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Cable Grouping Factor (Cg) Calculator
Grouping correction factor (Cg) from BS 7671 Table 4C1 for circuits run together, with a derating example.
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Browse the full shop →Frequently asked questions
How do I use the cable grouping factor (cg) calculator?
Enter your measurements and options into the Cable Grouping Factor (Cg) above and the result updates instantly. Grouping correction factor (Cg) from BS 7671 Table 4C1 for circuits run together, with a derating example.
Is the cable grouping factor (cg) calculator free to use?
Yes — every TradesMate calculator is free to use with no sign-up. Save quotes and use the full estimator with a free trial.
Are the results accurate enough to quote from?
The figures are reliable estimates based on standard UK trade practice. Always allow for wastage and verify against current material prices before quoting a customer.
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