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Shutdown Procedure, cooled laser, fill the laser dewar

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TGA Series Trace Gas Analyzers another absorption line. A persistent trend over time in the DC current may indicate premature aging of the laser. 3. Record the reference transmittance and compare it to previously recorded values. A change in the reference transmittance may indicate a problem with the reference gas supply. It can also be caused by a shift to a different absorption line, or a change in the pressure or temperature in the sample cell. 4. Record the sample pressure and compare it to previously recorded values. If the TGA sample pressure is actively controlled by the datalogger, a change in the pressure indicates a problem with the flows and pressures in the sampling system. If the pressure is not actively controlled it will be determined by the sample flow and the pump capacity. In this case, the pressure will decrease over time as the sample intake filter(s) becomes plugged. 5. If the TGA is equipped with a LN2 cooled laser, record the laser heater voltage and compare it to previously recorded values. The vacuum inside the laser dewar will gradually degrade. This degradation reduces the thermal isolation between the outer wall of the laser dewar and the laser itself. Over time, as more heat is transferred to the laser by the degraded vacuum, less heat is needed to maintain the laser at the set temperature, and the laser heater voltage will gradually decrease. Therefore, monitoring the laser heater voltage may give an indication of when it is time to evacuate the dewar. If the TGA is equipped with a TE-cooled laser, record the laser cooler voltage. 6. Verify that the concentration and concentration noise are as expected. 7. If the TGA is equipped with a LN2-cooled laser, fill the laser dewar with liquid nitrogen as needed. If the TGA is equipped with LN2cooled detectors, fill the detector dewar as needed. 8. Check the reference gas tank and regulator pressure. Check other tanks (air gap purge, calibration, etc.) as needed. Monitor the change in pressure as these gases are consumed, to gauge when to order replacement tanks and to identify possible leaks. 7.1.3 Shutdown Procedure This section describes the routine shutdown procedure for the TGA. 1. If a PC is connected to the TGA, turn off data collection if data is being collected, and quit the TGA program. 2. Shut off the TGA sample pump (and bypass pump, if applicable). 3. Shut off power to the TGA. 4. Shut off reference gas supply. 5. Shut off air gap purge supply, if applicable. 6. Shut off calibration gas supplies, if applicable. 48

