Engineering tools
Electrical engineering tools
Calculators for cable sizing, voltage drop and everyday low-voltage installation questions, with the formulas and limits behind them.
Low-voltage installation tools for engineers, electricians and technically minded owners. Results are computed from the stated formula and assumptions; always confirm against the standard that applies to your installation.
Reading the results
Voltage drop limits differ by standard and by load type. Lighting circuits are commonly held to a tighter limit than power circuits, and a long feeder plus a long final circuit must be assessed together. The tools state which limit they compare against; the linked guides explain where those limits come from.