GE Druck DPI 740 User manual

GE
Sensing
Druck DPI 740
Precision Pressure Indicator
User Manual K0200

© The General Electric Company. All rights reserved

K200 Issue No. 1
i DPI 740 User Manual
Safety
The manufacturer has designed this instrument to be safe
when operated using the procedures detailed in this
manual. Do not use this instrument for any other purpose
than that stated.
This publication contains operating and safety
instructions that must be followed for safe operation and
to maintain the instrument in a safe condition. The safety
instructions are either warnings or cautions issued to
protect the user and the equipment from injury or
damage.
Use qualified* personnel and good engineering practice
for all procedures in this publication.
Pressure
Donotapplypressure greaterthanthemaximum safe working
pressure to the instrument.
Toxic Materials
There are no known toxic materials used in this instrument.
Maintenance
The instrument must be maintained using the manufacturer’s
procedures and should be carried out by authorised service
agents or the manufacturer’s service departments.
Technical Advice
For technical advice contact the manufacturer, agent or
subsidiary refer to the list at the rear of this manual.
* A qualified technician must have the necessary technical
knowledge, documentation, special test equipment and tools to carry
out the required work on this equipment.
This product meets the essential protection
requirements of the relevant EEC directives.
Further details of applied standards may be
found in the product specification.

DPI 740 User Manual ii
K200 Issue No. 1
Battery Safety
This instrument is fitted with three size AA batteries either
rechargeable (nickel cadmium) or non-rechargeable (alkaline).
Before storing this instrument remove the batteries.
When fitting batteries make sure the electrical contacts are
clean and observe the correct polarity.
The battery compartment should be inspected for corrsion
caused by leaking batteries. Corrosion must be removed using
approved methods*.
When storing and transporting batteries make sure that they
cannot be short circuited. A short circuited battery can
become very hot and can, in certain circumstances, explode.
It is recommended that a suitable container is used for storing
and transporting batteries.
Dispose of old batteries using a safe, approved method.*
*Refer to the Battery Manufacturer for this information.
Software Version
This manual contains operating instructions for instruments
with software version 1.XX. Further changes to the
instrument's software may require a change to the operating
instructions and an issue number change of the manual.

K200 Issue No. 1
iii DPI 740 User Manual
Abbreviations
The following abbreviations are used in this manual.
Note:
Abbreviations are the same in the singular and plural.
ABS acrylonitrile butadiene styrene
atm atmosphere
BS British standard
cmHg centimetre of mercury
CTS clear to send
DC direct current
DCE data circuit terminating equipment
DTE data terminal equipment
DUCI Druck Universal Communication Interface
ftH2Ofeetofwater
FS full-scale
hPa hecto Pascal
Hz Hertz
ICAO International Civil Aviation Organisation
i/d inside diameter
inHg inch of mercury
inH2Oinchofwater
ISA International standard atmosphere
kg kilogram
kgf/cm2kilogram forceper square centimetre
kgf/m2kilogram forceper square metre
kPa kilo Pascal
lbf/ft2pound force per square foot
LCD liquid crystal display
mA milli Ampere
mbar millibar
mbar a millibar absolute
mm millimetre
mmHg millimetre of mercury
mHg metre of mercury
MPa mega Pascal
mV millivolt

DPI 740 User Manual iv
K200 Issue No. 1
Abbreviations continued
Ni Cad nickel cadmium
o/d outside diameter
Pa Pascal
PCB printed circuit board
ppm parts per million
psi pound per square inch
QFE barometric pressure at airfield level (local)
QFF calculated sea level pressure including air temperature
QNH calculated sea level pressure
RPT resonant pressure transducer
RTS ready to send
RS232 Serial data communication standard
Rx receive
Tx transmit
VVolt
VA Volt amp
CdegreesCelsius
F degrees Fahrenheit
Symbols
The following symbols are used to identify hazards on this
instrument.
Static sensitive components handle with
extreme care.
Thissymbol,on theinstrument, indicates that
the user should refer to the user manual.

