Endress+Hauser Deltabar FMD72 Manual

Electronic differential pressure transmitter with ceramic and metal sensors
Application
The Deltabar FMD71/FMD72 is used to measure the level,
volume or mass of liquids in pressurized and vacuum vessels.
Your benefits
The electronic differential pressure system eliminates
traditional mechanical issues resulting in greater process
availability and reliability
• Safety risks are minimized with the electronic differential
pressure system architecture and design
• Lowest total cost of ownership due to reduced installation
time, maintenance, downtime and spare requirements,
downtime and spare requirements.
• Multivariable level measurement: HART-based differential
pressure, head pressure and sensor temperatures from one
system
• Continuous health indication of the entire system via HART-
based diagnostic
• High reproducibility and long-term stability
• Overload-resistant and function-monitored
Products Solutions Services
Technical Information
Deltabar FMD71, FMD72
Level measurement with electronic differential pressure
TI01033P/00/EN/04.14
71243971

Deltabar FMD71, FMD72
2 Endress+Hauser
Table of contents
Document information ....................... 4
Document function ............................ 4
Symbols used ................................ 4
Documentation ............................... 5
Terms and abbreviations ........................ 6
Function and system design ................... 7
Measuring principle - electronic differential pressure
measurement ................................ 7
Measuring system ............................. 8
System integration ............................ 9
Input .................................... 10
Measured variable ............................ 10
FMD71: measuring range of individual sensors ......... 10
FMD72: measuring range of individual sensors ......... 11
Output .................................. 12
Output signal ............................... 12
Signal range – 4 to 20 mA HART .................. 12
Signal on alarm .............................. 12
Maximum load .............................. 12
Dead time, time constant ....................... 13
Dynamic behavior, current output .................. 13
Dynamic behavior, HART ....................... 13
Damping .................................. 13
Alarm current ............................... 13
Firmware Version ............................ 13
Protocol-specific data .......................... 14
Power supply ............................. 15
Terminal assignment .......................... 15
Supply voltage .............................. 15
Cable specification for transmitter connection .......... 16
Cable entries ............................... 16
Residual ripple .............................. 16
Influence of power supply ....................... 16
Overvoltage protection ......................... 16
Performance characteristics - general .......... 17
Reference operating conditions ................... 17
Measuring uncertainty for small absolute pressure
measuring ranges ............................ 17
Resolution ................................. 17
Influence of the installation position ................ 17
Warm-up period ............................. 17
Vibration effects ............................. 18
Application limits ............................ 18
Performance characteristics - devices with
ceramic process isolating diaphragm ........... 19
FMD71 reference accuracy ...................... 19
Thermal change of the zero output and the output span
for FMD71 ................................. 20
FMD71 total performance ....................... 21
FMD71 long-term stability ...................... 22
FMD71 total error ............................ 22
Performance characteristics - devices with metal
process isolating diaphragm .................. 23
FMD72 reference accuracy ...................... 23
Thermal change of the zero output and the output span
for FMD72 ................................. 23
FMD72 total performance ....................... 24
FMD72 long-term stability ...................... 24
FMD72 total error ............................ 24
Installation ............................... 25
Mounting location ............................ 25
Orientation ................................ 25
General installation instructions ................... 25
Thermal insulation - FMD71 high-temperature version ... 25
Installing the sensor modules .................... 26
Installing the transmitter ....................... 26
Sensor and transmitter cable ..................... 27
Environment .............................. 28
Ambient temperature range ..................... 28
Storage temperature range ...................... 28
Climate class ............................... 28
Degree of protection .......................... 28
Vibration resistance ........................... 28
Electromagnetic compatibility .................... 28
Process .................................. 29
FMD71 process temperature limits ................. 29
FMD72 process temperature limits ................. 29
Pressure specifications ......................... 30
Mechanical construction .................... 31
Device height ............................... 31
T14 transmitter housing (optional display on the side) .... 32
In preparation - T17 transmitter housing (optional display
on the side) ................................ 32
Sensor housing .............................. 33
FMD71 process connections, internal process isolating
diaphragm ................................. 33
FMD71 process connections, internal process isolating
diaphragm ................................. 34
FMD71 process connections, internal process isolating
diaphragm ................................. 35
FMD71 process connections, flush-mounted process
isolating diaphragm ........................... 36
FMD71 process connections, flush-mounted process
isolating diaphragm ........................... 37
FMD71 process connections, flush-mounted process
isolating diaphragm ........................... 38
FMD71 process connections, flush-mounted process
isolating diaphragm ........................... 39
FMD71 process connections, flush-mounted process
isolating diaphragm ........................... 42
FMD71 process connections, flush-mounted process
isolating diaphragm ........................... 43
FMD72 process connections, internal process isolating
diaphragm ................................. 44

