Siemens SITRANS P DS III is a smart pressure transmitter family that has been used in process industries for many years. Through different MLFB configurations, DS III has been applied for gauge, absolute, differential pressure and flow measurement tasks; widely preferred in energy, oil & gas, chemical, petrochemical, water and OEM applications.
The DS III/P410 family variants are now considered legacy/discontinued products. Siemens product records show that some DS III/P410 variants have been replaced by the SITRANS P320/P420 successor family. Therefore, DS III is especially important today for replacement, spare parts and verification of existing configurations in plants.
Key Features:
✔ Gauge, absolute and differential pressure configurations
✔ Variants for differential pressure and flow measurement
✔ 4–20 mA / HART® options
✔ PROFIBUS PA and FOUNDATION™ Fieldbus variants
✔ Functional Safety / SIL support in suitable MLFBs and configurations
✔ Remote Seal and different diaphragm options
✔ ATEX, IECEx and other hazardous area options
✔ Legacy replacement availability in existing plants
✔ Technical comparison possibility for transition to P320/P420
| MLFB Family | Main Measurement Task | Description |
|---|---|---|
| 7MF4033 | Gauge Pressure | HART®, 4–20 mA pressure transmitter variants |
| 7MF4034 | Pressure | PROFIBUS PA variants |
| 7MF4233 | Absolute Pressure | Absolute pressure transmitter variants |
| 7MF4433 | Differential Pressure / Flow | Differential pressure and flow measurement variants |
| 7MF4533 | Differential Pressure / Flow | Variants for high static pressure applications |
| 7MF4633 | Level | Level measurement based on differential pressure principle |
📌 Note: MLFB prefix alone is not a complete product code. Final technical specifications are defined by the characters following the MLFB. Before ordering or replacement, full MLFB and Siemens technical documentation must be checked together.
7MF4033-1DA00-1AB7 → Gauge pressure transmitter; HART®, 4–20 mA, 0.16–16 bar g measuring range, stainless steel diaphragm and G1/2 B process connection.
7MF4433-1EA02-1AA6 → Differential pressure / flow transmitter; HART®, 4–20 mA, 6–600 mbar measuring range and PN 160 static pressure.
📌 Important: 7MF4033 or 7MF4433 prefixes alone are not sufficient for ordering. Correct product selection must be made through the full MLFB.
SITRANS P DS III detects process pressure in the measuring cell and processes it through the electronic circuit to transmit to the process control system.
Communication options depending on application and MLFB:
4–20 mA
HART®
PROFIBUS PA
FOUNDATION™ Fieldbus
Not every communication protocol is available in all DS III variants. Therefore, communication selection must be verified through the full MLFB.
| Parameter | SITRANS P DS III |
|---|---|
| Measurement tasks | Gauge, Absolute, Differential Pressure, Flow, Level* |
| Analog output | 4–20 mA* |
| Communication | HART®, PROFIBUS PA, FOUNDATION™ Fieldbus* |
| Measuring cell | Depends on MLFB |
| Diaphragm material | Depends on configuration |
| Housing | Depends on configuration |
| Process connection | Depends on MLFB |
| Ex options | Depends on configuration; ATEX/IECEx options |
| Functional Safety | SIL according to IEC 61508 in suitable variants |
\* Output, communication and measurement task depend on selected product variant and full MLFB.
⚡ Power Plants → Steam, condensate, feedwater and auxiliary process systems
🛢️ Oil & Gas → Pipelines, process units, tanks and compressor systems
🧪 Chemical & Petrochemical → Reactors, process lines and differential pressure applications
💧 Water & Wastewater → Pump systems, filtration and process pressure applications
🔧 OEM & Skid Systems → Package process equipment and automation systems
✔ Digital communication options
✔ Functional Safety / SIL support in suitable variants
✔ Remote Seal options
✔ Configurations for hazardous area applications
✔ Wide MLFB family for different measurement tasks
✔ Availability for legacy replacement projects
✔ Integration with existing automation infrastructures
📌 For new projects, SITRANS P320/P420 should be considered instead of DS III.
Commissioning of an existing DS III device or after replacement includes:
Mechanical installation check
Verification of process connections
Power supply check
4–20 mA loop test
HART® / digital communication verification
Zero Adjustment / Zero Trim
Sensor Trim
Alarm and diagnostics check
Verification of Ex requirements
Verification of safety function requirements in SIL applications
| Problem | Possible Cause | Solution |
|---|---|---|
| Measurement deviation | Zero adjustment or process conditions | Perform Zero Adjustment and check process connections |
| Unstable signal | Process fluctuations | Check process conditions and connections |
| HART® communication problem | Loop or configuration | Check wiring and communication parameters |
| No output | Power supply / wiring | Check loop supply and connections |
| Diagnostics alarm | Device or process condition | Review device diagnostics information |
Is SITRANS P DS III still a current Siemens product? No. Relevant DS III/P410 variants are considered legacy/discontinued products.
What does 7MF4033 mean? It is one of the MLFB prefixes representing gauge pressure transmitter variants in the SITRANS P DS III family. Communication and other technical specifications depend on the full MLFB.
What does 7MF4433 mean? It represents SITRANS P DS III variants for differential pressure and flow measurement applications.
Can DS III be used in SIL applications? Yes, Functional Safety / SIL applications are possible in suitable MLFBs and configurations. Final suitability must be verified through Siemens safety documentation.
Which Siemens model can replace DS III? SITRANS P320/P420 is considered the successor family for relevant DS III/P410 variants. Replacement selection must be based on the full MLFB of the existing device.
How to determine the correct product code for DS III? Verification must be made through the full MLFB / Article Number and Siemens technical documentation.
Yeşil Grup Enerji, without being an official Siemens distributor, provides independent and multi-brand industrial supply services for SITRANS P DS III including:
Model and MLFB verification
Siemens datasheet and technical documentation check
Legacy replacement analysis
P320/P420 transition evaluation
Cross-reference studies
Spare parts research
Application suitability evaluation
Global sourcing
Fast RFQ management
International project supply
📧 [email protected] 📞 +90 505 696 61 00 🌐 www.yesilgrupenerji.com
Siemens SITRANS P DS III is a transmitter family that has been used in process industries for many years, supporting gauge pressure, absolute pressure, differential pressure, flow and level measurement tasks through different MLFB variants. With HART®, PROFIBUS PA and FOUNDATION™ Fieldbus communication options, it has been integrated into various process automation infrastructures.
However, relevant DS III/P410 variants are now considered legacy/discontinued products. In Siemens’ current portfolio, SITRANS P320/P420 is highlighted as the successor family. Therefore, while new projects should consider P320/P420 models, existing DS III devices require technical comparison through the full MLFB for replacement and spare part needs.
Yeşil Grup Enerji is not an official Siemens distributor. As an independent and multi-brand industrial supplier, it provides project-based support in MLFB verification, legacy replacement, technical documentation check, cross-reference, application evaluation, global sourcing and fast RFQ processes.
Important Note: For SITRANS P DS III, prefixes such as 7MF4033, 7MF4034 or 7MF4433 alone are not sufficient. Final product selection must be verified through the full MLFB, measurement task, measuring range, static pressure, process connection