Teledyne API Model 200AU NOX Analyzer Instruction Manual, 02293, Rev. F

9.2.4 Negative Output

1.Mis-calibration. The 'zero' gas that was used to zero the M200AU contained some NO gas - that is, it had more NO gas than that of the sample air. May also be caused by doing a zero calibration using ambient air. If NO/NOx OFFSET - TEST functions are greater than 150 mV, reaction cell contamination is indicated. Verify quality of zero air used it should have less than 1 ppt NO and correspondingly low equivalent values of interferent gasses .

2.Corruption of the Pre-reactor filter. If a significant signal was detected during the Pre-reactor cycle, that higher reading can enter the Pre-reactor filter. The value of the Pre-reactor filter is subtracted from the current reading, thus producing a negative reading. High Pre-reactor readings can be caused by:

A.Leaking Pre-reactor valve.

B.Electronic fault in the preamp causing it to have a voltage on the PMT output pin during the Pre-reactor cycle. Area around the high impedance section of the preamp contains conductive dirt.

C.Reaction cell contamination causing high background ( >40 mV) light readings.

D.Broken PMT temperature control circuit, or broken PMT cooler power supply - allowing high zero offset.

After fixing the cause of the high Pre-reactor filter readings, the M200AU will take 15 minutes for the filter to clear itself.

3. Check for leaks.

9.2.5 Excessive Noise

Common reasons for excessive noise are:

1.Leak in pneumatic system.

2.Light leak - check the sensor module with strong light.

3.HVPS noisy - see HVPS test procedure. See Section 9.3.8.5.

4.Defective electronic components on preamp board. - use optic test and electric test to check electronics, optics and observe noise.

5.Contamination of ozone generator and/or reaction cell - This can be wet air or impurities. This can be detected by high PMT readings with zero air as sample gas. Verify this condition by turning off the ozone generator using the DIAG mode command and observing a drop in PMT reading of more than 50 mV or 25 ppb. If the ozone generator or reaction cell is contaminated, disassemble and clean.

9-28

Page 163 Page 165
Page 164
Image 164
Teledyne 200AU instruction manual Negative Output, Excessive Noise
Page 163 Page 165

200AU specifications

The Teledyne 200AU is a cutting-edge analytical instrument designed primarily for trace and ultra-trace analysis of elements in various liquid samples. Renowned for its reliability and precision, this inductively coupled plasma mass spectrometer (ICP-MS) is widely utilized in environmental monitoring, food safety, clinical diagnostics, and geochemical research.

One of the distinguishing features of the Teledyne 200AU is its exceptional sensitivity, allowing for the detection of elements at concentrations as low as parts per trillion (ppt). This sensitivity is crucial for applications where even minute traces of contaminants can have significant implications. The instrument also boasts a wide dynamic range, accommodating high-concentration samples without compromising accuracy.

The Teledyne 200AU incorporates advanced technologies that enhance its analytical capabilities. At the core of its design is a robust ICP source, which ensures optimal ionization efficiency. The instrument also features a high-resolution quadrupole mass analyzer, which enables precise separation and identification of ions based on their mass-to-charge ratio. This feature is essential for distinguishing between isotopes and analyzing complex mixtures.

Another notable characteristic of the Teledyne 200AU is its user-friendly interface, which simplifies the operation and data management processes. The software is intuitive, offering sophisticated data processing algorithms that streamline analysis. Users can easily access real-time data visualization, facilitating timely decision-making based on analytical results.

The instrument is built with durability in mind, featuring a compact design that allows for easy integration into various laboratory environments. The Teledyne 200AU is also equipped with state-of-the-art safety features, including enhanced cooling systems and automated shutdown protocols to protect both the instrument and the user.

Moreover, the Teledyne 200AU supports a variety of sample introduction methods, including nebulization and laser ablation, providing flexibility to accommodate different types of samples and experimental needs. Its multi-element capability further enhances its versatility, allowing simultaneous detection of multiple elements in a single analysis.

In summary, the Teledyne 200AU stands out as a premier instrument in the field of mass spectrometry. Its combination of high sensitivity, advanced technology, user-friendly features, and robust design makes it an invaluable tool for scientists and researchers seeking precise elemental analysis across various disciplines.
Top Page Image Contents