Phase Sequence Testing
Regulation 612.12 of BS 7671 requires the checking of phase sequence in multi-phase installations, in order to ensure that the phase sequence is maintained throughout the whole of the installation.
On the City and Guilds 2391 practical assessments, the phase sequence on the 3 phase installation would affect the rotation of the motor on the motor supply circuit (motor not present on the exam).
You will be required to select the appropriate Phase Sequence tester and perform a test at the Main Switch and at the motor connections.
Both tests should indicate the same phase sequence.
Next we move on to RCD testing.
Important things to remember:
This is a live test so extra care is advised!
During the testing remember to constantly inspect the installation for faults and signs of damages.
C&G 2391 - Guide to Inspection and Testing
Initial Verification- Periodic Inspection and Testing
- Qualifications needed for inspection and testing
- The inspection and testing exams
- The C&G 2391 online and written exams
- The C&G 2391 practical exam - Initial Verification
- The C&G 2391 practical exam - Periodic Inspection
- Testing procedures:
- Continuity testing
- Ring circuit testing
- Insulation resistance testing
- Polarity testing
- Earth Fault Loop Impedance tests
- Prospective Fault Current test (PFC test)
- Phase sequence test
- RCD test
- Functional testing
- Certification
- Exam practice:
- C&G 2391 Unit 301 Sample Test No1
- C&G 2391 Unit 301 Sample Test No2
- C&G 2391 Unit 301 Sample Test No3
- C&G 2391 MOCK exam paper ONE with answers
- C&G 2391 EXAM QUESTIONS with answers
- Old exam papers:
- C&G 2394 - 2395 big collection of past exam papers
- See also:
- Periodic Inspection and Testing
- Fault finding with IR test
