Technical Data
CompareContinuous / Liquids
| Measuring Principle | Differential pressure |
| Characteristic / Application | Digital transmitter with metallic measuring diaphragms one side with diaphragm seal Modular transmitter Long term stability Enhanced safety via self diagnostic functions Secondary process barrier |
| Supply / Communication | 4...20 mA HART: 10,5...45V DC Ex ia: 10,5...30V DC PROFIBUS PA / FOUNDATION Fieldbus: 9...32V DC |
| Accuracy | 0,075% + influence of diaphragm seal |
| Long term stability | 0,05% of URL/year |
| Ambient temperature | -50°C...85°C (-58°F...185°F) |
| Process temperature | -40°C...400°C (-40°F...752°F) |
| Process pressure / max. overpressure limit | 160bar (2400 psi) |
| Pressure measuring range | 100mbar...16bar (1.5psi...230 psi) |
| Main wetted parts | Alloy C276 316L Monel Tantalum |
| Process connection | Low pressure side: 1/4-18NPT RC1/4" High pressure side: Flanges (DIN, ASME, JIS) |
| Max. measurement distance | 160m (525ft) H2O |
| Communication | 4...20 mA HART PROFIBUS PA FOUNDATION Fieldbus |
| Certificates / Approvals | ATEX, FM, CSA, CSA C/US, IEC Ex, INMETRO, NEPSI, EAC |
| Safety approvals | SIL |
| Design approvals | EN10204-3.1 NACE MR0175, MR0103 |
| Options | HistoROM/M-Dat 4-line digital display SS- or Aluminiumhousing Separate housing |
| Successor | PMD78B |
| Application limits | Measuring cell: Metal welded |
Pressure
| Measuring Principle | Differential pressure |
| Characteristic | Digital transmitter with metallic measuring diaphragms, one side with diaphragm seal Modular transmitter Long-term stability Secondary process barrier enhanced saftey via self diagnostic functions |
| Supply voltage | 4...20mA HART 10,5...45V DC (Non Ex): Ex ia: 10,5...30V DC PROFIBUS PA: 9...32 V DC (Non Ex) FOUNDATION Fieldbus: 9...32 V DC (Non Ex) |
| Reference Accuracy | 0,075% + influence of diaphragm seal |
| Long term stability | 0.08 % of URL/ year 0.14 % of URL/ 5 years 0.27 % of URL/ 10 years |
| Process temperature | -40°C...400°C (-40°F...752°F) |
| Ambient temperature | -50°C...85°C (-58°F...185°F) |
| Measuring cell | 100 mbar...16 bar (40 inH20...240 psi) |
| Smallest calibratable span | 5 mbar (0.075 psi) |
| Vacuum resistance | 50 mbar (0.73 psi) |
| Max. Turn down | 100:1 |
| Max. overpressure limit | 160 bar (2400 psi) |
| Process connection | Low pressure side: 1/4-18NPT RC1/4" High pressure side: Flanges (DIN, ASME, JIS) |
| Material process membrane | 316L, AlloyC, Tantal, Gold-Rhodium, PTFE |
| Material gasket | None, diaphragm seal welded |
| Fill fluid | Silicone oil, Inert oil, Vegetable oil Low- temperature oil High- temperature oil |
| Material housing | 316L, Die-cast aluminum |
| Communication | 4...20 mA HART PROFIBUS PA FOUNDATION Fieldbus |
| Certificates / Approvals | ATEX, FM, CSA, CSA C/US, IEC Ex, INMETRO, NEPSI, EAC, UK Ex |
| Safety approvals | SIL |
| Design approvals | NACE MR0175 EN10204-3.1 |
| Specialities | Diagnostic functions |
| Successor | PMD78B |
The Deltabar FMD77 differential pressure transmitter uses a metal sensor with a single-flange diaphragm seal or double-flange seal, with a capillary on the low-pressure side. It is mainly used for the continuous level measurement in the process industry. The built-in HistoROM data module facilitates process and device parameter management. It complies with IEC 61508 and meets SIL3 functional safety requirements.
