Electrical Export Guides
Short, practical notes on the decisions that go wrong most often — trip curves, breaking capacity, residual-current types, coil frequency and certificates.
Cable Size Selection: Ampacity, Correction Factors and Ib ≤ In ≤ Iz
Why 4 mm2 is 32 A in one table and 28 A in another: method, loaded conductors, ambient and grouping — plus the Ib/In/Iz rules and…
Read more →Contactor Sizing by Motor kW: The Table and the Three Checks
A 7.5 kW motor is 15.5 A at 400 V and 14 A at 440 V. The kW-to-current table, the three checks that decide the frame,…
Read more →Contactor Coil Voltage Codes: How to Read Them and Order the Right One
Voltage alone is not the order. How coil codes are built, why frequency changes impedance and pull-in, and the four ordering mistakes that fail in the…
Read more →DIN Rail TS35: 7.5 mm vs 15 mm, TS15 and G32
The 35 mm rail is standard; the depth is not. How 7.5 mm and 15 mm differ, where TS15 and G32 still appear, and how to…
Read more →Busbar Current Rating: Why a Copper Bar Has No Single Amp Figure
Ask for the amp rating of 20 x 5 mm copper and the honest answer is a range. The factors that move it, the adiabatic short-circuit…
Read more →Reversing Contactor Interlock: Wiring, Dead Time and Mistakes
Two contactors, one phase swap, and three interlocks that must all exist. How to wire the coil circuit, why the arc needs a dead time, and…
Read more →Enclosure Size: Planning a Board in DIN Modules
A 12-way board does not hold 12 RCBO circuits. How to count modules, add spare capacity and check depth and heat before ordering.
Read more →MCB Derating in High Ambient Temperature
IEC 60898-1 calibrates at 30 C, and a real enclosure runs hotter than the room. How to derate the breaker, the enclosure and the cable together.
Read more →30 mA vs 100 mA RCD: Which Sensitivity, and Where
30 mA is the personnel-protection setting; 100 mA is the discrimination and earth-fault step above it. How to place both, and why two 30 mA devices…
Read more →Voltage Drop Calculation for Long Cable Runs | HAZAM
At 20 A over 30 m, 2.5 mm2 carries the current and still fails on drop. The 4 mm2 answer is a distance decision, not a…
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