Teledyne 200AU instruction manual Ozone FL

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

Table 9-1: Test Functions (Continued)

Test Function	Factory Set-Up	Comment
OZONE FL	80 cc/min ± 10	This is the Ozone flow. It is measured by a solid state flow meter,
		and thus is a true indication of flow.
		If you suspect there is no ozone being generated, disconnect the
		tube at the reaction cell and rub the end of the tube on your
		fingertips, then sniff your fingers. The odor of ozone should be
		readily apparent.
PMT	0-5000 mV	This is the instantaneous output of the PMT. During normal
		operation the value varies widely as the M200AU switches from
		NO to NOx to Pre-reactor modes. Changes in reading will be
		synchronized with valve switching. The PMT voltage values will
		be relatively constant when:
		1.	Electric test - variation in the 2000 mV signal observed will be
			sampling errors of the V/F board and preamp noise. See Section
			9.1.3.2.
		2.	Optic test - variation in the 2000 mV signal will be PMT dark
			current, preamp, HVPS plus item 1 above. See Section 9.1.3.3.
		3.	Sampling zero gas - signal from 1, 2 plus signal from ozone
			generator air
		4.	Sampling pure NO span gas - signal will be 1, 2, 3, above plus
			signal from chemiluminescent reaction. Slight pulsations will
			be noticed as the M200AU switches from NO to NOx. This is
			due to differences in flowrates in each channel. These
			differences are taken out in the calibration process resulting in
			slightly different slopes for the NO and NOx channels. Large
			pulsations when switching to the NOx channel is indicative of a
			bad moly converter.
		When sampling zero gas the PMT reading should be less than 150
		mV and relatively constant.
		High or noisy readings could be due to:
		1.	Excessive background light which is caused by a possible
			contaminated reaction cell.
		2.	Humidity (undried ambient air) in the ozone generator feed air.
		3.	PMT recently exposed to room light. It takes 24-48 hours for
			the PMT to adapt to dim light.
		4.	Light leak in reaction cell.
		5.	Improper slopes
NORM PMT	0-5000 mV	The Normalized PMT reading is to be used as the PMT reading
		during the FACTORY CALIBRATION procedure. In addition to
		the raw mV reading from the PMT this reading is adjusted using
		certain other factors to produce an accurate reading for the Factory
		Calibration procedure.
(table continued)

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