Deltabar FMD71, FMD72
Endress+Hauser 3
FMD72 process connections, internal process isolating
diaphragm ................................. 45
FMD72 process connections, flush-mounted process
isolating diaphragm ........................... 46
FMD72 process connections, flush-mounted process
isolating diaphragm ........................... 47
FMD72 process connections, flush-mounted process
isolating diaphragm ........................... 48
FMD72 process connections, flush-mounted process
isolating diaphragm ........................... 49
FMD72 process connections, flush-mounted process
isolating diaphragm ........................... 50
Wall and pipe mounting with mounting bracket ........ 53
Materials in contact with process .................. 54
Materials not in contact with process ............... 55
Operability ............................... 58
Operating concept ............................ 58
Local operation .............................. 58
Operating languages .......................... 60
Certificates and approvals ................... 61
CE mark ................................... 61
Ex approvals ................................ 61
Suitability for hygienic processes (in preparation) ....... 61
Pressure Equipment Directive (PED) ................ 61
Other standards and guidelines ................... 61
CRN approval ............................... 61
Classification of process sealing between electrical
systems and (flammable or combustible) process fluids in
accordance with ANSI/ISA 12.27.01 ................ 62
Calibration unit .............................. 62
Calibration ................................. 62
Test, certificate .............................. 62
Ordering information ....................... 63
Documentation ............................ 63
Field of Activities ............................ 63
Technical Information ......................... 63
Operating Instructions ......................... 63
Description of device parameters .................. 63
Brief Operating Instructions ..................... 63
Safety Instructions (XA) ........................ 63
Registered trademarks ...................... 64
HARTâ................................... 64

Deltabar FMD71, FMD72
4 Endress+Hauser
Document information
Document function The document contains all the technical data on the device and provides an overview of the
accessories and other products that can be ordered for the device.
Symbols used Safety symbols
Symbol Meaning
DANGER
A0011189-EN
DANGER!
This symbol alerts you to a dangerous situation. Failure to avoid this situation will result in
serious or fatal injury.
WARNING
A0011190-EN
WARNING!
This symbol alerts you to a dangerous situation. Failure to avoid this situation can result in
serious or fatal injury.
CAUTION
A0011191-EN
CAUTION!
This symbol alerts you to a dangerous situation. Failure to avoid this situation can result in
minor or medium injury.
NOTICE
A0011192-EN
NOTICE!
This symbol contains information on procedures and other facts which do not result in
personal injury.
Electrical symbols
Symbol Meaning
A0011197
Direct current
A terminal to which DC voltage is applied or through which direct current flows.
A0011198
Alternating current
A terminal to which alternating voltage is applied or through which alternating current flows.
A0017381
Direct current and alternating current
• A terminal to which alternating voltage or DC voltage is applied.
• A terminal through which alternating current or direct current flows.
A0011200
Ground connection
A grounded terminal which, as far as the operator is concerned, is grounded via a grounding
system.
A0011199
Protective ground connection
A terminal which must be connected to ground prior to establishing any other connections.
A0011201
Equipotential connection
A connection that has to be connected to the plant grounding system: This may be a potential
equalization line or a star grounding system depending on national or company codes of practice.
Symbols for certain types of information
Symbol Meaning
A0011182
Permitted
Indicates procedures, processes or actions that are permitted.
A0011183
Preferred
Indicates procedures, processes or actions that are preferred.
A0011184
Forbidden
Indicates procedures, processes or actions that are forbidden.
A0011193
Tip
Indicates additional information.

Deltabar FMD71, FMD72
Endress+Hauser 5
Symbol Meaning
A0011194
Reference to documentation
Refers to the corresponding device documentation.
A0011195
Reference to page
Refers to the corresponding page number.
A0011196
Reference to graphic
Refers to the corresponding graphic number and page number.
A0015502
Visual inspection
Symbols in graphics
Symbol Meaning
1, 2, 3 ... Item numbers
,… ,
Series of steps
A, B, C, ... Views
A-A, B-B, C-C, ... Sections
-
A0011187
Hazardous area
Indicates a hazardous area.
.
A0011188
Safe area (non-hazardous area)
Indicates the non-hazardous area.
Documentation The document types listed are available:
• On the CD supplied with the device
• In the Download Area of the Endress+Hauser Internet site: www.endress.com → Download
Brief Operating Instructions KA01105P: getting the 1st measured value quickly
The Brief Operating Instructions contain all the essential information from incoming acceptance to
initial commissioning.
Operating Instructions BA01044P: your comprehensive reference
These Operating Instructions contain all the information that is required in various phases of the life
cycle of the device: from product identification, incoming acceptance and storage, to mounting,
connection, operation and commissioning through to troubleshooting, maintenance and disposal.
Description of Device Parameters GP01013P: reference for your parameters
The document provides a detailed explanation of each individual parameter in the operating menu.
The description is aimed at those who work with the device over the entire life cycle and perform
specific configurations.
Safety Instructions (XA)
Safety Instructions (XA) are supplied with the device depending on the approval. These instructions
are an integral part of the Operating Instructions.
Device Certificate/type of protection Documentation Version 1)
FMD71, FMD72 ATEX II 1/2G Ex ia IIC T6 Ga/Gb XA00619P BA
FMD71, FMD72 ATEX II 1/2G Ex d [ia] IIC T6 Ga/Gb XA00620P BC
FMD71, FMD72 ATEX II 3G Ex nA IIC T6 GC XA00621P BD
FMD71, FMD72 IEC Ex ia IIC T6 Ga/Gb XA00622P IA
FMD71, FMD72 IEC Ex d [ia] IIC T6 Ga/Gb XA00623P IB
FMD71, FMD72 CSA General Purpose - CD

