Abb CL3020 User Manual

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ABB MEASUREMENT & ANALYTICS | OPERATING INSTRUCTION

CL3020

CLD NOx analyzer

Measurement made easy

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Table of Contents
	Important precautions..............................................................................................	5
	Use dry, oil-free instrument air only.................................................................	5
	Safety notice.........................................................................................................	5
	Model CL3020 specifications...................................................................................	6
	Performance specifications...............................................................................	6
	Features ................................................................................................................	6
	Mechanical specifications..................................................................................	7
	Overview......................................................................................................................	8
	Measurement configurations............................................................................	8
	Theory of operation...................................................................................................	9
	Chemiluminescence measurement of NOx......................................................	9
	Zirconium oxide measurement of O2 ...............................................................	9
	Pneumatic design..............................................................................................	10
	Analyzer setup and quick start procedure...........................................................	13
	Connect the analyzer.........................................................................................	13
	Apply power to the analyzer and check diagnostics ...................................	14
	Set analog outputs of the analyzer ................................................................	15
	Calibrate the analyzer .......................................................................................	16
	Display screens and details of operation ............................................................	17
	Home screen, warnings, and alarms ..............................................................	17
	Calibration menu ...............................................................................................	18
	Diagnostic screen..............................................................................................	19
	Trend screen.......................................................................................................	20
	Config screen .....................................................................................................	20
	Analog output scaling screen..........................................................................	21
	Analog output trim screen ...............................................................................	22
	IP address screen...............................................................................................	23
	QR code ...............................................................................................................	23
	About screen ......................................................................................................	24
	Alarm screen.......................................................................................................	24
	Config alarms screen ........................................................................................	25
	Troubleshooting ......................................................................................................	26
	Diagnostics and operating parameters ........................................................	26
	Warnings and alarms ..................................................................................	26
	Sample and ozone flow ..............................................................................	26
	Converter temperature ..............................................................................	27

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Gas concentration readings ......................................................................	27
System checks....................................................................................................	27
Electrical connections and fuse ................................................................	27
Leak checking...............................................................................................	28
Component information ..................................................................................	28
Oxygen sensor module...............................................................................	28
Ozonator.......................................................................................................	28
NOx reaction cell ..........................................................................................	28
Converter ......................................................................................................	29
Main board....................................................................................................	29
Digital communications .........................................................................................	30
Setting the IP address ......................................................................................	30
Modbus over TCP/IP .........................................................................................	30
Analyzer fault register ................................................................................	30
Remote operation via VNC...............................................................................	32
Spare parts................................................................................................................	33
List of Figures
Figure 1 Functional pneumatics diagram ...........................................................	12
Figure 2 Home screen.............................................................................................	17
Figure 3 Home screen showing active alarm .....................................................	17
Figure 4 Home screen showing furnace and ozonator warnings...................	18
Figure 5 Home screen showing main menu choices.........................................	18
Figure 6 Calibration menu, for NOx1 gas............................................................	19
Figure 7 Numeric entry of calibration bottle value using pop-up keypad.....	19
Figure 8 Diagnostic screen....................................................................................	20
Figure 9 Trend screen.............................................................................................	20
Figure 10 Config screen: Sub-screens for further configuration....................	21
Figure 11 Analog output scaling screen ..............................................................	22
Figure 12 Analog output trim screen ...................................................................	22
Figure 13 IP address screen...................................................................................	23
Figure 14 QR code snapshot screen ....................................................................	23
Figure 15 About screen ..........................................................................................	24
Figure 16 Alarm screen, with one alarm cleared and two others active ........	24
Figure 17 Config alarm screen ..............................................................................	25

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List of Tables
	Table 1 I/O Analog output pin assignments (typical).......................................		14
	Table 2	Expected flows and temperatures during normal analyzer
		operation....................................................................................................	15
	Table 3	Analyzer fault register bit assignments ................................................	31
	Table 4 Modbus register map...............................................................................		31
	Table 5	Analyzer spare parts list...........................................................................	33

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Important precautions

Use dry, oil-free instrument air only

Caution: This instrument will be damaged if used with instrument air that is not completely dry and oilfree. Ensure instrument air has −40 °C dew point and has been filtered to remove all oil and particulates.

Safety notice

This instrument operates from potentially lethal line voltage. In addition, some internal components operate at high temperature and can cause serious burns. Observe all precautions when using this device, and particularly be sure that all devices connected to the instrument are safely wired and properly grounded. Always disconnect power to the instrument before opening the enclosure or servicing.

Caution: The analyzer should not be operated without the cover in place and the cooling fan fully operational.

The exterior surface of the converter furnace and tubes will rise to nearly 80 °C if operated without the cover in place. Serious burns can result if the proper precautions are not taken.

