Search

Premium Membership ♕

Save 50% on all EEP Academy courses with Enterprise Membership Plan and study specialized LV/MV/HV technical articles & guides.

Home / Download Center / Electrical Engineering Books and Technical Guides / Electrical engineering guides / Testing and commissioning of electrical installations for students

Continuity of ring final circuit conductors

A test is required to verify the continuity of each conductor including the circuit protective conductor (cpc) of every ring final circuit. The test results should establish that the ring is complete and has no interconnections.

Testing and commissioning of electrical installations for students
Testing and commissioning of electrical installations for students

The test will also establish that the ring is not broken. Figure 1 shows a ring circuit illustrating these faults.

It may be possible, as an alternative and in order to establish that no interconnected multiple loops have been made in the ring circuit, for the inspector to check visually each conductor throughout its entire length.

Test of continuity of ring final circuit conductors
Figure 1 – Test of continuity of ring final circuit conductors

However, in most circumstances this will not be practicable and the following test method for checking ring circuit continuity is recommended.

The line, neutral and protective conductors are identified and their resistances are measured separately (see Figure 2). The end-to-end resistance of the protective conductor is divided by four to give R2 and is recorded on the installation schedule form.

A finite reading confirms that there is no open circuit on the ring conductors under test.

Measurement of phase, neutral and protective conductors
Figure 2 – Measurement of phase, neutral and protective conductors

The resistance values obtained should be the same (within 0.05 ohms) if the conductors are the same size. If the protective conductor has a reduced csa, the resistance of the protective loop will be proportionally higher than that of the line or neutral loop.

If these relationships are not achieved then either the conductors are incorrectly identified or there is a loose connection at one of the accessories!

Title:Testing and commissioning of electrical installations for students  – Pearson Schools
Format:PDF
Size:2.1 MB
Pages:36
Download:Right here | Video Courses | Membership | Download Updates
Testing and commissioning of electrical installations for students
Testing and commissioning of electrical installations for students

Premium Membership

Get access to premium HV/MV/LV technical articles, advanced electrical engineering guides, papers, and much more! It will help you to shape up your technical skills in your everyday life as an electrical engineer.
50% Discount 💥 - Save 50% on all 90+ video courses with Enterprise Membership plan.

More Information

Leave a Comment

Tell us what you're thinking. We care about your opinion! Please keep in mind that comments are moderated and rel="nofollow" is in use. So, please do not use a spammy keyword or a domain as your name, or it will be deleted. Let's have a professional and meaningful conversation instead. Thanks for dropping by!

5  ×  nine  =  

Learn How to Design Power Systems

Learn to design LV/MV/HV power systems through professional video courses. Lifetime access. Enjoy learning!

Subscribe to Weekly Newsletter

Subscribe to our Weekly Digest newsletter and receive free updates on new technical articles, video courses and guides (PDF).
EEP Academy Hand-Crafted Courses
MV Switchgear Components