Conduit Fill
IET on-site guide factor method
Reading 4
m
Reading 5 m
Results
Fill
26%
OK
✓
Total cable factor120 (4 × 30)
Conduit capacity460 (20mm straight)
Headroom340
What to buy — 4 items
20mm PVC conduit (3m length)
2 pc
20mm conduit coupling
1 pc
20mm conduit saddle
500mm centres
10 pc
20mm 90° bend / inspection elbow
2 pc
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