Advantages
Excellent repeatability and long-term stability
High reference accuracy: up to ±0.075%, platinum version: ±0.05%
The new TempC diaphragm minimizes the influence of ambient and process temperature changes
For flow and differential pressure monitoring to SIL3 requirements, compliant with IEC 61508, certified by TÜV SÜD
HistoROM®/M-DAT memory module
Function monitoring of measuring cell and circuitry
Modular continuous measurement of differential pressure, static pressure and pressure (Deltabar S - Deltapilot S, Cerabar S), e.g. replaceable display, universal electronics for pressure and differential pressure measurement
Areas of application
For liquid level, volume or mass measurement
Process connections: thread and flange
Temperature: -70 ... +400°C (-94 ... +752°F)
Measuring range: +100mbar ... +16bar (+1.5 ... +240psi)
Accuracy: ±0.075%
International explosion protection approval, WHG overflow protection, hygienic approval, marine approval, SIL
Spare Parts & Accessories 76
76 spare parts · click to collapse
| Order code | Description | |
|---|---|---|
| 52020440 | mounting kitconsists of: 2x O-ring 45.69x2.62 EPDM retaining ring, plastics Cerabar S PMC71, PMP71/PMP75 Deltabar S PMD70/PMD75,FMD76/FMD77/FMD78 Deltapilot S FMB70 | Details |
| 71020596 | mounting kitconsists of: 2x O-ring 45.62x69x2.62 EPDM 1x profile gasket 51.4x57.2x1.6 VMQ retaining ring, plastics Cerabar S PMC71/PMP71/PMP75 Deltabar S PMD70/PMD75/FMD76/FMD77/FMD78 Deltapilot S FMB70 | Details |
| 52022418 | key housingfor external operation consists of: push buttons, cover + screws | Details |
| 52022419 | key housingfor external operation consists of: push buttons, cover + screws colour: light grey | Details |
| 52024110 | key housingfor external operation consists of: push button, cover + screws colour: dark grey | Details |
| 52020760 | cable glandconsists of: cable gland M20 O-ring 18.72x2.62 VMQ Cerabar S PMC71, PMP71/PMP75 Deltabar S PMD70/PMD75,FMD76/FMD77/FMD78 Deltapilot S FMB70 | Details |
| 52020761 | cable entryconsists of: gasket 18.72x2.51 NBR adapter M20 > G1/2 O-ring 18.77x1.78 NBR Cerabar S PMC71, PMP71/PMP75 Deltabar S PMD70/PMD75,FMD76/FMD77/FMD78 Deltapilot S FMB70 | Details |
| 52020762 | plug connectorHarting plug set Cerabar S PMC71, PMP71/PMP75 Deltabar S PMD70/PMD75,FMD76/FMD77/FMD78 Deltapilot S FMB70 | Details |
| 52020763 | plug connectorCerabar S PMC71, PMP71/PMP75 Deltabar S PMD70/PMD75,FMD76/FMD77/FMD78 Deltapilot S FMB70 | Details |
| 71111056 | Atmospheric compensation filter portConsists of: Vent screw 304. Pressure compensation filter. O-ring EPDM, protection lid. Usage: FMB50, FMB51, FMB52, FMB53, FMD71, FMD72, FMD76, FMD77, FMD78, FMR60B, FMR62B, FMR63B, FMR66B, FMR67B, PMC51, PMC71, PMD70, PMD75, PMP71, PMP75, PMP51, PMP55. | Details |
| 71219639 | Atmospheric compensation filter portConsists of: vent screw 304. Pressure compensation filter. O-ring VMQ, protection lid. Usage: housing T17, FMB70, FMD76/FMD77/FMD78, PMC71, PMD70/PMD75, PMP71/ PMP75. Housing F15 at B1,BB,BD,BF,GA,ID,I1, FMB50/FMB51/FMB52/FMB53, PMC51, PMP51/PMP55. | Details |
| 71206971 | Seal ring assemblyConsists of: 5x O-ring 75.87x2.62 FVMQ. Usage: housing T14, FMD77/FMD78, PMD70/PMD75, PMP71/PMP75. | Details |
