The ZIROX vacuum probe is used to determine oxygen partial pressures in low-pressure equipment. Typical applications include vacuum processes (PVD, magnetron sputtering, and other plasma processes), surface treatment applications, and material-scientific investigations.

Note:

In contrast to the ZIROX normal pressure probes, the vacuum probe is not calibration-free. The reasons are the special sensor heater (inside the probe tube) and several conditions at the measuring electrode (energy removal depends on gas pressure and thermal conductivity). Therefore, isothermal electrodes, required for the correct use of the NERNST equation, cannot be realized. For process control, however, the use of empirically determined values is sufficient in most cases. For the measurement of oxygen partial pressures, the user must calibrate the probe (test measurements).

Inbuilt length	140...300 mm
Diameter	6 mm, with protection tube 16 mm
Mass	1.5 kg
Dimension clamp head	150 x 63 x 35 mm
Protection degree	IP54
Flange	KF40, others on request
Max. temperature at flange	60 °C
Power supply	24 V DC +/- 10 %
Current consumption	1.2 A
Heating power	30 W
Pressure range	1.5 x 10^5...1 x 10^-5 Pa
Sensor voltage range	0...400 mV or 0...1200 mV (range changing on circuit board)
Range (oxygen partial pressure)	1 x 10^5...1 x 10^-21 Pa
Output signal	0-20 mA
Accuracy	< 5 % rel. error
Sensor working temperature	700 °C (electronically controlled)
Offset (with protection sleeve)	-15...-20 mV
Helium leak rate	< 10^-8 mbar l/s
Gas flow	max. 10 m/s
Reference gas	Surrounding air
Reference gas flow	5...10 l/h (by internal pump)

1	+ 24 V
2	GND
3	+ Iout	20 mA corresponds to 400 or 1200 mV (as adjusted)
4	- Iout
5	Ready contact (potential free)	60V/1A DC or 125V/1A AC
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