Free notes
Insulation resistance: what good and bad look likeThe lamp lit up. What does that tell you?
Free from the notes: Sparky’s video on it, the section word for word as members see it, and a PDF to keep.
The notes
Exactly as they are on the site.
Picked up at Guidance Note 3 · p.70. The minimum in the table is 1 MΩ, but in new installations a value below 20 MΩ should be investigated.
Example: a load left connected
Lighting circuit, lamp still in, tested line to neutral Reading = 0.160 MΩ And = the lamp lit up during the test
That is the signature of a load left in circuit. The reading is nonsense and the lamp lighting tells you why.
| Equipment | What to do before testing |
|---|---|
| Dimmer switch | Drop the plate and bypass the cables behind it with connector blocks |
| Cooker outlet or FCU with a neon | Drop the plate and bypass |
| SPD | Pull it out of the system — it unplugs |
| AFDD | Remove or isolate it |
Free section from Sparky Study Notes. The full Level 3 notes, 1,463 practice questions and the video lessons: sparkystudynotes.co.uk
Test yourself on it
The tests are in the members’ area. Get one wrong and it shows you why, and where to revise.
Get new notes and exam tips from Sparky
About one email a fortnight. Unsubscribe any time. Privacy noticeThat was one section. There are 583.
Sparky Study Notes is the whole Level 3 syllabus written up like this: the explanation, the worked example, and where it is in your book. With a video lesson for every part and a practice paper for every exam.
- 583sections of written notes
- 35video lessons
- 1,463practice questions
- 146diagrams, redrawn
- 18th Edition
- Building Regs
- PAT
- Fundamental Inspection & Testing
- Initial Verification
- Periodic Inspection & Testing