Epson manual Overview of the XDT

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Section 1: Introduction

1.0 Overview of the XDT

The XDT is a microprocessor based hygrometer, for measuring moisture content in gases in the range from -100°C to +20°C dewpoint depending on the sensor ordered. The XDT uses the Xen- taur Hyper Thin Film HTF™ sensor which is encapsulated in sintered stainless steel, thus it is capable of coming into contact with a wide variety of environments. However one should keep in mind that the sensor is a delicate device and it should be handled accordingly.

The measurement is displayed on the instrument’s custom LCD, can be transmitted by optional analog and digital outputs, and can control optional programmable relays. Four front panel but- tons provide the user with a rich feature set. The XDT’s advanced design allows it to be housed in a variety of enclosures.

The XDT has an impressive set of dewpoint measurement capabilities in terms of accuracy, stabil- ity, response time etc. The specifications of the sensor are discussed in section 2.2, while the spec- ifications of the instrument are discussed in section 3.2. A summary of the standard and optional features & capabilities of the XDT are listed below as an overview aid to the user.

Standard Features/Capabilities

Locking of instrument, preventing unintentional changes

SpanCheck™: - automatic recalibration using room air, all instruments pre-calibrated at fac- tory.

Capability to enter up to 15 NIST/NPL traceable calibration points at factory, depending on order.

Manual Self Calibration: a single point calibration using a known standard gas. High accuracy can be maintained even in the most harsh applications.

Pressure correction: built-in software calculation of dewpoint at a pressure different than the measurement.

Cable length compensation: user initiated automatic self measuring software.

Universal global autoranging AC supply 100-250VAC, 50/60Hz

Instrument and Sensor: UL & cUL listed/recognized; CE electromagnetic compatibility certi- fied

Optionally ordered Features/Capabilities

Password protected Locking of instrument, preventing unauthorized changes

Alarm Relays - programmable set points, error handling, and hysteresis. Up to 3 alarm relays may be ordered. On-display legends indicate relay states.

Audio Visual Alarm- complies with recommendations of NFPA 99, 1996 edition, audio reset and test buttons.

Analog Output- factory set voltage or user selectable 4/20 - 0/24 mA. Includes installation testing features. User selectable range (low & high point) of analog output.

RS-232C interface - allowing the user digital data access to the instrument.

Interval-timer-scheduled Self Calibration, a single point calibration using a known standard gas, can operate an electrically actuated switchover valve for unattended calibrations

Large variety of threads for sensor mounting into sample

Low voltage DC power operation 15-30VDC

Intrinsically Safe Approved NEC and CENELEC standards (UL & DEMKO) configurations

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Contents Yyyyyyy y Sensor Serial No Instrument Serial No XDT User’s Manual Iii XDT User’s Manual Table of Contents Index Overview of the XDT XDT User’s Manual Sensor and Sampling Techniques Precautions using the sensor Sensor Technical Specifications Sensor Installation & Sampling TechniquesIn-situ Installation Not RecommendedExtractive Installation Mechanical Installation Troubleshooting unexpected readings SATInstrument Precautions using the XDT Electromagnetic Compatibility ConsiderationsInstrument Technical Specifications IsolationInstallation Instrument Mechanical InstallationXDT-PM DIN43700 Enclosure Installation XDT-NEMA IP65 Enclosure InstallationConnecting Power Electrical ConnectionsAC Mains Electrical Power Connection Low Voltage DC Powered Option Electrical Power ConnectionWiring the Alarm Contacts Sensor ConnectionInterfacing to the Analog Output Starting up Operating the InstrumentInterfacing to the RS-232 option Push Buttons Display Conventions12 3 4 5 6 7 8 Viewing Dewpoint Mode Operating StateXDT User’s Manual Alarms HI **** ˚C Start CalibrationSpanCheck Mode Single Point Self Calibration, manual or scheduled Instrument XDT User’s Manual Viewing Serial Number Mode SetUp StateXDT User’s Manual Secured Password Protection Resetable Audio-Visual Alarm Option Nfpa compliant Troubleshooting the Instrument Display Explanation Required Action Maintenance XDT User’s Manual Glossary DB9 Glossary XDT User’s Manual Appendix a Flow Diagram of Operating State User Interface Sign on message Calibration without key pressHere Appendix B Flow Diagram of Set-Up State User Interface 16.24˚C˚FAppendix Sensor MechanicalAppendix D Optional Sensor Fittings Appendix E XDT Circuit Board Dimensions Side ViewAppendix E XDT-PM Enclosure Mounting Dimensions Appendix E XDT-NEMA Enclosure Mounting Dimensions Appendix F Sensor/SpanCheck Theory of Operation Appendix G Dewpoint Response time Analysis XDT User’s Manual Appendices Appendix H Sample Gas Filter Considerations Tested Instrument ˚CAppendix I XDT Grounding Considerations SensorAppendix J Analog Output vs. Dewpoint Instrument reading in ppmV Appendix K RS-232C Interface Protocol Help commandReceive Help Data Who Reset Login Data command Error SensOpen or Error SensShort or Error SensSat K n m? command Serial Number CommandWho Command Login CommandAppendix L Procedure for Exchanging XDT Sensors State User InterfaceAppendix M Uncertainty in LBS & ppmV calculations Xentaur Return Authorization Number Request Form To obtain a RAN fill out this form and fax to 631Page Index Enclosure dimensions Pounds of H2O per million standard cubic Voltage, mains supply Iii Warranty