Field tool / conductor metrology
Measure the resistance of a run, get its length back. Temperature corrected, lead-resistance tared, works for copper, tinned copper and aluminium.
1 · Cable
Stranded adds resistance from the lay of the strands.
2 · Measurement
Loop measurement travels out and back, so it covers twice the run.
Short your probes together and read this first.
Cable temperature, not air temperature.
3 · Checks (optional)
Panel or loop spec. Returns the longest run allowed.
Gives the two-wire DC voltage drop.
Derived
| Run length | — |
| Total conductor in circuit | — |
| Resistance used after tare | — |
| Same reading corrected to 20 °C | — |
| Conductor area | — |
| Single conductor, at measured temp | — |
| Loop pair, at measured temp | — |
| Single conductor, at 20 °C | — |
| Longest run within limit | — |
| Voltage drop over the run | — |