SIPART PS2 Initialization: RUN Messages and Checks
Technical Guide / October 2026 / 4 min read
SIPART PS2 initialization adapts the positioner to the actuator. The RUN messages show which part of that process is active; seeing a RUN number alone does not mean the device has failed. First distinguish a progressing sequence from a message that requires corrective action, then identify the positioner’s feedback design before choosing a corrective procedure.
This guide covers the 4–20 mA/HART families listed in Siemens operating instructions A5E00074631-AJ, edition 05/2026: 6DR50, 6DR51, 6DR52 and 6DR53, plus the remote-electronics variant listed in that manual. It is a guide to interpreting the sequence, not a replacement for the instructions for your order code, firmware and installation.
Identify the feedback design first
Siemens’ product page provides an initialization video specifically for current positioners without a transmission switch or friction clutch. Older instructions that ask you to adjust those parts therefore cannot be applied to every PS2. The 2026 manual separates internal non-contacting position detection from the potentiometer, friction-clutch and gearbox design, and separates linear from part-turn actuators. Use the matching section before changing settings. Siemens PS2 overview and initialization resources; 2026 manual, sections 7.8–7.9.
Before starting an initialization
Initialization can move the actuator through its travel. Qualified personnel must first make that movement safe for the process and keep clear of the feedback linkage. Verify the mounting, electrical supply, pneumatic connections and permitted actuator travel. Do not raise supply pressure beyond the actuator’s rating to force an initialization through. Follow the applicable commissioning precautions, including hazardous-area requirements. Siemens compact instructions, commissioning safety and preparation.
What NOINI, RUN1–RUN6 and FINSH mean
- NOINI: the positioner is not initialized.
- RUN1: establishes the direction of action.
- RUN2: checks travel and determines the end positions.
- RUN3: determines travel times; the sequence also provides a leakage-test function.
- RUN4: determines the smallest positioning increments.
- RUN5: optimizes the transient response.
- RUN6: records pressure values on devices with option -Z P02. It is not a stage required on every PS2.
- FINSH: initialization has completed successfully.
The device then still needs the appropriate mode selection and commissioning checks before being returned to service. Siemens sequence, section 7.3; display messages, pages 221–223.
A slow sequence is different from an error
Siemens allows up to 15 minutes for the complete automatic initialization, depending on the actuator. Do not treat a short pause as proof of a fault. Record the complete display, including alternating text, and whether the actuator is moving. RUN/ERROR is not the only indication that needs attention: other messages, such as U-d < during RUN2, also require the matching check in section 11.2. The overall initialization time is not a reason to ignore an error.
When an error appears, use its matching entry in section 11.2. For example, RUN1/ERROR can involve the air supply or restricted movement, whereas RUN2/ERROR can involve travel settings. These are possible causes, not diagnoses from the display alone. Siemens initialization message table.
If an error persists after the applicable corrective checks, keep the device out of operation and do not restart it. Follow the commissioning safety instructions and obtain qualified support.
Do not confuse initialization with a factory reset
Automatic initialization and manual initialization are separate choices. In manual initialization, the end positions are defined manually while the remaining initialization parameters are determined automatically. A factory preset is another function: PRST can remove the existing adjustment. A reset is therefore not a neutral first response to every commissioning difficulty. Preserve the current configuration and identify the applicable procedure before changing it. Siemens explanation of initialization types.
Record evidence before the next attempt
A useful troubleshooting note separates what you observed from what you suspect. Record:
- The full order code, firmware version and actuator type.
- The feedback design and whether any mounting or configuration changed.
- Both display lines, the stage reached and elapsed time.
- Whether movement occurred in each direction and where it stopped.
- The measured supply condition and the checks already completed.
For example, reporting the exact alternating RUN2/ERROR message, elapsed time and observed travel is more useful than assuming the electronics need replacement. Use that record with the matching official manual or qualified technical support; it is not a substitute for a site assessment.
Related PS2 information
For the product family, see the SIPART PS2 product page. For the information needed to identify a configuration or replacement, use the SIPART PS2 configuration guide. Commissioning instructions should always be selected from the official Siemens manual entry to match the installed device.
Official PS2 documentation
Choose the instructions that match your order code, feedback design and actuator.