HACH LANGE ORBISPHERE 3650, Руководство пользователя

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Section 2 Specifications
2.1 General technical data
2.2 Instrument display options
2.3 Theory of operation
The sensor circuitry performs four functions:
•
Applying a constant voltage to the anode
•
Measuring the current flowing through the sensor
•
Compensating this current for sample temperature variations
•
Converting these resulting signals into a scaled current or voltage
The anode is held positive with respect to the cathode. Current flowing through the sensor due
to oxygen reduction at the cathode is converted to a voltage by an amplifier, the proportionality
between voltage and current being determined by the feedback resistance of this amplifier.
The output voltage is essentially a function of oxygen activity (partial pressure), temperature and
membrane permeability. Corrections for variations in membrane permeability are made when
the sensor is calibrated. The temperature compensation circuit accounts for temperature
variations. Hence the output voltage varies only with oxygen concentration.
Power Supply
Batteries: two C-type cells, NiCd or alkaline, each 26 x
50mm, 2.4 - 3volts total
Power Autonomy 40 hours continuous use
Signal Drift <0.5% of reading between service
Serial Output (RS232) Baud rate: 9600; Stop Bits: 1; Start Bits: 0; Parity: None;
Temperature Compensation Range -5 to 60°C
Instrument Operating Limits -5 to 100°C
Dimensions (HxWxD) 150mm x 115mm x 220mm
Weight 2.4kg
Enclosure Protection IP 65/NEMA 4
EMC Requirements EN 61326:1997 + A1:1998 + A2:2001 + A3:2003
ISO Certification ISO9001/EN29001
Instrument Model Display Units
Maximum Display
Resolution
3650/111
ppm/ppb (liquid)
ppm (liquid) only 1 ppb
0.001 ppm
3650/112 %/ppm (gaseous) 1 ppm
3650/113
ppm (liquid)
% (gaseous) 0.001 ppm
0.001%