Epson manual Overview of the XDT

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

1