#panels
6 posts filed under this tag, newest first.
Power factor still poor after fitting capacitors: why
The bank is installed, the contactors click, and the bill has not moved. Six causes, ranked, and the one clamp-meter test that finds most of them.
7 min read
APFC panels: sizing the steps, and avoiding resonance
How an automatic power factor panel decides what to switch, why the smallest step matters more than the total kVAr, and when you must fit detuned reactors.
6 min read
IP ratings for panels: what IP54, IP65 and IP66 survive
What each digit is tested against, why a higher rating derates your busbars, and the condensation problem that ruins sealed outdoor enclosures.
8 min read
MCCB keeps tripping: how to find out why
Time the trip first — it halves the search. Then work through overload, short circuit, earth fault and the causes that are not faults at all.
7 min read
Busbar sizing: current rating, heat and short-circuit forces
Why amps per mm² is not a constant, what paralleling really buys, and the mechanical force a fault puts on the supports — with the arithmetic worked.
8 min read
MCB, MCCB, ACB and RCCB: what each protects, and where
The four devices compared on rating, breaking capacity and adjustability — plus trip curves, Icu versus Ics, and choosing an RCD type for VFD circuits.
7 min read