Deltabar FMD71, FMD72
6 Endress+Hauser
Device Certificate/type of protection Documentation Version 1)
FMD71 FM C/US IS Cl.I Div.1 Gr.A-D, AEx ia, Zone 0,1,2 XA00628P FA
FMD71 FM C/US XP AIS Cl.I Div.1 Gr.A-D, Exd [ia] Zone 0,1,2 XA00629P FB
FMD71 CSA C/US XP Cl.I Div.1 Gr.A-D, Ex d [ia], Zone 0,1,2 XA00631P CB
FMD71 FM C/US NI Cl.I Div.2 Gr.A-D, Zone 2 XA00668P FD
FMD71 CSA C/US NI, Cl.I Div. 2, Gr.A-D Cl.I, Zone 2, IIC XA00670P CC
FMD71 CSA C/US IS Cl.I Div.1 Gr.A-D, Ex ia Zone 0,1,2 XA00630P CA
FMD72 CSA C/US IS Cl.I Div.1 Gr.A-D, Ex ia Zone 0,1,2 XA00626P CA
FMD72 CSA C/US XP Cl.I Div.1 Gr.A-D, Ex d [ia], Zone 0,1,2 XA00627P CB
FMD72 CSA C/US NI, Cl.I Div.2 Gr.A-D, Zone 2 XA00671P CC
FMD72 FM C/US IS Cl.I Div.1 Gr.A-D, AEx ia, Zone 0,1,2 XA00624P FA
FMD72 FM C/US XP AIS Cl.I Div.1 Gr.A-D, Exd [ia] Zone 0,1,2 XA00625P FB
FMD72 FM C/US NI Cl.I Div.2 Gr.A-D, Zone 2 XA00669P FD
1) Product Configurator, "Approval" section
The nameplate provides information on the Safety Instructions (XA) that are relevant for the
device.
Terms and abbreviations
Term/abbreviation Explanation
MWP The MWP (maximum working pressure) for the individual sensors depends on the lowest-rated
element, with regard to pressure, of the selected components, i.e. the process connection has to be
taken into consideration in addition to the measuring cell. Also observe pressure-temperature
dependency. For the relevant standards and additional notes, see the "(→  30)" section.
OPL The OPL (over pressure limit = sensor overload limit) for the measuring device depends on the
lowest-rated element, with regard to pressure, of the selected components, i.e. the process
connection has to be taken into consideration in addition to the measuring cell. Also observe
pressure-temperature dependency. For the relevant standards and additional notes, see the
"(→  30)" section.
LRL Lower range limit
URL Upper range limit
LRV Lower range value
URV Upper range value
TD Turn down
Set span and zero-based span
½Lower range value (LRV) ½ < ½ Upper range
value (URV)½
Example with measuring cell
HP = 1 000 mbar (15 psi) and measuring cell
LP = 400 mbar (6 psi):
LRL = 400 mbar (6 psi):
• Lower range value (LRV)
=–300 mbar (–4.35 psi)
• Upper range value (URV) = 0 mbar
• Nominal value (URL) =1 000 mbar (15 psi)
Turn down:
TD = URL + ½LRL½/½ URV - LRV ½ 4.66:1
Set span:
URV – LRV =300 mbar (4.35 psi)
This span is based on the zero point.
LRV URLURV LRL
1 = 2
3
4
5
A0016451
1 Set span
2 Zero-based span
3 Nominal value Upper range limit (URL)
4 Nominal measuring range
5 Sensor measuring range

