Epson XDT manual Resetable Audio-Visual Alarm Option Nfpa compliant

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XDT User’s Manual

ber can be corrected by reversing the use of the UP and DOWN keys), with the “12” flashing. Pressing the “MODE” button will flash the next “0”. Pressing the “UP” button three times will display “1230”. Pressing the “MODE” button will flash the last “0”. Pressing the “UP” button four times will display “1234”. Pressing and holding the “MODE” button, will display “SET UN/ LOC”, indicating that the instrument is now unlocked. It may be locked without the password, same as any other instrument.

Note: To avoid unauthorized changes, it is imperative that instrument is returned into the locked mode.

11.Sensor Cable Compensation: As noted in other paragraphs this instrument measures the impedance of the sensor (in the form of attenuation in decibels) from which it computes the dewpoint. At very low dewpoints the sensor capacitance is small enough to be in the same order of magnitude as a long coaxial cable. Thus the measurement circuit must be compen- sated for the impedance of the sensor cable. Instruments which are delivered with a cable are already compensated at the factory and should not be compensated again, however if

anew cable is connected, the following procedure should be used for compensation (also refer to the Set-Up State flow diagram in Appendix A):

a.Disconnect the sensor from the cable by unplugging the BNC connector, keep the cable connected to the instrument.

b.Prepare a means by which the BNC connector at the end of the cable could be reliably shorted (using a jumper clip etc.), do not attempt to short at the instrument screw terminals as this approach will not account for the cable resistance.

c.Go to the CNF/CBL/OPN (Confirm Cable Open) mode.

d.Leave the BNC connector open and press the UP key. The instrument will show OPN and beep for a few seconds. Then it will show CNF/CBL/SHR (Confirm Cable Short).

e.Short the BNC connector and press the UP key, the unit will show SHR and beep for a few seconds. Then it will show CNF/CBL/OPN again.

f.Leave the BNC connector open again and press the UP button. The instrument will show OPN and beep for a few seconds. Then it will show END

The compensation data will be retained even if power is turned off.

3.5 Resetable Audio-Visual Alarm Option (NFPA compliant)

When the instrument is ordered with an Audio-Visual Alarm option, it is provided in the XDT- NEMA enclosure, outfitted with two front panel momentary push buttons in NEMA sealed rubber boots. The instrument complies with the recommendations of NFPA 99, 1996 edition.

•The alarm set point is programmed on a third alarm, hence the HI and LO alarm relays are free to be used for additional purposes The third alarm is properly configured to 39°F at the fac- tory, but when necessary may be modified by the user. Refer to the notes following HI & LO Alarms in the Flow Diagram of Operating State User Interface in appendix A.

•The visual indicator is the display backlight. When there is no alarm condition the LCD dis- play is not backlit but can still be easily and clearly read (in an extremely dark room the back- light may be momentarily turned on by pressing the TEST button). However as long as an alarm condition exists the LCD will be backlit in red. This lit-up front window of the instru- ment is the visual indicator.

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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 Installation & Sampling Techniques Sensor Technical SpecificationsNot Recommended In-situ InstallationExtractive Installation Mechanical Installation SAT Troubleshooting unexpected readingsElectromagnetic Compatibility Considerations Instrument Precautions using the XDTIsolation Instrument Technical SpecificationsXDT-NEMA IP65 Enclosure Installation InstallationInstrument Mechanical Installation XDT-PM DIN43700 Enclosure InstallationElectrical Connections Connecting PowerSensor Connection AC Mains Electrical Power ConnectionLow Voltage DC Powered Option Electrical Power Connection Wiring the Alarm ContactsInterfacing to the Analog Output Starting up Operating the InstrumentInterfacing to the RS-232 option Push Buttons Display Conventions12 3 4 5 6 7 8 Operating State Viewing Dewpoint ModeXDT User’s Manual Alarms Start Calibration HI **** ˚CSpanCheck Mode Single Point Self Calibration, manual or scheduled Instrument XDT User’s Manual SetUp State Viewing Serial Number ModeXDT 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 Sign on message Calibration without key press Appendix a Flow Diagram of Operating State User InterfaceHere 16.24˚C˚F Appendix B Flow Diagram of Set-Up State User InterfaceSensor Mechanical AppendixAppendix D Optional Sensor Fittings Side View Appendix E XDT Circuit Board DimensionsAppendix 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 Tested Instrument ˚C Appendix H Sample Gas Filter ConsiderationsSensor Appendix I XDT Grounding ConsiderationsAppendix J Analog Output vs. Dewpoint Instrument reading in ppmV Appendix K RS-232C Interface Protocol Help commandReceive Help Data Who Reset Login Data command K n m Error SensOpen or Error SensShort or Error SensSatLogin Command ? commandSerial Number Command Who CommandState User Interface Appendix L Procedure for Exchanging XDT SensorsAppendix M Uncertainty in LBS & ppmV calculations To obtain a RAN fill out this form and fax to 631 Xentaur Return Authorization Number Request FormPage Index Enclosure dimensions Pounds of H2O per million standard cubic Voltage, mains supply Iii Warranty
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