Troubleshooting | Quantum Instruments Cascade Laser Starter Kit

Chapter 7

Troubleshooting

7.1Chapter overview

This chapter sets out troubleshooting instructions for ensuring safe and trouble-free operation of the Quantum Cascade Laser Starter Kit system.

7.2Principle

The personnel must have read and understood this documentation before carrying out any activity what- soever with the Quantum Cascade Laser Starter Kit. In case of unclear information, please contact the distributor.

The power supply reaches max cur- rent for a very low voltage

-The low impedance line or the QCL is shorted to ground.

√Check the cabling.

√Replace the laser if necessary.

-The DC power supply is NOT ﬂoating.

√Change the cabling in order to leave the laser ﬂoating.

-The laser tightening device is too tight- ened and the QCL laser is shorted to ground.

√Loose the laser ﬁxture device.

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Quantum Instruments Cascade Laser Starter Kit manual Troubleshooting, Principle, DC power supply is not ﬂoating

Contents

Quantum Cascade Laser Starter Kit Instructions Manual Web version Contents Installation TroubleshootingMaintenance Overview Use Appendix Identiﬁcation DocumentLimited waranty Manufacturer General Chapter overviewGeneralities Compliance Glossary PersonsProduct Personnel Commands style Procedure styleTypographic conventions Description style Problem Procedure eﬀects styleSee page x-y Troubleshooting style Possible causePage Safety Instructions Importance of safety instructionsNon-compliance with the safety regulations Introduction General safety instructions Environmental conditionsCompliance and informa- tion Description System Composition DFB and FP Quantum Cascade Lasers If no conﬁguration is speciﬁed, the DN pad is usedDescription Geometry of QC lasers Speciﬁcations Electrical model characteristics Electrical model Laboratory Laser HousingLLH100 LLH100 external view description Laboratory Laser Housing internal view LLH100 internal view Speciﬁcations of the Peltier connector Thermo-Electric Cooler TEC and PT100 connections Speciﬁcations of the measurement connector Measurement connection QCL pulser switching unitLDD100 QCL pulser switching unit front and rear view QCL pulse switching measuring unit GeneralitiesMeasured voltages Timing data Laser peak current Duty cycle calculation Laser peak voltage Average dissipationAccuracy considerations Trigger and logic output signals Ω TTL driver circuit QCL pulser timing unit TPG128 QCL temperature controllerTCU151 Peltier and PT100 connections Installation Chapter overview Packing listGeneral Standard items Setting the appropriate AC voltage on TCU151 Procedure110-120V, 60Hz USA 220-240V, 50Hz Europe Installing the starter Kit Before beginning Connecting Starter Kit Use QCL pulse timing unit com- mand description TCU151 command description TCU151 temperature controler front panel Laser utilisation OverviewProceedings Starting the TPG128 Procedure Interlock utilisation Interlock utilisation Troubleshooting Power supply reaches max cur- rent for a very low voltageDC power supply is not ﬂoating Principle Laser draws current but gives no light Laser does not draw currentQCL laser is not used with the LLH and is grounded There is no contact with the laser Maintenance How to remove the covers of TCU151 and TPG128Overview Replacement procedures Quantum Cascade Laser replace Ment Facet on the case, it is extremely fragile + LLH100 connection QCL UP and DN position Exchange Exchanging the laser If the ambient atmosphere is humid this is Humidity TCU151 temperature con Troller interlock setting Procedure interlock settingBefore beggining interlock set Ting Needed material Calibaration procedures Procedure calibration1 TPG128 calibration Generalities TPG128 main board TPG128 main board 2 TCU151 temperature controller calibration Procedure +5V/-5V power supply check Sensing level and range adjustement = 1.22 to Temperature Reference oﬀset adjustment Current/Voltage ratio adjustment SettingOscillator check LCD screen should display 1.00 a 7V = 70 C If needed, adjust it with the trimmer P92 Starting the power section of the instru Ment Current adjustment → Value displayed ≤ 1A→ Value displayed should tend to the deﬁned value Miscellaneous functions testing Temperature Limit testing → The temperature displayed 2 should be 035 CThreshold on → The red LED 1 should turn oﬀ Application notes Detection techniquesDirect absorption Frequency modulation technique Tildas Photoacoustic detection Photoacoustic technique Appendix Bias Circut Bias-TGeneral Utilisation What has to be kept in mind before use? Current and voltage ranges of the Bias-T cir- cuit Avoid reverse polarity on the input Unpacking NS laser from its transportation box Unpacking instructions for NS submounts