Digital protection relay test procedure elaboration
ONEE-BE internship focused on formalizing repeatable test procedures for Siemens SIPROTEC digital protection relays using the OMICRON CMC test set and Test Universe software.
Company: ONEE-BE (Mohammedia Thermal Power Plant) | Duration: July 2024 - August 2024
Relay family
SIPROTEC
Siemens digital protection relay study.
Test platform
OMICRON CMC
Fault simulation and response measurement.
Protection scope
87G / 51G / 64G
Generator and transformer protection functions.
Evaluation
18.5/20
Supervisor grade for the internship work.
Internship scope
Industrial context
The relay tests concerned protection equipment installed on the alternator and transformers of the Mohammedia Thermal Power Plant, where repeatable verification is essential for safe operation.
Mission objective
The goal was to write a structured procedure that links protection theory, OMICRON CMC injection tests, SIPROTEC response checks, and documentation usable by maintenance teams.
Technical work
Relay configuration analysis
Studied Siemens SIPROTEC 7UT6x family relays and key protective functions such as differential protection 87G, overcurrent 51G, and stator earth fault 64G.
Test protocol development
Created step-by-step procedures to verify trip settings, pickup behavior, response timing, and protective logic using Quick CMC, Ramping, and State Sequencer.
Hands-on testing
Applied the procedures with OMICRON Test Universe to simulate fault conditions and observe relay behavior under controlled secondary injection tests.
Critical equipment verification
Focused on generator and step-up transformer protection chains, from CT/VT secondary terminals through relay logic and trip outputs.
Results and takeaways
Achieved outcomes
The project delivered a documented protection relay test procedure and connected classroom protection concepts with high-voltage maintenance practice.
- Built repeatable verification steps for SIPROTEC relay functions and trip behavior.
- Practiced OMICRON Test Universe modules including Quick CMC, Ramping, and State Sequencer.
- Understood how protection relays contribute to the safety and reliability of a major thermal power plant.
Documentation & gallery
On-site work and test equipment
The visual record shows hands-on relay panel work and OMICRON CMC setup used for protection relay testing in the electrical workshop.
Supervisor evaluation (18.5/20)
Overall remarks
"Good asset."
(Original: "Bon élément")
The overall grade awarded was 18.5/20.