Deltabar FMD71, FMD72
Endress+Hauser 7
Function and system design
Measuring principle -
electronic differential
pressure measurement
FMD71 with ceramic process isolating diaphragm (Ceraphire®)
The ceramic sensor is a dry sensor, i.e. the process pressure acts directly on the robust ceramic
process isolating diaphragm and causes it to deflect. A pressure-dependent change in capacitance is
measured at the electrodes of the ceramic support and the process isolating diaphragm. The
measuring range is determined by the thickness of the ceramic process isolating diaphragm.
Advantages:
• Guaranteed overload resistance up to 40 times the nominal pressure
• The ultrapure 99.9 % ceramic (Ceraphire®, see also "www.endress.com/ceraphire") ensures:
– Excellent chemical resistance properties, comparable with Alloy C
– Less relaxation
– High mechanical stability
• Can be used in absolute vacuum
• Outstanding surface finish, Ra ≤ 0.3 µm (11.8 µin)
1234
p
A0020465
1 Air pressure (relative pressure sensors)
2 Ceramic support
3 Electrodes
4 Ceramic process isolating diaphragm
FMD72 with metal process isolating diaphragm
The process pressure deflects the metal process isolating diaphragm of the individual sensors and a
fill fluid transfers the pressure to a resistance bridge (semiconductor technology) within the compact
sensor. The pressure-dependent change in the bridge output voltage is measured and evaluated.
Advantages:
• Can be used for process pressures up to 40 bar (600 psi).
• High long-term stability
• Guaranteed overload resistance up to 10 times the nominal pressure
• Significantly less thermal effect compared to diaphragm seal systems with capillaries
p
1
2
3
4
A0016448
1 Silicon measuring element, substrate
2 Wheatstone bridge
3 Channel with fill fluid
4 Metal process isolating diaphragm

Deltabar FMD71, FMD72
8 Endress+Hauser
Measuring system The FMD71/FMD72 consists of 2 sensor modules and one transmitter. One sensor module measures
the hydrostatic pressure (high pressure) and the other one the head pressure (low pressure). The
level (electronic differential pressure) is calculated in the transmitter using these two digital values.
Device features
FMD71 FMD72
Field of
application
• Level
• Differential pressure
Process
connections
• Thread
• EN and ANSI flanges
• Flush-mounted hygienic connections
• Thread
• EN and ANSI flanges
• Flush-mounted hygienic connections
Measuring ranges
(differential
pressure)
from
–100 to +100 mbar (–1.5 to +1.5 psi)
to–1 to +40 bar (–15 to +600 psi)
from –400 to +400 mbar (–6 to +6 psi)
to–1 to +40 bar (–15 to +600 psi)
MWP 1) to60 bar (900 psi) to160 bar (2 400 psi)
Process
temperature limits
–25 to +150 °C (–13 to +302 °F) –40 to +125 °C (–40 to +257 °F)
Higher process temperature limits available on
request (up to +250 °C (480 °F))
Ambient
temperature
range
–40 to +80 °C (–40 to +176 °F)
Reference
accuracy of the
individual sensors
• Up to ±0.075 % of the set span
• PLATINUM version: up to ±0.05 % of the set span
Supply voltage • Version for non-hazardous areas: 12 (13) to 45 V DC
• Ex ia: 12 (13) to 30 V DC
Output 4 to 20 mA with superimposed HART protocol
Options • NACE-compliant materials
• Software pre-configurations
1) MWP: depends on the lowest-rated element, with regard to pressure, of the selected component
Product design
Level measurement (level, volume and mass) with Deltabar:

Deltabar FMD71, FMD72
Endress+Hauser 9
2
13
A0016449
1 Sensor module LP
2 Sensor module HP
3 Transmitter
The FMD71/FMD72 is best suited to level measurement in tanks with pressure overlay or vacuum
vessels and tanks, high distillation columns and other vessels with changing ambient temperatures.
The sensor module HP is mounted on the lower measuring connection and the sensor module LP is
mounted above the maximum level. The transmitter can be mounted on pipes or walls with the
mounting bracket.
The sensor signal is transmitted digitally. In addition, sensor temperatures and the individual process
pressures present at the respective sensor modules can be individually evaluated and transmitted.
System integration The device can be given a tag name (max. 32 alphanumeric characters).
Designation Version 1)
Measuring point (TAG), see additional specifications Z1
1) Product Configurator, "Identification" section

