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© 2005 Schneider Electric All Rights Reserved

09/2005

QOU Miniature Circuit Breakers and Switches

Application Information

UL HACR Type

HACR is an acronym that designates circuit breakers certified to be used on heating, air conditioning,

and refrigeration loads. The 9th edition of UL489 eliminated special testing requirements for HACR

certification, and the 2005 NEC eliminated the requirement for special HACR marking. HACR marking

is no longer necessary for circuit breakers used in these applications in states and localities where the

2005 NEC has been adopted.

QOU circuit breakers will continue to carry the HACR marking to meet the rquirements of previous

NEC Sections 430 and 440 in areas where the 2005 NEC has not yet been adopted. In older versions

of the NEC, Article 430-53(c) required that each circuit breaker must be of the inverse time type, and

be approved for group installation. The 2005 NEC eliminated the group installation clause of this

article.

The following QOU miniature circuit breakers will continue to carry the HACR label:

•

10–100 A, one-pole

•

10–125 A, two-pole

•

10–100 A, three-pole

High Magnetic

QOU-HM circuit breakers are recommended for area lighting (athletic fields, parking lots, outdoor

signs, etc.) when using lamps of inherent high inrush current or individual dimmer applications, or other

applications where high inrush current exceeds standard tripping conditions. These circuit breakers

are available in 15 A and 20 A only.

QOU-HM circuit breakers are manufactured with the magnetic trip point calibrated at a much higher

level than standard QOU circuit breakers. Table 4 lists the magnetic trip levels to which high-magnetic

circuit breakers are calibrated:

Table 4:

QOU-HM Circuit Breaker Magnetic Trip Levels

QOU-HM Circuit

Breakers

Max. Full-Cycle Magnetic Hold Level

15 A

21–35 x In

315–525 A

20 A

16–26 x In

322–537 A