Compur Statox 4120
pic. 2: Statox 4120 sensor head for Cl2 und ClO2
Operation principle
Ambient air enters the sensor (2) by diffusion through an opening at the bottom. The sensor creates a current - signal proportional to the gas concentration. This signal is amplified, temperature compensated and linearised. As a digital signal it is transmitted to the control module.
To protect the sensor from being poisoned by a high gas concentration, the Statox features a built – in air purge. This is activated when the gas concentration exceeds 95 % of the measuring range and stops when it has dropped below 80 %.
The battery pack (7) buffers the energy demand of the built – in pump (5). It is on permanent trickle charge. The pump is activated in the protection mode and during the self test to purge the sensor and provide test gas from the gas generator (4) to the sensor.
2.2 Statox 4120 rack
The Statox 4120 rack and the Statox 4120 control module provide the power supply for the sensor head. They are certified explosion proof [EEx ib] IIC. The rack must not be installed in certified
areas!
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