Deltabar FMD71, FMD72
10 Endress+Hauser
Input
Measured variable Measured process variables
• Pressure HP and Pressure LP
• Sensor temperature
Calculated process variables
• Differential pressure
• Level (level, volume or mass)
FMD71: measuring range of
individual sensors
The URL of the differential pressure corresponds to the nominal value of the HP sensor.
Relative pressure
Nominal value Range limit MWP OPL Vacuum resistance 1) Version 2)
lower (LRL) upper (URL)
[bar (psi)] [bar (psi)] [bar (psi)] [bar (psi)] [barabs (psiabs)]
100 mbar (1.5 psi) –0.1 (–1.5) +0.1 (+1.5) 2.7 (40.5) 4 (60) 0.7 (10.5) 1C
250 mbar (4 psi) –0.25 (–4) +0.25 (+4) 3.3 (49.5) 5 (75) 0.5 (7.5) 1E
400 mbar (6 psi) –0.4 (–6) +0.4 (+6) 5.3 (79.5) 8 (120) 0 1F
1 bar (15 psi) –1 (–15) +1 (+15) 6.7 (100.5) 10 (150) 1H
2 bar (30 psi) –1 (–15) +2 ([phone] (270) 1K
4 bar (60 psi) –1 (–15) +4 (+60) 16.7 (250.5) 25 (375) 1M
10 bar (150 psi) –1 (–15) +10 (+150) 26.7 (400.5) 40 (600) 1P
40 bar (600 psi) –1 (–15) +40 (+600) 40 (600) 60 (900) 1S
1) The vacuum resistance applies for the measuring cell under reference operating conditions. (see "Reference operating conditions" section)
2) Product Configurator, "Sensor range" section
Absolute pressure
Nominal value Range limit MWP OPL Vacuum resistance 1) Version 2)
lower (LRL) upper (URL)
[barabs (psiabs)] [barabs (psiabs)] [barabs (psiabs)] [barabs (psiabs)] [barabs (psiabs)]
100 mbar (1.5 psi) 0 +0.1 (+1.5) 2.7 (40.5) 4 (60) 0 2C
250 mbar (4 psi) 0 +0.25 (+4) 3.3 (49.5) 5 (75) 2E
400 mbar (6 psi) 0 +0.4 (+6) 5.3 (79.5) 8 (120) 2F
1 bar (15 psi) 0 +1 (+15) 6.7 (100.5) 10 (150) 2H
2 bar (30 psi) 0 +2 ([phone] (270) 2K
4 bar (60 psi) 0 +4 (+60) 16.7 (250.5) 25 (375) 2M
10 bar (150 psi) 0 +10 (+150) 26.7 (400.5) 40 (600) 2P
40 bar (600 psi) 0 +40 (+600) 40 (600) 60 (900) 2S
1) The vacuum resistance applies for the measuring cell under reference operating conditions. (see "Reference operating conditions" section)
2) Product Configurator, "Sensor range" section

Deltabar FMD71, FMD72
Endress+Hauser 11
FMD72: measuring range of
individual sensors
The URL of the differential pressure corresponds to the nominal value of the HP sensor.
Relative pressure
Nominal value Range limit MWP OPL Vacuum resistance 1) Version 2)
lower (LRL) upper (URL) Silicone oil
[bar (psi)] [bar (psi)] [bar (psi)] [bar (psi)] [barabs (psiabs)]
400 mbar (6 psi) –0.4 (–6) +0.4 (+6) 4 (60) 6 (90) 0.01 (0.15) 1F
1 bar (15 psi) –1 (–15) +1 (+15) 6.7 (100) 10 (150) 1H
2 bar (30 psi) –1 (–15) +2 (+30) 13.3 (200) 20 (300) 1K
4 bar (60 psi) –1 (–15) +4 (+60) 18.7 (280.5) 28 (420) 1M
10 bar (150 psi) –1 (–15) +10 (+150) 26.7 (400.5) 40 (600) 1P
40 bar (600 psi) –1 (–15) +40 (+600) 100 (1500) 160 (2400) 1S
1) The vacuum resistance applies for the measuring cell under reference operating conditions. (see "Reference operating conditions" section)
2) Product Configurator, "Sensor range" section
Absolute pressure
Nominal value Range limit MWP OPL Vacuum resistance 1) Version 2)
lower (LRL) upper (URL) Silicone oil
[barabs (psiabs)] [barabs (psiabs)] [barabs (psiabs)] [barabs (psiabs)] [barabs (psiabs)]
1 bar (15 psi) 0 +1 (+15) 6.7 (100) 10 (150) 0.01 (0.15) 2H
2 bar (30 psi) 0 +2 (+30) 13.3 (200) 20 (300) 2K
4 bar (60 psi) 0 +4 (+60) 18.7 (280.5) 28 (420) 2M
10 bar (150 psi) 0 +10 (+150) 26.7 (400.5) 40 (600) 2P
40 bar (600 psi) –1 (–15) +40 (+600) 100 (1500) 160 (2400) 2S
1) The vacuum resistance applies for the measuring cell under reference operating conditions. (see "Reference operating conditions" section)
2) Product Configurator, "Sensor range" section

