BKH-b Miniature Circuit Breaker: Comprehensive Guide for PLC Industrial Automation Systems

8. januar 2026

Historical parts record: Photos and notes below belong to this record. Confirm the offered unit’s full model, condition and available test evidence before ordering.

What is the LS BKH-b D100A 3P?

The BKH-b D100A 3P is LS Electric's high-current miniature circuit breaker: a DIN-rail breaker rated 100 A on a D trip curve, three-pole, 400 V AC 50 Hz, with the magnetic trip set at 12 times rated current and compliance to GB/T 14048.2 with CCC and CE marks. The factory carton reads 小型断路器 BKH-b, D100A 3P, 4 pcs — four units, new in the LS box, distributed by LS Electric (Wuxi) in China. Each carries the orange triple toggle with its clear anti-tie guard, terminal shields top and bottom, and the LS Korea moulding mark. All 11 photos and 1 video below show these exact units.

3 min readContent reviewed 7 October 2026

Part details

BKH-b 100, as printed on the breaker and carton
Field	Value
Model	LS BKH-b 100, D100A 3P (small-type breaker, 小型断路器)
Rated current	In = 100 A
Trip curve	D — magnetic setting Ii = 12 × In
Rated voltage	400 V AC, 50 Hz
Config	3-pole (1L1/3L2/5L3 to 2T1/4T2/6T3)
Standard / marks	GB/T 14048.2, CCC, CE, Category A
Operating handle	Triple orange toggle with clear interlock guard
Protection	Moulded terminal shields top and bottom
Chassis mark	LS "A KOREA" moulding seal
Carton label	BKH-b D100A 3P, 4 pcs, code 06130831W0, LS Electric (Wuxi)
Quantity	4 breakers, new in box
Shipping weight	0.5 kg as recorded

Scroll sideways to see the full table.

Ratings are read from the face label and the carton sticker in the photo set.

What the D curve buys you at 100 A

A breaker this size usually feeds one thing: a large motor, a transformer, or a welding bus. Those loads throw a starting surge many times their running current, and a standard C-curve trip would see that inrush as a fault. The D curve solves it — the magnetic element here is set at 12 × In, so a 1,200 A motor-start peak passes while a genuine short still trips the breaker in milliseconds. That is also why the three toggles move together under one clear guard: all three phases must break together on a three-phase load, and the guard stops one pole being left behind. The BKH-b series is LS Electric's small-type breaker line for exactly this infeed duty, built to GB/T 14048.2 with CCC certification for the Chinese market, and this batch ships as four identical 3-pole 100 A units in the factory carton — useful as a matched set for a distribution board or as spares that drop straight in. KOEED lists this breaker directly: the BKH-b 3P 100A product page carries the same part.