| 52020432 | Aluminum cover with gasketMaterial: Aluminium, coated O-ring EPDM, FDA not for EEx d/XP Cerabar S PMC71, PMP71/PMP75 Deltabar S PMD70/PMD75,FMD76/FMD77/FMD78 Deltapilot S FMB70 | Details |
| 52020433 | Aluminum cover with gasketMaterial: Aluminium, coated O-ring EPDM, FDA for EEx d/XP Cerabar S PMC71, PMP71/PMP75 Deltabar S PMD70/PMD75,FMD76/FMD77/FMD78 | Details |
| 52028309 | ***Cover T14 316L, Ex d, sight glass, EPDMMaterial: 316L Sight glass: mineral glass O-ring EPDM, FDA individual tested, EEx d/XP Cerabar S PMC71, PMP71/PMP75 Deltabar S PMD70/PMD75,FMD76/FMD77/FMD78 | Details |
| 52028310 | Stainless Steel CoverMaterial: 316L O-ring EPDM, FDA individual tested, EEx d/XP Cerabar S PMC71, PMP71/PMP75 Deltabar S PMD70/PMD75,FMD76/FMD77/FMD78 | Details |
| 71002774 | Stainless Steel CoverMaterial: 316L flat gasket VMQ, centering ring, screw not for EEx d/XP Cerabar S PMC71, PMP71/PMP75 Deltabar S PMD70/PMD75,FMD76/FMD77/FMD78 Deltapilot S FMB70 | Details |
| 71002810 | cover with viewing windowMaterial: 316L Sight glass: mineral glass flat gasket VMQ, centering ring, screw approval 2,3,4,8,Q,W,7,8 Cerabar S PMC71, PMP71/PMP75 Deltabar S PMD70/PMD75,FMD76/FMD77/FMD78 Deltapilot S FMB70 | Details |
| 71002811 | cover with viewing windowMaterial: 316L Sight glass: Polycarbonat PC flat gasket VMQ, centering ring, screw approval A,F,R,S,U,1,6 Cerabar S PMC71, PMP71/PMP75 Deltabar S PMD70/PMD75,FMD76/FMD77/FMD78 Deltapilot S FMB70 | Details |
| 71206965 | Stainless Steel CoverMaterial: 316L. O-ring FVMQ. Individual tested, EEx d/XP. Usage: FMD76/FMD77/FMD78, PMC71, PMD70/PMD75, PMP71/PMP72/PMP75. | Details |
Configurator / Comparison
Source:Endress+Hauserwebsite public information
Measuring principle video
Click to playManuals & Documents 12
All documents for this model12 documents · click to expand
Deltabar S FMD77, FMD78, PMD75 HART V02.30.zz Operating Instructions Chinese
Deltabar S FMD77/78; PMD75 FOUNDATION Fieldbus (V 04.00.zz) Operating Instructions Chinese
Deltabar S FMD77/78; PMD75 PROFIBUS PA (V 04.01.zz) Operating Instructions Chinese
仪表功能描述 Cerabar S PMC71, PMP71/75 Deltabar S FMD76/77/78, PMD70/75 Deltapilot S FMB70 Chinese
Deltabar S FMD77, FMD78, PMD75 HART V02.30.zz Operating Instructions English
Deltabar S FMD77/78; PMD75 FOUNDATION Fieldbus (V 04.00.zz) Operating Instructions English
Deltabar S FMD77/78; PMD75 PROFIBUS PA (V 04.01.zz) Operating Instructions English
Cerabar S / Deltabar S / Deltapilot S HART V02.30.zz Description of Instrument Functions English
Cerabar S / Deltabar S / Deltapilot S, Description of device functions FOUNDATION Fieldbus V 04.00.zz English
Cerabar S /Deltabar S /Deltapilot S Description of device functions PROFIBUS PA V04.01.zz English
Cerabar S /Deltabar S /Deltapilot S Description of device functions PROFIBUS PA English
TI Deltabar S PMD75, FMD77, FMD78 Chinese
Case Studies
Municipal Wastewater Treatment · Differential Pressure Measurement — Application Case
Project Overview
The site is the inlet, biological and outlet stages of a municipal plant. The customer wanted Differential Pressure Measurement properly configured on the existing plant, with the aim of differential pressure for flow and filter monitoring.
