Operating manualOxygen sensor module FCX-MLxx-CH & FCX-MLxx-Extern -CH Competitive sensor & power supply solutions worldwide

This manual contain information on how to operate the standard Pewatron OEM FCX-MLxx-CH and FCX-MLxx-Extern-CH products. The standard FCX-MLxx-CH configuration always have the oxygen sensor soldered onto the PCB and covered with an aluminium flow housing. The standard FCX-MLxx-Extern-CH configuration have the oxygen sensor connected to the PCB via a 30 cm long cable. The oxygen sensor can be chosen from a selection of 3 sensors; 3) the FCX-UWC 0.1.95% (xx = 95) As an example the FCX-ML95-CH Module is a 0.1-95% FCX-UWC oxygen sensor module used in flow applications or in applications where a gas...

1 List of Contents Page 1. Safety instructions

2 Customer Service At PEWATRON AG, we want to offer you the best customer service possible. If you have any questions or comments about your FCX-MLxx-CH or FCX-MLxx-Extern-CH modules, we would be happy to hear from you. Should you have any problems with the modules, please contact us for advice and support. We recommend that all service and repair work on the unit be done exclusively by our customer service or specially trained personnel. You can reach us at the following addresses: Headquarter: PEWATRON AG Thurgauerstrasse 66 8052 Zurich Switzerland Tel +41 (0)44-877 35 00 Fax +41 (0)44-877...

3 Safety instructions Danger sources that could result in personal injury or damage to machinery are explicitly indicated in the appropriate places in the user documentation. Before installing the machine, please read this operating manual carefully. Pay particular attention to the sections explaining possible hazards. Warnings and instructions are shown as follows: A Means that failure to follow the instruction indicated can lead to personal injury. Means that the instruction indicated must be followed exactly to prevent damage to the machine. Competitive sensor & power supply solutions worldwide...

4 Measuring Principle The sensor module is a complete solution for fast and accurate oxygen concentration measurements within the range 0...5% (ML05), 0...25% (ML25) or 0.1...95% (ML95). The sensor and the measurement electronics are located on a PCB (FCX-MLxx-CH). Alternatively, the oxygen sensor can be connected to the PCB via a cable (FCX-MLxx-extern-CH). The electronic amplifies the raw sensor signal and the output is a logarithmic current output signal 4.20mA (according to IEC 60381) as a function of oxygen partial pressure (see Appendix) Zirconium oxide, heated to about 450 °C, is penetrable...

5 Commissioning 5.1 Mechanical Installation The PCB has dimensions 75 x 40 x 28 mm (including the flow housing) (Fig.1.). There are two different variants for how the sensor can be connected to the module: Soldered directly onto the PCB or using a plug cable connector. In Fig. 2 below is shown the PCB with a sensor soldered directly onto the PCB and covered with an aluminium flow housing. In Fig.3 below is shown the PCB without a sensor, but with a plug cable connector. Fig. 1 PCB electronic layout for FCX-MLxx-CH/FCX-MLxx-Extern-CH Fig. 2 PCB side with flow housing; FCX-MCxx-CH Fig. 3 PCB side...

In each corner of the PCB, there are mounting holes with a diameter of 3.5 mm. The distance between the centre of mounting holes are 67 and 32 mm, respectively. A The PCB has highly sensitive circuitry. During installation, be careful that none of the caution components are damaged mechanically. 5.2 Pneumatic connections The flow housing has two hose connectors with a diameter of 5 mm. The direction of flow can be chosen arbitrarily. A Hoses containing silicone should not be used. Gases containing silicon destroy the sensor Caution cr GND Stromausgang (4..20 mA) GND Speisung (10..28 VDC) a The...

6 Environment Condition See also under 11. Specifications, in particular for the temperature and humidity ranges (not condensing). • Operation outdoors not permitted. • Protect from moisture The sensor temperature is about 450 °C. Please note in any case the resulting hazards for applications with reactive gas mixtures. Potentially explosive atmospheres The unit may under no circumstances be operated in or with potentially explosive atmospheres. 7 Warm Up Time The module need a warm up time of approx. 3 minutes. After 3 minutes the sensor delivers an output signal which is within the accuracy...

9.1 Calibration Adjustments It is recommended to check the device periodically by running it under regular lab conditions and flush the sensor with regular air (20.95% O2). 9.2 Adjustment Span and Zero Initial calibration of the ML module needed for operation has been carried out at the factory. The result of a measurement in air and at a temperature of 25°C should be 20.95 %O2 +0.2/-0.5% O2. Should there be a higher difference the module output can be adjusted according to the following procedure: 1 Attach the module to the supply 2 Use the sensor in regular air (20.95% O2). For the 0...5% sensor...

9.3 Adjustment if the sensor need to be replaced 1. Attach the module to the supply 2. After approx. 10 minutes adjust the sensor heating (U Heat) using the potentiometer (Heizspannung) and jumpers S1 and S2 for fine adjusting (see jumper configuration below). Please note that the VH differs from sensor to sensor and has to be adjusted at an accuracy of +0.005V. The corresponding values can be found on the attached calibration sheet. open open close open open dose close close 3. Use the sensor in regular air (20.9% O2). For the 0...5% sensor please use a N2-O2 gas with an oxygen concentration...

10 Important notes 10.1 Restrictions 1 Do not remove the sensor from the circuit board. 2 Do not change the length of the lead wires. 3 Please use regulated DC power source with current capacity over 1 ampere/pc. If current capacity is not sufficient, the sensor module will not operate correctly. 4 This sensor module was adjusted for O2-N2 system. Output characteristics may change if there are other gases present in the gas mixture to be measured. 5 Don't use in a gas that contains the halogen atoms (F, Cl, Br). The sensor can be damaged by decomposition of a gas containing halogen atoms. 6 SOx,...