Deltabar FMD71, FMD72
12 Endress+Hauser
Output
Output signal 4 to 20 mA with superimposed digital communication protocol HART 6.0, 2-wire
Operation
External (A) 1) + LCD (C) Internal (B) + LCD (C) Internal (B)
on
off
damp.
Display
Sensor
HART
R
FIELDCOMMUN ICATION PROTOCO L
SW /min
E
+
–
A B C
A0021280
Order code version 2)
5 4 8
1) In the case of the T17 transmitter housing, the operating keys are always arranged internally on the
electronic insert.
2) Product Configurator, "Display, operation:" section
Signal range – 4 to
20 mA HART
3.8 mA to 20.5 mA
Signal on alarm According to NAMUR NE43
• Max. alarm: (factory setting: 22 mA) can be set from 21 to 23 mA
• Hold measured value: last measured value is held
• Min. alarm: 3.6 mA
Maximum load In order to guarantee sufficient terminal voltage in two-wire devices, a maximum load resistance R
(including line resistance) must not be exceeded depending on the supply voltage U0 of the supply
unit.
In the following load diagrams, observe the position of the jumper and the explosion protection:
U – 12 V U – 13 V
RLmax 23 mA 23 mA
£
30
20
12 U
[V]
40 45
1217
1435
783
348
[ ]W[ ]W
RLmax RLmax
30
20
13 40 45
1174
1391
739
304
Test
Test
£
3
A B
1
3
2
1
2
RLmax
U
[V]
A0017533
A Jumper for 4 to 20 mA test signal set to "Non-test" position
B Jumper for 4 to 20 mA test signal set to "Test" position
1 Power supply for II 1/2 G Ex ia, FM IS, CSA IS
2 Power supply for devices for the non-hazardous area, 2 G Ex d, 3 G Ex nA, FM XP, FM NI, CSA XP, CSA dust
ignition-proof
3 RLmax maximum load resistance
U Supply voltage

Deltabar FMD71, FMD72
Endress+Hauser 13
Dead time, time constant Presentation of the dead time and the time constant:
I
63 %
100 %
t
t1t2
90 %
t3
A0019786
Dynamic behavior,
current output Dead time (t1) [ms] Time constant (T63), t2Time constant (T90), t3
max. 120 120 280
Dynamic behavior, HART Dead time (t1) [ms] Dead time (t1) [ms] +
Time constant T63 (= t2) [ms]
Dead time (t1) [ms] +
Time constant T90 (= t3) [ms]
min. 280 400 560
max. 1100 1220 1380
Reading cycle
• Acyclic: max. 3/s, typically 1/s (depending on command # and number of preambles)
• Cyclic (burst): max. 3/s, typically 2/s
The Deltabar FMD71/FMD72 offers BURST MODE functionality for cyclical value transmission via
the HART communication protocol.
Cycle time (update time)
Cyclic (burst): min. 300 ms.
Response time
• Acyclic: min. 330 ms, typically 590 ms (depending on command # and number of preambles)
• Cyclic (burst): min. 160 ms, typically 350 ms (depending on command # and number of
preambles)
Damping A damping affects all outputs (output signal, display):
• Via onsite display, handheld terminal or PC with operating program, continuous from 0 to 999 s
• Via DIP switch on the electronic insert, switch position "on" = set value and "off"
• Factory setting: 2 s
Damping can be switched on or off using a switch on the electronic insert. If the switch is on, the
time constant can be set via a parameter in the menu and if the switch is off, the output signal is not
damped (time constant = 0.0).
Alarm current Designation Version 1)
Configured min alarm current IA
1) Product Configurator, "Service" section
Firmware Version Designation Version 1)
01.00.zz, HART, DevRev01 78
1) Product Configurator, "Firmware Version" section

Deltabar FMD71, FMD72
14 Endress+Hauser
Protocol-specific data Manufacturer ID 17 (0x11)
Device type ID 39 (0x27)
HART specification 6.0
Device description files (DTM, DD) Information and files under:
•www.endress.com
•www.hartcomm.org
HART device variables Measured values for PV (primary variable)
• Differential pressure
• Level linear (before lin.)
• Level after linearization table
Measured values for SV, TV, QV (second, third and fourth variable)
• Measured differential pressure
• Corrected pressure
• Measured pressure HP
• Sensor press. HP
• Sensor temperature HP
• Measured pressure LP
• Sensor press. LP
• Sensor temperature LP
• Level before linearization
• Tank content
• Electronic temperature
Supported functions • Burst mode
• Additional transmitter status

