectors simultaneously.
CAUTION! The +24 Vdc Power and Power Ground pin-out connections are not the same on the ANALOG and
RS485 COM 9-pin D-subminiature connectors of the IGM401. Equipment damage may result if a mating
power/control cable is not wired for the correct power and ground connections. Be certain that you observe the
correct pin-out designation for the connector on the IGM401 that you intend to connect to.
Alternatively, you can power the device by connecting InstruTech's PS501-A power supply to the ANALOG
connector of the IGM401. When you connect power, the display will show "UNIT STATUS OFF". This indicates
the display is on but the filament is not turned on and the sensor has not been activated yet. Read this user
manual in its entirety before activating the sensor. Refer to
details.
5.2

Emission Current

Either 4 mA or 100 µA (0.1 mA) emission current are available settings for electron emission current.
1) In clean applications and operating at higher pressure ranges (5.00 x 10
100 µA emission current setting is preferred.
2) At lower operating pressures (1.00 x 10
should be used.
3) The emission current can also be set to automatically switch between 4 mA and 100 µA. This results in
optimal and stable pressure readings over the entire measurement range from low to high vacuum. For
example, if an application requires that pressure measurements be performed by the ion gauge from
pressures lower than 5.00 x 10
automatic emission current switching feature of this instrument. Switching of the emission current may
be programmed to take place at any pressure from 1.00 x 10
4) When using a diffusion pump or other pumps that use fluids, there is a possibility of the pump oil vapors
entering the IG transducer. These vapors may form an insulator on the internal components of the
transducer which can lead to instability or failure in controlling the emission. In this case, the 4 mA
emission current may provide improved operating lifetime and measurement performance.
InstruTech, Inc.
section 5.9
-9
Torr to 5.00 x 10
-6 -2
Torr to 5.00 x 10 Torr, the user may want to consider using the
titled "Activating the sensor" for further
-6
Torr to 5.00 x 10
-4
Torr) the 4 mA emission current setting
-6 -4
to 1.00 x 10 Torr.
IGM401 Hornet
-2
Torr) the
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