K200 Issue No. 1
v DPI 740 User Manual
Table of Contents
title page
1 Introduction .............................. ...............................................1
1.1 Specification.............................. ...............................................2
1.2 Accessories and Options...... ...............................................4
2 Installation................................. ...............................................5
2.1 Battery......................................... ...............................................5
2.2 Electrical Connections........... ...............................................6
2.3 Initial Settings............................ ...............................................10
3 Operation ................................... ...............................................11
3.1 General........................................ ...............................................11
3.2 Measurement Modes............. ...............................................11
Local (QFE) Measurement.... ...............................................13
Sea Level (QFF) Measurement ..........................................14
Altitude Measurement........... ...............................................16
Processing Measurements.. ...............................................18
Tare ............................................... ...............................................18
Filter .............................................. ...............................................18
Max/Min ...................................... ...............................................21
3.3 Set-up Menu.............................. ...............................................25
Battery......................................... ...............................................26
Units.............................................. ...............................................26
Time-out...................................... ...............................................28
Serial Communications........ ...............................................29
Entering a new PIN................. ...............................................31
Sending Measurements to a Printer or PC .................32
4 Calibration.................................. ...............................................33
Calibration Check.................... ...............................................33
5 Maintenance............................. ...............................................37
5.1 General........................................ ...............................................37
5.2 Fault finding............................... ...............................................37
5.3 Cleaning...................................... ...............................................37

DPI 740 User Manual vi
K200 Issue No. 1
Table of Contents (contd)
title page
6 Communications...................... .............................................. 39
6.1 Introduction................................ .............................................. 39
6.2 General Command Format. .............................................. 40
6.3 Command Summary.............. .............................................. 43
6.4 Command Set........................... .............................................. 45
Input Commands..................... .............................................. 45
Process Commands............... .............................................. 47
Set-up Commands.................. .............................................. 50
Calibration Commands......... .............................................. 51
Automatic Commands.......... .............................................. 55
Read Commands..................... .............................................. 56
Protocol Format Commands............................................ 58
Key Commands........................ .............................................. 59
Approved Service Agents...................... .............................................. 64
Table of Illustrations
fig. title page
1-1 General view.............................. .............................................. 1
2-1 Fitting the battery.................... .............................................. 6
2-2 Electrical connections........... .............................................. 8
2-3 Adaptor/charger connector 9
3-1 Instrument front panel.......... .............................................. 11
3-2 Measurement mode menu. .............................................. 12
3-3 Local pressure measurement ........................................ 13
3-4 Sea level measurement........ .............................................. 14
3-5 Altitude measurement.......... .............................................. 16
3-6 Process sub-menu.................. .............................................. 19
3-7 Max/Min menu.......................... .............................................. 22
3-8 Set-up menu.............................. .............................................. 25
3-9 Communications set-up....... .............................................. 30
3-10 Calibration................................... .............................................. 35

DPI 740 User Manual 1
K0200 Issue No. 1
1 Introduction
The Druck DPI 740 precision pressure indicator uses a silicon
resonant pressure transducer producing a pressure reading
in units of pressure measurement and altitude.
The instrument is contained in a moulded enclosure of a
composite ABS material and can be used as a hand-held
indicator or, using a retractable stand, as a bench instrument.
The instrument can also communicate, through a serial RS232
connector, with a compatible computer system or printer.
Figure 1-1 General view

K0200 Issue No. 1
2 D P I 7 4 0 U s e r M a n u a l
1.1 Specification
Dimensions
Weight: (nominal).................................................................. ..................0.5 kg
Size: height = 190 mm width = 90 mm, depth = 36 mm
Environmental
Temperature:
Operating.......................... ........ ......... ......... -10 to +50
 C
Storage ......................................................... ......... -40 to +70
 C
Pressure medium: ................ Any gas compatible with pyrex,
.................. .................. silicon, stainless steel and epoxy resin
Sealing standard................................................................... ..................IP54
Pressure
Connector...................................................... ......... 6 mm o/d
or.................................................... ......... 4 mm i/d hose fitting
Accuracy
Non-linearity, hysteresis and repeatability:
over the range of 10°to 30°C
........................................................................... ......... ±0.02 % FS
over the range of 0° to 40°C
........................................................................... ......... ±0.03 % FS
over the range of -10° to 50°C
........................................................................... .........±0.045 % FS
Stability .................................................................. ........ <100 ppm/year
Range (barometric)............................................ ........ 750 to 1150 mbar a
alternative ranges:
.................................................................. ........ 35 to 1300 mbar a
.................................................................. ........ 35 to 2600 mbar a
.................................................................. ........ 35 to 3500 mbar a
Maximum safe working pressure........................ ......... 4375 mbar a
Display
Read-out................................... .........999999 LCD digits, 13.6mm high
.................. .................. with additional 16 text characters
Overload indication
Error code flashing................. .........at nominal 110% FS
Response............................................ ........ nominal 2 readings/second
Resolution 0.01 mbar (e.g., 1013.25 mbar a)

