Delta DO 9704 manual Classification of Pressure Measurements, Gauge

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ENGLISH

CLASSIFICATION OF PRESSURE MEASUREMENTS

Pressure measurements are relative and therefore refer to a reference pressure. There are four types of pressure measurement which enable the reference pressure to be defined immediately.

-Absolute pressure (A) – Pressure with respect to absolute zero, the ideal vacuum reference; the pressure measured is always higher than the reference pressure.

-Gauge (G) – Pressure measured with respect to atmospheric pressure, environment pressure is the reference; the pressure measured is always higher than the reference pressure.

-Vacuum (V) – Pressure with reference to atmospheric pressure, environment pressure is the reference; the pressure measured is always lower than the reference pressure.

-Differential pressure (D) – Pressure measured with respect to any reference pressure; the pres- sure measured may be higher or lower than the reference pressure.

Absolute	Relative	Differential
	(GAUGE)

Atmospheric pressure

VACUUM

											Zero
											pressure

Vacuum			P. to be								P. to be
			P. to be		Atm. P.						P. to be
			measured		Atm. P.						measured
			measured								measured

Absolute pressure A							Relative pressure (gauge) G
				Reference							P. to be


											measured
				P.							measured
The case G is similar to the case D
where the reference P = atmospheric P							Differential pressure D

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Contents Instructions Manual Page Pressure and Temperature DATA-LOGGER English Introduction Numbers Keyboard KEYREL Function DescriptionSimbols LIT Besides NumbersSimbols LIT Besides Function Numbers Description Tom of the displaySerial Output 600 Baud P0+Press the Prog key to move on to step P1 300 BaudP1+ = data dump This parameter is used for the fol- lowing two functions P1+Storage Hours minutes SecondsFunction P4+ = set year P3+P5+ = set month P6+ = set day P7+ = set hours P8+ = set minutes Self cut-out P9+Complete printing Reduced printing P10+To stop storage, press the Enter key P10+ Start-Stop P11+P11 Data CallChes itself off again Operating modeWhen this operative KEY Simbols LIT BesidesSimbols LIT Besides Function Numbers Description Enter If the battery symbol does not flaRestart it More than 30,000 acquisitionsAfter having taken note Probe Connection HOW to MeasureVarious operations Method of Using the Instrument and Warnings Temperature MeasurementLOU Instrument Signals and MalfunctionsErr FULLOW Battery Warning and Battery Replacement Serial Interface RS 232C Storage of the InstrumentDumping data from the memory Command Type ReplyParity None Bit Stop bit Protocol Xon/Xoff Type of terminalMemory clear Printer Diagram doExample of a Report Printed by the Instrument English Software connection with Windows Hardware connectionOK to confirm the setting one click Mark local Echo one click 100 101 102 Switch on the measuring instrument103 OK to confirm Cancel in the next window104 Parity None105 106 107 108 109 110 To end receiving data from an instrumentSelect END from the pull-down sub-menu one click To quit running the Hyper TerminalVdc=465.5 Calibrating the Instrument doFlow Rate Measurements Probe connection diagram Instrument do Connection of Probes to the Pressure Gauge Data Logger do113 Between 4 SEL R100 105 110 115 Turbine probe for measuring flow rateGauge Classification of Pressure MeasurementsConversion Factors and Tables = 2,491 x 102 Pa Psi = PaPsi = kPa = 3,386 x 103 Pa118 Minimum, Mean, Relative, A-B differential Instrument Technical DataConnector DIN 45326 8-pole Weight / dimensions 320 gr. / 215x73x38 mm120 121 Order Codes Guarantee 124 Examples of USE of the KeyboardSerial line Display blocked125 Pressing Data Call repeatedly givesInstrument programming 127 Sets yearSets day Sets hourData printing is reduced 128 Enables self cut-out +Normal operating Date and timeSerial output active Activation or disactivation of the serial outputActivation or disactivation of the Record function Function130 Activation and disactivation of the storage function131 Index132 EN61000-4-2, EN61010-1 level Safety