Deltabar FMD71, FMD72
Endress+Hauser 15
Power supply
NOTICE
Limitation of electrical safety due to incorrect connection!
‣In accordance with IEC/EN61010 a separate circuit breaker must be provided for the device .
‣When using the measuring device in hazardous areas, installation must comply with the
corresponding national standards and regulations and the Safety Instructions or Installation or
Control Drawings.
‣All explosion protection data are given in separate documentation which is available upon
request. The Ex documentation is supplied as standard with all devices approved for use in
explosion hazardous areas.
‣Devices with integrated overvoltage protection must be grounded.
‣Protective circuits against reverse polarity, HF influences and overvoltage peaks are integrated.
Terminal assignment
4... 20mA Test
Test
Test
4... 20mA Test
1
8
6
7
2
3
4
5
A0019989
1 Housing
2 Supply voltage (see the following section on "Supply voltage")
3 4 to 20 mA
4 Devices with integrated overvoltage protection are labeled "OVP" (overvoltage protection) here.
5 External ground terminal
6 4 to 20 mA test signal between positive and test terminal
7 Internal ground terminal
8 Jumper for 4 to 20 mA test signal
Supply voltage Electronic version Jumper for 4 to 20 mA test signal in
"Test" position (delivery status)
Jumper for 4 to 20 mA test signal
in "Non-test" position
4 to 20 mA HART, version for
non-hazardous areas
13 to 45 V DC 12 to 45 V DC
Measuring a 4 to 20 mA test signal
A 4 to 20 mA test signal may be measured via the positive and test terminal without interrupting
the measurement. The minimum supply voltage of the device can be reduced by simply changing the
position of the jumper. As a result, operation is also possible with a lower supply voltage. To keep the
corresponding measured error below 0.1 %, the current measuring device should exhibit an internal
resistance of <0.7Ω. Observe the position of the jumper in accordance with the following table.

Deltabar FMD71, FMD72
16 Endress+Hauser
Jumper position for test
signal
Description
Test
A0019992
• Measurement of 4 to 20 mA test signal via the positive and test terminal:
possible. (Thus, the output current can be measured without interruption via
the diode.)
• Delivery status
• Minimum supply voltage: 13 V DC
Test
A0019993
• Measurement of 4 to 20 mA test signal via positive and test terminal: not
possible.
• Minimum supply voltage: 12 V DC
Cable specification for
transmitter connection
• Endress+Hauser recommends using twisted, shielded two-wire cables.
• Terminals for core cross-sections0.5 to 2.5 mm2 (20 to 14 AWG)
• The cable outer diameter depends on the cable entry used.
Cable entries Explosion protection Type Permitted cable diameter Permitted wire cross-sections
• Standard
• Ex ia
Plastic M20x1.5 5 to 10 mm (0.2 to 0.39 in) 0.5 to 2.5 mm2 (20 to 14 AWG)
• Ex nA
• FM approval
• CSA approval
Metal M20 x 1.5 7 to 10.5 mm (0.28 to 0.41 in)
Residual ripple Without influence on 4 to 20 mA signal up to ±5 % residual ripple within the permitted voltage
range [according to HART hardware specification HCF_SPEC-54 (DIN IEC 60381-1)]
Influence of power supply ≤0.0006 % of URL/1 V
Overvoltage protection Standard version
The standard version of the pressure instruments does not contain any special elements to protect
against overvoltage ("wire to ground"). Nevertheless the requirements of the applicable EMC
standard EN 61000-4-5 (testing voltage 1kV EMC wire/ground) are met.
Optional overvoltage protection
Devices showing version "NA" in feature 610 "Accessory Mounted" in the order code are equipped
with overvoltage protection.
• Overvoltage protection:
– Nominal functioning DC voltage: 600 V
– Nominal discharge current: 10 kA
• Surge current check î = 20 kA satisfied as per DIN EN 60079-14: 8/20 μs
• Arrester AC current check I = 10 A satisfied
NOTICE
Device could be destroyed!
‣Devices with integrated overvoltage protection must be grounded.

Deltabar FMD71, FMD72
Endress+Hauser 17
Performance characteristics - general
Reference operating
conditions
• As per IEC 60770
• Ambient temperature TA = constant, in the range of:+21 to +33 °C (+70 to +91 °F)
•Humidityj= constant, in the range of: 5 to 80 % rH
• Ambient pressure pA = constant, in the range of:860 to 1 060 mbar (12.47 to 15.37 psi)
• Position of the measuring cell = constant, in range: horizontal ±1° (see also "Influence of the
installation position" section (→  17))
• Input of Lo Trim Sensor and Hi Trim Sensor for lower range value and upper range value
• Zero based span
• Material of process isolating diaphragm FMD71: Al2O3 (aluminum oxide ceramic, Ceraphire®)
• Material of process isolating diaphragm FMD72: AISI 316L (1.4435)
• Filling oil: silicone oil
• Supply voltage: 24 V DC ±3 V DC
• Load with HART: 250 Ω
Measuring uncertainty for
small absolute pressure
measuring ranges
The smallest extended uncertainty of measurement that can delivered by our standards is:
• in range 1 to 30 mbar (0.0145 to 0.435 psi): 0.4 % of reading
• in range < 1 mbar (0.0145 psi): 1 % of reading.
Resolution • Current output: 1 μA
• Display: can be set (factory setting: presentation of the maximum accuracy of the transmitter)
Influence of the installation
position
90°
90°
C
A
B
A0016465
Process isolating diaphragm axis
is horizontal (A)
Process isolating diaphragm pointing
upwards (B)
Process isolating diaphragm pointing
downwards (C)
FMD71 Calibration position, no
measurement error
< +0.2 mbar (+0.003 psi) < –0.2 mbar (–0.003 psi)
FMD72 sensor with
1/2" thread and silicone
oil
< +4 mbar (+0.06 psi) < –4 mbar (–0.06 psi)
FMD72 sensor with
thread > 1/2" and
flanges
< +10 mbar (+0.145 psi)
The value is doubled for inert oil.
< –10 mbar (–0.145 psi)
The value is doubled for inert oil.
If the sensors are mounted at 180° to one another, this doubles the effect of the deviation which
influences the differential pressure or the level signal.
This effect can be corrected using the function to adjust the position (position adjustment) for the
differential pressure. Additional position adjustments for individual pressure signals are not
available.
A position-dependent zero shift can be corrected on the device .
Warm-up period 4 to 20 mA HART : < 10 s