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Model CL3020 specifications

Performance specifications

	NOx	O2
Measurement technology	Chemiluminescence using	Amperometric Zirconium
	all solid-state detection	oxide cell
Measurement range	0 to 1000 ppm	0 to 25 % O2
Full scale range	Continuously adjustable	Continuously adjustable
	from 5 to 1000 ppm	from 5 to 25 % O2
Zero noise	< 0.04 PPM	< 0.02 % O2
Zero calibration drift	Better than ± 0.1 PPM	Better than ± 0.1 % O2
Span noise	< 0.25% of reading	< 0.02 %O2
Span calibration drift	Better than ± 1% of reading	Better than ± 0.1 % O2
Linearity error	< 2% of high calibration	< 1% of high calibration gas
	value across range from	value across range from
	zero to full scale1	zero to full scale1
Response time	T95 < 10 seconds	T95 < 10 seconds
NO2 converter efficiency	> 95%

Features

•Touch-screen interface: All diagnostics and controls are accessible through an advanced, full-color 5” touch screen interface.

•One-touch calibration: Once target gas values (e.g. bottle concentrations) have been entered, span and zero responses may be captured, and hence the analyzer calibrated, at the touch of the screen.

•Trend-screen: Gas concentrations are plotted in a chart-recorder style trend with user settable scales for in-depth data analysis at a glance.

•Diagnostics and alarms: Critical component temperatures and gas flows are measured within the analyzer and reported on the diagnostic screen. Target values and alarmable deviations are user-settable. These alarms are displayed on the home screen, as well as warning messages for internal communication errors or if the converter or ozonator has been disabled.

•Analog outputs: Each measurement, including dual ranges for NOx, is output as either 4-20mA or 0-10V (user selectable). Analog outputs can be forced to low (4mA/0V) or high (20mA/10V) for troubleshooting. Further, the gain and offset of these analog outputs may be trimmed within

1 Provided the calibration value is 80 to 100% of the full scale.

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approximately +/-5% of full scale to compensate for offsets or other issues with an external the data acquisition system, independent of analyzer calibration.

•QR code (2D barcode): Analyzer configuration and operating parameters, including calibration settings, can be sent via any mobile device that has a QR code / barcode scanning app for ease in remote troubleshooting and support.

•Digital communications: MODBUS over TCP/IP included, allowing access to gas concentrations, diagnostics, alarms, and other instrument parameters. The analyzer is also equipped with a VNC server that allows full remote operation from any device with a VNC viewer connected to the network. Using a locally connected PC or mobile device, factory personnel may remotely inspect and diagnose analyzer problems as if they were standing in front of the analyzer.

Mechanical specifications

•EIA 19-inch rack mount enclosure, 11 in. deep, 3 rack units tall (5.25 inches).

•Weight: 24 lbs.

•Power: 120VAC, 4 Amps max.

•Sample flow rate: Requires approximately 0.1 SLPM at atmospheric pressure (e.g. from a vented sample manifold) per NOx measurement channel

•Instrument air: Requires approximately 0.2 SLPM dry, instrument-quality, oil-free air at atmospheric pressure (e.g. from a vented manifold), per NOx measurement channel

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Overview

The Model CL3020 CLD NOx analyzer is designed specifically for use in lowNOx CEMS applications. NOx and NO (if dual-channel) are measured using chemiluminescence and a molybdenum-based NO2 converter for total NOx.

The Model CL3020 meets or exceeds 40CFR60 and 40CFR75 demands for relative accuracy, linearity, and calibration drift in low and ultra-low NOx gas-fired turbine applications.

Caution: The CL3020 is designed to analyze a clean, dry sample, as is typical of a conventional extractive CEMS. The sample dew point should be less than 5 C, and without any appreciable particulates or other condensable or reactive gases. As with all NOx analyzers, care should be taken in SCR applications to scrub any residual ammonia from the sample to avoid contamination of internal components.

Measurement configurations

The Model CL3020 has several different configurations:

1.Dual-ranging NOx, with or without O2. In this configuration, total NOx is measured using a molybdenum-based converter to convert any NO2 in the gas stream to NOx. Two separately calibratable NOx ranges are available, e.g full scales of. 100 PPM and 25 PPM, in addition to a single range output for O2.

2.Dual NOx (speciating), with or without O2. In this configuration, two independent chemiluminescence cells are used to simultaneously measure one converted stream (total NOx) and one unconverted stream (NO). The difference of these two is reported as NO2. This configuration may also be used with an external NH3 converter to measure total NOx plus NH3 on one channel, total NOx on the other channel, with the difference being NH3. A variety of analog output options are available in this configuration.

3.Enhanced performance for low range NOx, with or without O2. For full scales less than 200 PPM, greater sensitivity may be achieved with modified flows. Flows given in this manual are for standard configuration; consult factory for more information about flows in this configuration.

