Analytical Industries GPR-1200 MS ATEX Portable PPB Oxygen Analyzer User Manual
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The sample system may include optional additional components such as a 3-way sample/span valve, a pressure
regulator, coiled metal tubing (samples must be cooled to at least 35-40º C for continuous use), coalescing filters,
scrubbers, 3-way sample/return valve, backpressure regulator, etc.
Note: The standard sample system is designed for positive pressure applications as described below under the
Installation section. From the factory the sensor is isolated inside the analyzer, sample system in the BYPASS
position, and the FLOW control valve set between 1 SCFH.
Caution: To avoid damaging the sensor comply with the following guidelines - failure to do so will
possibly damage the sensor and/or voiding the sensor warranty.
1. Drawing a vacuum on the sensor by pressurizing the analyzer: Results when sample gas flows into the analyzer,
builds up within the analyzer sample system because the outlet vent is restricted, and, is suddenly released when
the blockage is removed. This sudden release of backpressure draws a vacuum on the sensor stressing the sensor’s
front and rear seals to the point they rupture and the sensor leaks (voiding the sensor warranty).
2. Drawing a vacuum on the sensor when using a sampling pump downstream of the analyzer: Assure the FLOW
valve is completely open. If the FLOW valve is not completely open, the resulting vacuum drawn on the analyzer
may exceed the recommended limit and damage the sensor by stressing the sensor’s front and rear seals to the
point they rupture and the sensor leaks (voiding the sensor warranty).
3. Subjecting the analyzer to high positive pressure can damage to the pumps or other flow system components.
4. Introducing calibration span gas from a pressurized cylinder without pressure regulation: Adversely affects the
accuracy of the calibration. Follow above recommendations.
5. NEVER block the outlet vent of the sample gas on the side of the analyzer: This includes pressing your finger
over the outlet vent to confirm the flow indicator is operating.