Section	Page
Revision and Copyright Information	1
Limited Warranty	3
Assistance	4
Precautions	5
Table of Contents	7
1. Introduction	15
2. Cautionary Statements	16
3. Initial Inspection	17
4. Overview	17
4.1 System Components	20
4.1.1 Standard Components	21
4.1.1.1 TGA Power Module	21
4.1.1.2 TGA Accessory & Tool Kit	22
4.1.1.3 TGA Test Intake	22
4.1.1.4 TGA Leak Check Nozzle	22
4.1.1.5 TGA SDM Cable	23
4.1.1.6 Plastic Tubing	23
4.1.1.7 CAT5 Ethernet Crossover Cable	23
4.1.1.8 Serial Data Cable	24
4.1.1.9 TGA TEC Support Software and Operating System	24
4.1.2 Optional Components	25
4.1.2.1 Laser	25
4.1.2.2 AC Mains Power Cord	25
4.1.2.3 Power Module Mounting Brackets	26
4.1.3 Common Accessories	26
4.1.3.1 TGA Reference Gas Connection	26
4.1.3.2 TGA Insulated Enclosure Cover	27
4.1.4 Other Accessories	28
4.1.4.1 TGA Air Sample Intake	28
4.1.4.2 TGA Heated Intake Filter & Orifice	28
4.1.4.3 TGA High-Flow Filter Holder	28
4.1.4.4 Sample Vacuum Pump	29
4.1.4.5 Bypass Vacuum Pump	31
4.1.4.6 Sample Air Dryer	32
4.1.4.7 TGA Rotameter	35
4.1.5 Support Software	36
4.1.6 Replacement Parts	36
4.1.6.1 TGA Heated Intake Filter	36
4.1.6.2 Filter Element	36
4.1.6.3 TGA Filter Elements, 47mm (Qty 100)	37
4.2 Theory of Operation	37
4.2.1 Optical System	37
4.2.2 Laser	39
4.2.3 Dewars	39
4.2.4 Detectors	39
4.2.5 Laser Scan Sequence	40
4.2.6 Concentration Calculation	41
5. Specifications	42
5.1 Measurement Specifications	42
5.2 Physical Specifications	43
5.3 Power Requirements	43
6. Installation	44
6.1 Analyzer Installation	45
6.1.1 Plumbing Connections	47
6.1.2 Data Output Connections	49
6.1.3 Power	51
6.2 TGA Software Installation	53
6.2.1 Installation of PC Software	53
6.2.2 Updating TGA Operating System	54
6.2.3 Configure Ethernet Connection	56
6.2.4 Set TGA Serial Number and Identification String	59
6.2.5 Run the PC Software	60
6.3 Detailed Setup Instructions	60
7. Operation	60
7.1 Routine Operation	60
7.1.1 Startup Procedure	60
7.1.2 Routine System Checks	61
7.1.3 Shutdown Procedure	62
7.2 Software User Interface	63
7.2.1 Connect Window	63
7.2.2 Status Window	65
7.2.3 Settings Window	66
7.2.3.1 Laser	67
7.2.3.2 Detectors	73
7.2.3.3 Calculations	75
7.2.3.4 Other	80
7.2.4 Laser Window	84
7.2.4.1 View Less/View More	85
7.2.4.2 Tabbed/Expand	86
7.2.4.3 Display Mode	87
7.2.4.4 Colors	95
7.2.5 Find	95
7.2.6 Graph	98
7.2.7 Data	101
7.2.8 Files	102
7.3 Data Output	104
7.3.1 SDM Output	104
7.3.1.1 Syntax	105
7.3.1.2 Remarks	105
7.3.2 TGA Output to PC	108
7.3.3 TGA Analog Outputs	108
8. Troubleshooting and Maintenance	108
8.1 Lasers and Detectors	108
8.2 Reference Gas	109
8.3 Filtration and Sample Cell Cleaning	109
8.4 Sample Pumps	109
Appendix A. Configuring TGAs for Specific Gas Species	111
A.1 Laser Selection	111
A.1.1 LN2-cooled lasers	111
A.1.2 TE-cooled Lasers	111
A.1.3 Dewar Cables	112
A.1.4 Changing Lasers	112
A.2 Reference Gas	114
A.3 Detectors	116
A.4 Finding the Absorption Line	116
A.5 Air Gap Purge	117
Appendix B. Optical Alignment	119
B.1 Optical Alignment of TGA100 and TGA100A	119
B.1.1 Initial Alignment	122
B.1.2 Horizontal and Vertical Alignment	123
B.1.3 Focus Adjustment	124
B.1.4 Reference Detector Coalignment	125
B.2 Optical Alignment of TGA200 and TGA200A	125
B.2.1 Configure the TGA PC Software	127
B.2.2 Initial Alignment	127
B.2.3 Horizontal and Vertical Alignment	130
B.2.4 Focus Adjustment	131
Appendix C. Optimizing Laser Parameters	133
C.1 Laser Temperature	133
C.2 Zero Current	137
C.3 High Current	139
C.3.1 High Current Count	142
C.4 Omitted Data Count	143
C.5 Modulation Current	143
C.6 Laser Maximum Temperature and Laser Maximum Current	144
C.7 Laser Multimode Correction	144
Appendix D. Optimizing Detector Parameters	147
D.1 Detector Gain and Offset	147
D.2 Detector Preamp Gain	147
D.3 Detector Temperature	147
D.4 Detector Linearity Coefficients	148
Appendix E. Calibration	151
Appendix F. TGA Frequency Response	153
F.1 Measurement Rate	153
F.2 Sample Rate	153
F.3 Digital Filters	154
F.4 Synchronicity	156
F.5 Sample Cell Residence Time	157
Appendix G. Using Swagelok® Fittings	159
G.1 General Notes	159
G.2 Assembly	159
G.3 Common Replacement Parts	160
Appendix H. Upgrading Early Generation TGAs to TE-cooled Laser	163
H.1 TGA200	163
H.1.1 Basic Upgrade	163
H.1.2 Detectors	166
H.1.3 Power Module	166
H.1.4 Purge Boot	166
H.2 TGA100A	166
H.2.1 Basic Upgrade	166
H.2.2 Detectors	167
H.2.3 Holes in Enclosure for Cryocooler Refrigerant Tubes	167
H.2.4 Temperature Control Upgrade	167
H.2.5 Power Module	168
H.2.6 Purge Boot	168
H.3 TGA100	168
H.3.1 Basic Upgrade	168
H.3.2 CPU Module	168
H.3.3 Input and Output Modules	168
H.3.4 Detectors and Detector Cables	169
H.3.5 Temperature Controller	171
Appendix I. Install Temperature Control Upgrade	173
I.1 Install Thermistor Probes	173
I.2 Connect the Control Cable	175
I.3 Enter Control Parameters	176
I.4 Testing	176
I.1 Operation	177

Match case Limit results 1 per page

TGA Series Trace Gas Analyzers

another absorption line.

A persistent trend over time in the DC

current may indicate premature aging of the laser.

Record the reference transmittance and compare it to previously

recorded values.

A change in the reference transmittance may

indicate a problem with the reference gas supply.

It can also be

caused by a shift to a different absorption line, or a change in the

pressure or temperature in the sample cell.

Record the sample pressure and compare it to previously recorded

values.

If the TGA sample pressure is actively controlled by the

datalogger, a change in the pressure indicates a problem with the

flows and pressures in the sampling system.

If the pressure is not

actively controlled it will be determined by the sample flow and the

pump capacity. In this case, the pressure will decrease over time as

the sample intake filter(s) becomes plugged.

If the TGA is equipped with a LN

cooled laser, record the laser

heater voltage and compare it to previously recorded values.

The

vacuum inside the laser dewar will gradually degrade.

This

degradation reduces the thermal isolation between the outer wall of

the laser dewar and the laser itself.

Over time, as more heat is

transferred to the laser by the degraded vacuum, less heat is needed to

maintain the laser at the set temperature, and the laser heater voltage

will gradually decrease. Therefore, monitoring the laser heater

voltage may give an indication of when it is time to evacuate the

dewar. If the TGA is equipped with a TE-cooled laser, record the

laser cooler voltage.

Verify that the concentration and concentration noise are as expected.

If the TGA is equipped with a LN

-cooled laser, fill the laser dewar

with liquid nitrogen as needed.

If the TGA is equipped with LN

cooled detectors, fill the detector dewar as needed.

Check the reference gas tank and regulator pressure.

Check other

tanks (air gap purge, calibration, etc.) as needed.

Monitor the change

in pressure as these gases are consumed, to gauge when to order

replacement tanks and to identify possible leaks.

7.1.3 Shutdown Procedure

This section describes the routine shutdown procedure for the TGA.

If a PC is connected to the TGA, turn off data collection if data is

being collected, and quit the TGA program.

Shut off the TGA sample pump (and bypass pump, if applicable).

Shut off power to the TGA.

Shut off reference gas supply.

Shut off air gap purge supply, if applicable.

Shut off calibration gas supplies, if applicable.