DPI 740 User Manual 3
K0200 Issue No. 1
Specification (contd)
Electrical Power Supply
Batteries:...................................................... .........3 x 1.5 V alkaline size AA
Connections
external power adaptor/charger
.............................................. ......... International power jack
RS232 serial communications...................... ........ 6-way LEMO type
Electrical safety
This instrument meets:
............................ .........BS EN 61010 as applicable
Electromagnetic compatibility
This instrument meets:
........................................................ ......... EN50081-1 (emissions)
........................................................ ......... EN50082-1 (immunity)
Continuing development sometimes necessitates
specification changes.

K0200 Issue No. 1
4 D P I 7 4 0 U s e r M a n u a l
1.2 Accessories and Options
The instrument is delivered with the following:
Accessories
i. User manual K200 (this publication).
ii. Calibration certificate.
iii. Carrying case.
Options
A Enhanced barometric accuracy
over the range of 10  to 30  C
........................................................................... ......... ±0.15 mbar
B NiCad batteries and power adaptor/charger
Adaptor/charger
External Power
............................................... ........ 100 to 240 V a.c. (nominal)
.................................................................. ........ 10 VA, 47-65 Hz
Output
............................................... ........ 12 Vd.c., 800 mA (maximum)
Connection
............................................... ........ International power jack
C Adaptor cable
For RS232 connecting the 6-pin LEMO to standard
9-way D type.
DTransitcase

DPI 740 User Manual 5
K0200 Issue No. 1
2 Installation
WARNING:
DO NOT ATTEMPT TO CHARGE NON-RECHARGEABLE
BATTERIES. TO PREVENT ACCIDENTAL CHARGING OF NON-
RECHARGEABLE BATTERIES THE CHARGE LINK LK2 MUST BE
IN THE DISABLED POSITION ().
CAUTION:
DONOT LEAVE DISCHARGED BATTERIES IN THE INSTRUMENT.
OLD BATTERIES CAN LEAK AND CAUSE CORROSION.
WHEN FITTING THE BATTERIES MAKE SURE THE ELECTRICAL CONTACTS
ARE CLEAN AND OBSERVE THE CORRECT POLARITY.
Note:For further information, refer to the safety page at
the front of this manual and to the battery
manufacturer.
2.1 Battery (Figure 2-1)
Three batteries are fitted in the battery compartment.
For non rechargeable batteries make sure the charging link
LK2 is fitted in the disabled position ( ).
For rechargeable batteries make sure the charging link LK2
is fitted in the enabled position ().
Note:The charging link LK2 is located on the instrument
PCB. To access this link remove the top case
assembly.
To replace the batteries, unscrew the captive screw and slide
off the battery compartment cover. Make sure the polarity of
the new batteries is correct.
If the battery capacity is low the display shows:
The battery symbol (approximately 1 hour left).
The flashing message Battery Very Low for 15 to 20
minutes.
The message Batteries Dead! followed, after a shorttime,
Switching Off!! the instrument then automatically switches
off.

K0200 Issue No. 1
6 D P I 7 4 0 U s e r M a n u a l
Figure 2-1 Fitting the Battery
2.2 Electrical connections
(Figure 2-2 and 2-3)
The optional adaptor/charger is supplied with a set of
interchangeable connectors so that the unit can be used
worldwide. To change the power pin adaptor push the adaptor
from the charger body, align the replacement adaptor and
push onto the charger body.
Battery charger
This is a two-pole, 2.5 mm, centre pin connector:
-ve - centre pin.
+ve - outer connector casing.
captive
screw

