Issue:
legacy MA Characteristics
Product Line:
I-Line Panelboards
Environment:
UL 67, UL 50, CSA C22.2 No.'s 29 & 94-1989, NEMA PB1, NFPA 70 Art. 408, Federal Specification W-P-115C Type 1 Class 1 , 2000 IBC, 1995 NBCC
Cause:
The legacy MA (and related higher AIR frames such as MH, MX, ME) were available in higher ampere ratings; however, these higher ampere ratings were never available with an I-Line jaw for installation in an I-Line panelboard or the I-Line distribution section of a Power-Style or QED2 switchboard.
Resolution:
800A was the maximum ampere rating for an MA frame I-Line branch breaker. This required an HCWM interior. For 900A or 1000A ratings, the legacy NA frame had to be used. The ``N`` frame breaker required an HCWM-U interior (now obsolete) or an HCR-U interior. Both the MA frame and NA frame circuit breakers are now obsolete. The MA frame is superseded by either the Powerpact M or Powerpact P circuit breaker, according to application details. The NA frame circuit breaker is superseded by either the Powerpact P or Powerpact R circuit breaker according to application details.
legacy MA Characteristics
Product Line:
I-Line Panelboards
Environment:
UL 67, UL 50, CSA C22.2 No.'s 29 & 94-1989, NEMA PB1, NFPA 70 Art. 408, Federal Specification W-P-115C Type 1 Class 1 , 2000 IBC, 1995 NBCC
Cause:
The legacy MA (and related higher AIR frames such as MH, MX, ME) were available in higher ampere ratings; however, these higher ampere ratings were never available with an I-Line jaw for installation in an I-Line panelboard or the I-Line distribution section of a Power-Style or QED2 switchboard.
Resolution:
800A was the maximum ampere rating for an MA frame I-Line branch breaker. This required an HCWM interior. For 900A or 1000A ratings, the legacy NA frame had to be used. The ``N`` frame breaker required an HCWM-U interior (now obsolete) or an HCR-U interior. Both the MA frame and NA frame circuit breakers are now obsolete. The MA frame is superseded by either the Powerpact M or Powerpact P circuit breaker, according to application details. The NA frame circuit breaker is superseded by either the Powerpact P or Powerpact R circuit breaker according to application details.