Technical Challenges
What actually causes trouble is high solids and corrosive fractions, with large diurnal flow swings, and effluent parameters drift and probes foul with sludge and biofilm. All of this means the Differential Pressure Measurement configuration has to involve checking static pressure limit, overload margin and impulse lines.
Configuration
Supply and installation were organised through the pressure range: pressure solution matched to process pressure and temperature. On site this meant checking static pressure limit, overload margin and impulse lines, checked line by line against: stable compliance with Grade 1A discharge limits and online data reporting.
Performance
After commissioning the outcome is filters changed on pressure drop, using cartridges to their full life, and the readings are now used for process tuning.
Food & Beverage · Differential Pressure Measurement — Application Case
Site Conditions
This is a Food & Beverage customer whose plant is at dosing, pasteurising, filling and CIP stages. The main task was differential pressure for flow and filter monitoring.
The Problem
The difficulty lies in syrups, dairy and beverages that scale easily, under strict hygienic requirements; at the same time frequent cleaning demands instruments that withstand hot CIP/SIP caustic cycles. Specification therefore means checking static pressure limit, overload margin and impulse lines.
What We Did
We took a pressure range approach — pressure solution matched to process pressure and temperature. Delivery was built around checking static pressure limit, overload margin and impulse lines, with point-by-point checks on: food-safety and hygienic design per 3-A / EHEDG.
Operating Outcome
In service the system performs as intended — filters changed on pressure drop, using cartridges to their full life, with routine maintenance falling noticeably.
Chemical & Pharmaceutical · Differential Pressure Measurement — Application Case
Application Context
reactors, metering vessels and finished-product tanks is a typical Chemical & Pharmaceutical duty. The project started from Differential Pressure Measurement, focusing on differential pressure for flow and filter monitoring.
Process Constraints
corrosion plus Ex protection shortens instrument life and makes downtime costly, and highly corrosive media with solvents and crystallisation, partly in explosive atmospheres only amplify it. The Differential Pressure Measurement specification must therefore cover checking static pressure limit, overload margin and impulse lines.
Delivery Approach
Delivery was handled as the pressure range — pressure solution matched to process pressure and temperature. Execution centred on checking static pressure limit, overload margin and impulse lines, together with Ex certification and GMP traceability of records.
Field Results
Operation shows the benefit clearly — filters changed on pressure drop, using cartridges to their full life, with confidence in this measuring point improving markedly.
Power & Energy · Differential Pressure Measurement — Application Case
Customer Profile
The typical setting in Power & Energy is boiler feedwater, turbine condensate and FGD/DeNOx systems. The measuring point is Differential Pressure Measurement; the focus is differential pressure for flow and filter monitoring.
Key Difficulties
Conditions are high temperature and pressure with both steam and saline water and, on top of that, drift under high temperature and pressure, with very costly unplanned outages, which a standard configuration cannot handle for long. The design therefore starts with checking static pressure limit, overload margin and impulse lines.
Implementation
The scope ran through the pressure range: pressure solution matched to process pressure and temperature. Technically it hinges on checking static pressure limit, overload margin and impulse lines, and on these requirements: compliance with power-industry codes and unit availability targets.
Customer Benefit
In practice this means filters changed on pressure drop, using cartridges to their full life, which cut the workload on the site maintenance team.
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