DPI 740 User Manual 7
K0200 Issue No. 1
RS232 connections
Option C is the adaptor cable recommended for use with the
RS232 serial communication interface. The adaptor cable has,
at one end, 6-pin LEMO type connector and, at the other, a 9-
way D type connector. The instrument's serial communication
settings and the data terminal equipment (DTE) settings must
be the same. The recommended initial settings are as follows:
Baud rate - 9600
Data bits - 8
Stop bits - 1
Parity - none
Handshaking - none
Adaptor Cable
Notes
1. The function column for the D type connector uses RS232
terminology with respect to DTE.
2. In the D-type connector DTR and DSR should be connected
together as follows:
9-way pin 4 and 6
25-way pin 20 and 6
3. The instrument's serial communication settings can be
changed using the set-up menu.
Pin No. Function Flow Function
D type Connector
1
2
3
5
6
4
RxD input
CTS input
GND (screen)
not used
TxD output
RTS output
TxD
RTS
GND
-
RxD
CTS
3
7
5
-
2
8
25-way
9-way
Pin No. Pin No.
2
4
7
-
3
5
LEMO connector
Instrument (DCE) PC (DTE)

K0200 Issue No. 1
8 D P I 7 4 0 U s e r M a n u a l
Figure 2-2 Electrical connections

DPI 740 User Manual 9
K0200 Issue No. 1
Figure 2-3 Adaptor/charger connector
FOR ALL Druck
INSTRUMENTS
PART No. 191-129

K0200 Issue No. 1
1 0 D P I 7 4 0 U s e r M a n u a l
2.3 Initial Settings
The instrument is shipped with the following settings:
Standard Instrument Settings
Units of pressure measurement
(selected by F2)................................... ........ mbar, inHg, hPa
Battery charging link (LK2) .................................... ......... disabled ()
Calibration link (LK1)................................................... ......... disabled ()
PIN ..................................................................................... .................. 000
Time-out ................................................................ ........ enabled (1 minute)
Option B Instrument Settings
Units of pressure measurement
(selected by F2)................................... ........ mbar, inHg, hPa
Battery charging link (LK2)...................................... ......... enabled ()
Calibration link (LK1)................................................... ......... disabled ()
PIN ..................................................................................... .................. 000
Time-out enabled (1 minute)

DPI 740 User Manual 11
K0200 Issue No. 1
3Operation
3.1General (Figure 3-1)
The instrument is switched on by the ON/OFF push-button and
powers up in the last selected mode and units of
measurement. The instrument "times-out" after a period of
one minute if no push-button selections are made. To keep
the instrument in the powered-upstate the ON/OFFand MODE
push-buttons should be pressed together. The display briefly
shows a "Timeout Disabled" message. Pressing the MODE
push-button steps through the three pressure measurement
modes. Pressing the SET push-button steps through the set-
up menu (described in 3.3).
3.2Measurement Modes (Figure 3-1)
Selecting the MODE push-button, changes the measurement
mode between:
Local (QFE unprocessed pressure at the pressure port).
Sea (QFF calculated pressure at sea level).
Altitude (calculated height from pressure datum).
Selecting the push-button F2 changes the units of pressure
measurement, continuous pressing steps between three
preselected units, the display shows the units for each meas-
urement mode.
Figure 3-1 Instrument front panel
F1
SET
F2
MODE
tare
+
-
ON/OFF control
Set-up menus
low pass
filter
battery
condition
16 character
status line
selected
mode
mode selection
function selection
function
selection
selected
units

K0200 Issue No. 1
12 DPI 740 User Manual
Figure 3-2 Measurement mode menu
PROCESS
see figure 3-6
QFE - local pressure QFF - sea level pressure Altitude in feet and metres
LOCAL ALTITUDE
Change units
Change units
feet or metres
Change units
SEA
same as QFE
PROCESS SET_QFF
Enter Height ASL
HT=.....ft (or metres)
Enter Temp
STORE HEIGHT
STORE
TEMPERATURE
TEMP=<V> C
°
to QFE
SET_ALT
same as QFE
PROCESS
ISA -alt- USER
Pressure Datum
Dat.=1013.25 mbar
Enter Datum
STORE PRESSURE DATUM
Dat.=1013.25 mbar
F1 F1
F1
F1
F1
F1
F1
F1
F1
F2 F2 F2
F2
F2
F2
F2
F2
F2
SET
SET
SET
SET
MODE MODE MODE