Use the calculator as a pre-check, not a certificate
The output is a planning or review aid. Final values still need competent design, inspection, testing and current BS 7671/manufacturer data.
Electrical calculator · DB schedule / test sheet / circuit schedule / EICR
DB Circuit Schedule & Test Sheet Sanity Checker
Paste circuit and test-sheet notes to flag missing Zs, R1+R2, IR, RCD or breaker details and generate a cleaner copyable schedule.
For tightening up temporary DB schedules, EICR notes and job-file records before handover.
Field notes
Field notes for DB/test sheet checker
Practical checks to run before this calculator result turns into a site decision.
Compare against the actual protective device
Device type, rating, breaking capacity, curve, RCD type and correction factor assumptions can change the conclusion. Do not rely on a generic label.
Write down the assumptions
If the result is used in a job discussion, record Ze/Zs, cable data, correction factors, supply voltage and any reason for accepting, splitting or investigating the circuit.
FAQ
DB/test sheet checker FAQ
Short answers written for UK temporary electrical and HVAC planning work.
What is the DB/test sheet checker used for?
Paste circuit and test-sheet notes to flag missing Zs, R1+R2, IR, RCD or breaker details and generate a cleaner copyable schedule. It is mainly for UK electrical review work, especially where a quick pre-check is needed before selecting equipment or changing a temporary setup.
Can this replace BS 7671 design, inspection or testing?
No. It is a competent-person planning aid only. Final decisions still need current BS 7671 requirements, manufacturer data, inspection, testing, risk assessment and the actual site conditions.
What should I verify before acting on the result?
Check current BS 7671 values, manufacturer device data, measured results, earthing arrangement, correction factors and site installation conditions. If any assumption is uncertain, use the result as a prompt to investigate rather than as permission to energise.
What does an amber or red result usually mean?
It normally means the margin is weak, an assumption is missing, or the load should be split, staged, moved closer to the supply, reduced or reviewed by a competent electrician before use.
Next tools in this workflow
See super flows
Calculator · BS 7671 / voltage drop
HVAC voltage drop envelope
Estimate voltage drop over long leads for heaters, air movers, dehumidifiers and portable AC, with compressor start warnings.
Calculator · PFC / PSCC
PFC / fault current
Estimate PSCC or PEFC from Ze and voltage, compare against device breaking capacity, and draft a quick test-sheet note.
Calculator · max Zs / MCB
Max Zs checker
Check a measured Zs value against an entered device limit, with optional 80% rule headroom and clear pass/check wording.
Calculator · CPC / adiabatic
CPC adiabatic
Use the adiabatic equation shape to compare fault current, disconnection time, k factor and CPC size as a planning aid.