Brochure

PowerPact H-, J-, and L-Frame Circuit Breakers

Circuit Breakers

Section 3—Circuit Breakers

Dual-Break Rotating Contacts

All PowerPact™ H-, J-, and L-frame circuit breakers are equipped with dual-break rotating contacts

that reduce the amount of peak current during a short circuit fault. This reduces the let-through

currents and enhances equipment protection.

Reduced Let-Through Currents

The moving contact has the shape of an elongated “S” and rotates around a

floating axis. The shape of the fixed and moving contacts are such that the

repelling forces appear as soon as the circuit reaches approximately 15 times I

Due to the rotating movement, repulsion is rapid and the device greatly limits

short-circuit currents, whatever the interrupting level of the unit (D, G, J or L). The

fault current is extinguished before it can fully develop. Lower let-through currents

provide less peak energy, reducing the required bus bar bracing, lowering

enclosure pressure, and delivering improved series or combination ratings. See

page 25 for UL Current-Limiting labels.

High Ampere Interrupting Ratings (AIR)

Circuit breakers are available with interrupting ratings up to:

•

200 kA at 240 Vac delta

•

200 kA at 480 Vac delta

•

100 kA at 600 Vac delta.

See Table 2 for additional performance levels.

Internal Operating Mechanism

PowerPact H-, J-, and L-frame circuit breakers have an over-center toggle mechanism providing quick-

make, quick-break operation. The operating mechanism is also trip-free, which allows tripping even

when the circuit breaker handle is held in the “ON” position.

Internal cross-bars provide common opening and closing of all poles with a single operating handle.

All PowerPact circuit breakers have an integral push-to-trip button in the cover to manually trip the

circuit breaker. This should be used as part of a regular preventive maintenance program.

Push-to-Trip