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Theory of operation

The Model CL3020 CLD NOx analyzer uses chemiluminescence as the fundamental detection mechanism for NOx measurement and a pumped (amperometric) zirconium oxide cell for the O2 measurement. A brief description of these mechanisms and their implementation in the analyzer are given below.

Chemiluminescence measurement of NOx

Chemiluminescence is defined as a chemical reaction that gives off light. Nitric oxide (NO) emits infrared light when it reacts with ozone (O3) to form NO2. By introducing a sample containing NO into a reaction cell and mixing it with ozone, one can measure the amount of light emitted by the ensuing reaction and can infer the amount of nitric oxide present in the original sample.

It is important to note that only NO is the only species directly measured. NOx, defined as the sum of NO and NO2 in a sample, is measured by first converting any NO2 to NO before it enters the measurement cell using a mo- lybdenum-based converter. If so equipped, NO only is measured in a second chemiluminescence cell from a sample that does not visit the converter.

Zirconium oxide measurement of O2

The oxygen measurement makes use of the fact that zirconium oxide conducts oxygen ions when heated above approximately 600 °C. Platinum electrodes on the interior and exterior of a zirconium oxide tube provide a catalytic surface for the exchange of oxygen molecules and oxygen ions. As molecules encounter the platinum electrodes, they become ionized and are transported through the body of the zirconium oxide. This charge transport ultimately establishes an electric potential across the electrodes that is proportional to the log of the ratio of oxygen concentrations on each side of the oxide (The Nernst Equation). Thus, if a reference gas (usually instrument air at 20.9 % O2) flows across the inner electrode, the concentration of sample gas flowing across the outer electrode can be determined. In a conventional zirconium-oxide oxygen analyzer, this voltage is exponentiated to determine the concentration.

In the Model CL3020, a second zirconium-oxide cell is ganged together to pump oxygen into the first cell, which is maintained at a constant voltage. The amount of oxygen needed to maintain the primary cell at the operating point is a more sensitive measurement of sample concentration, and allows for measurement at zero oxygen. This pump signal is carefully measured and related back to the sample concentration.

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Pneumatic design

Although the chemiluminescence technique is extraordinarily sensitive, specific to NOx, and inherently linear, there are many subtle effects involving pressures, flows, cell geometry, etc. that must be carefully engineered to produce a properly functioning analyzer. The pneumatic design of the Model CL3020 is shown in figure 1; the flow scheme is substantially different than other gas analyzers. To properly operate and service the analyzer, it is important that the flow scheme be well-understood.

Starting on the upper left side of the diagram, instrument air is drawn into the analyzer from a manifold vented to atmospheric pressure. Excess air flow should be available at this manifold to ensure integrity of instrument air to the analyzer. It is important that the air be free of oil and particulates. Ozone for the chemiluminescence reaction is produced in the ozonator, and is drawn into the cell where it mixes with the sample stream as described earlier. A flow-control orifice is embedded in the fitting on the ozone inlet(s) of the reaction cell(s), and the instrument vacuum pulls the proper flow through the ozonator.

Two sample channels, if so equipped, may be present on the analyzer. Excess sample flow should be available to each to ensure good sample integrity to the analyzer. A sample pump configured to deliver 1 SLPM under slight positive pressure to a 1/4" SwagelokTM tee connected to the analyzer, with a vent tube at least three feet long on each branch is an ideal connection.

Note: Under no circumstances should the sample inputs or ozone feed air be pressurized.

For the total NOx channel, the sample first flows through the converter where any NO2 is converted to NO, while any NO present is unaltered. The furnace temperature is displayed on the front panel of the analyzer. Next, this sample flows though the oxygen sensor (if so equipped), and then through the sample flow meter. This flow rate should approximately

70 SCCM. The sample then flows on to the reaction cell where it mixes with the ozone stream and the NOx measurement is performed. The reaction cell is kept at 40 °C.

The exhaust port of the reaction cell contains a critical flow orifice, which when backed by a sufficiently strong vacuum, controls the total flow drawn through the analyzer. Exhaust from the cell is routed through the high temperature furnace to destroy all the ozone in the exhaust stream to preserve the integrity of downstream components. Unlike carbon filters or other de-

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signs, this ozone destruction technique is very safe and effective. No measurable ozone is left in the exhaust. The analyzer is normally configured for an external pump to provide critical vacuum to pull the exhaust from the reaction cell. The flow through the analyzer is independent of this vacuum, provided it is low enough to meet the conditions for critical flow. The pressure on the downstream side of the critical flow orifice (measured under conditions of full analyzer flow) should be no more than 30% of atmospheric pressure.

If equipped, a second sample channel is present which does not flow through the converter, therefore measuring only NO. The difference between these two channels represents the NO2 concentration in the original sample, or any such other speciation (e.g. NH3) depending upon external system configuration.