MBRAUN MB 120B-G, Руководство по эксплуатации

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General
The MB-OX-SE-1 has been designed to control the atmosphere of MBRAUN Systems for residual Oxygen
content. The measuring range 0 - 1000 ppm is linear in the range of 0 - 100 ppm and over 100 ppm is only used
to estimate the oxygen content of the inert gas.
The semiconductor sensor made of Zirconiumdioxide is specific for oxygen, but because of the high sensor
temperature and the catalytic activity of the platinum coating of the sensor
,
there are low cross-sensitivities for
hydrogen as well as possible reactions with aggressive gaseous substances that can reduce the operational
life of the sensor.
Caution!
Operating the sensor at oxygen levels of >1000 ppm (e.g. in air) does not irreversibly damage the
sensor element, but it should be avoided. If exposed to air, it will take several hours until the sensor
will measure low oxygen levels correctly in Inert Gas.
Construction
The MB-OX-SE1 consists of the sensor and the special electronics separated by a gas-tight NW40 clamp-
flange. The sensor is protected against physical damage by a protective cage. The sensor leads are connected
to the electronics by vacuum-tight feedthroughs. The electronics are contained in a
n
airtight box mounted directly
to the back of the NW40 flange.
The measuring electronics
are
operated by 24 VDC. It supplies a 0 to 10 VDC output proportional to the
oxygen concentration. An additional input switches the heating element of the sensor on and off to control the
temperature of the sensor. If this input is not used, an internal jumper has to be set to operate the probe.
Electronics and Sensor Element have been factory-calibrated with certified calibration gases; there are no user
- accessible adjustment points. (
Note
: On special request we may, on our decision, supply a calibration
procedure that allows trained technicians to recalibrate the sensor sensitivity in the low range up to 100 ppm)
Connector
5-pole socket ( LEMO ):
Signal 0 - +10V
Pin-Nr. Connection
Oxygen Analyzer (MB OX-SE-1)
!
2
3
4
5
Signal Ground
Supply Ground
24 VDC
Sensor Heating On (+ 24V)
Chapter 14
Analyzers
83
1