Deltabar FMD71, FMD72
18 Endress+Hauser
Vibration effects Test standard Vibration effects
IEC 61298-3 ≤ Reference accuracy up to 10 to 60 Hz: ±0.35 mm (±0.01 in); 60 to 500 Hz: 2 g
Application limits A high ratio between the level and head pressure can result in large measured errors. A maximum
ratio of 1:10 is recommended. For calculation purposes, please use the free "Applicator" calculation
tool, which is available online at "www.endress.com/applicator" or on CD-ROM.

Deltabar FMD71, FMD72
Endress+Hauser 19
Performance characteristics - devices with ceramic
process isolating diaphragm
FMD71 reference accuracy The reference accuracy contains the non-linearity [DIN EN 61298-2 3.11] including the pressure
hysteresis [DIN EN 61298-23.13] and non-repeatability [DIN EN 61298-2 3.11] in accordance with
the limit point method as per [DIN EN 60770].
The specifications refer to the calibrated span.
Measuring cell Sensor Reference accuracy (A)
[%URL for every sensor]
Calculated reference accuracy (ADiff)
of the differential pressure
Standard Platinum
100 mbar (1.5 psi) Relative pressure A = ±0.075 - Calculation (mbar, bar or psi):
ADiff HP HP
2
(A URL ) += .LP LP
2
(A URL )
.
100 100
A0016468
Percentage calculation of URL dP:
A [%] P
100
.
Diff
Diff
=ADiff
A0016469
250 mbar (3.75 psi) Relative pressure A = ±0.075 -
400 mbar (6 psi) Relative pressure A = ±0.075 -
1 bar (15 psi)
2 bar (30 psi)
4 bar (60 psi)
10 bar (150 psi)
40 bar (600 psi)
Relative pressure/ Absolute pressure A = ±0.075 A = ±0.05
Ordering information
Designation Version 1)
Platinum D
Standard G
1) Product Configurator, "Reference accuracy" section

Deltabar FMD71, FMD72
20 Endress+Hauser
Thermal change of the zero
output and the output span
for FMD71
Standard version
Measuring cell –10 to +60 °C (+14 to +140 °F) –20 to –10 °C (–4 to +14 °F)
+60 to +125 °C (+140 to +257 °F)
Calculated thermal change (TDiff)
of the differential pressure
% of the set span for every sensor
100 mbar (1.5 psi)
250 mbar (4 psi)
400 mbar (6 psi)
Ttotal = ±0.176 Ttotal = ±0.276 Calculation (mbar, bar or psi):
TDiff HP HP
2
(T URL ) += .LP LP
2
(T URL )
.
100 100
A0016474
Percentage calculation of URL dP:
T [%] P
100
.
Diff Diff
=TDiff
A0016475
1 bar (15 psi)
2 bar (30 psi)
4 bar (60 psi)
10 bar (150 psi)
40 bar (600 psi)
Ttotal = ±0.092 Ttotal = ±0.250
High-temperature version
Measuring cell Sensor –10 to +60 °C
(+14 to +140 °F)
+60 to +150 °C
(140 to +302 °F)
Calculated thermal change (TDiff)
of the differential pressure
% of the set span for every sensor
100 mbar (1.5 psi)
250 mbar (4 psi)
400 mbar (6 psi)
Relative
pressure
Ttotal = ±0.176 T = ±0.75 Calculation (mbar, bar or psi):
TDiff HP HP
2
(T URL ) += .LP LP
2
(T URL )
.
100 100
A0016474
Percentage calculation of URL dP:
T [%] P
100
.
Diff Diff
=TDiff
A0016475
1 bar (15 psi)
2 bar (30 psi)
4 bar (60 psi)
10 bar (150 psi)
40 bar (600 psi)
Relative
pressure
Ttotal = ±0.092 T = ±0.5
1 bar (15 psi)
2 bar (30 psi)
4 bar (60 psi)
10 bar (150 psi)
Absolute
pressure
Ttotal = ±0.092 T = ±0.75
40 bar (600 psi) Absolute
pressure
Ttotal = ±0.092 T = ±0.5