Selecting Masterpact MTZ1 Circuit Breakers

NOTE: Throughout this catalog, UL489 means UL489/CSA C22.2 No 5 and ANSI C37 means ANSI C37/CSA C22.2 No 268.

Ratings for UL489 Masterpact MTZ1 Circuit Breakers
Frame Rating		800 A					1200 A					1600 A*
Interrupting Rating Code		N	H	L1	L	LF	N	H	L1	L	LF	N	H	L1	L
Number of poles		3/4
Interrupting Current (kAIR)	240 Vac, 60 Hz	50	65	100	200	200	50	65	100	200	200	50	65	100	200
	480 Vac, 60 Hz	50	50	65	100	100	50	50	65	100	100	50	50	65	100
	600 Vac, 60 Hz	35	50	—	—	—	35	50	—	—	—	35	50	—	—
Short-Time Withstand Current Rating (kA)	Vac 60 Hz, 0.5 s	35	35	10	10	10	35	35	10	10	10	35	35	10	10
Built-In Instantaneous Override (Peak kA ±10%)		90	90	22	22	22	90	90	22	22	22	90	90	22	22
Close and Latch Ratings (Peak kA)	Vac 60 Hz	55	55	22	22	22	55	55	22	22	22	55	55	22	22
Tested to show arc flash hazard risk category as referenced by NFPA70E		—	—	—	—	Yes	—	—	—	—	Yes	—	—	—	—
Breaking Time		25 to 30 ms (with no intentional time delay) 9 ms for L and LF
Closing Time		< 50 ms
Sensor Rating		400–800 A					600–1200 A					800–1600 A
Endurance Rating (C/O Cycles) (with no maintenance)	Mechanical	12,500
Endurance Rating (C/O Cycles) (with no maintenance)	Electrical	2,800

Ratings for ANSI C37 Certified Masterpact MTZ1 Circuit Breakers
Frame Rating		800 A
Interrupting Rating Code		N1
Number of Poles		3/4
Interrupting Current (kAIR)	254 Vac 60 Hz	42
	508 Vac 60 Hz	42
	635 Vac 60 Hz	—
Short-Time Withstand Current (kA)	Vac 60 Hz, 0.5 s	42
Built-In Instantaneous Override (Peak kA ±10%)		—
Close and Latch Ratings (Peak kA)	Vac 60 Hz	90
Tested to show arc flash hazard risk category as referenced by NFPA70E		—
Breaking Time (with no intentional time delay)		25 to 30 ms
Closing Time		< 50 ms
Sensor Rating		400 to 800 A
Endurance Rating (C/O Cycles) (with no maintenance)	Mechanical	12,500
Endurance Rating (C/O Cycles) (with no maintenance)	Electrical	2800

Ratings for IEC 60947-2 Rated Masterpact MTZ1 Circuit Breakers
Frame Rating			800/1000 A				1250/1600 A
Interrupting Rating Code			H1	H2	H3	L1	H1	H2	H3
Ultimate Breaking Capacity (kA)	Icu	220/415 Vac, 50/60 Hz	42	50	65	150	42	50	65
		440 Vac, 50/60 Hz	42	50	65	130	42	50	65
		525 Vac, 50/60 Hz	42	42	—	100	42	42	—
		690 Vac, 50/60 Hz	42	42	—	25	42	42	—
		1150 Vac, 50/60 Hz	—	—	—	—	—	—	—
Service Breaking Capacity (kA)	Ics	%Icu	100%	100%	75%	100%	100%	100%	75%
Short-Time Withstand Current (kA)	Icw	Vac 50/60 Hz, 1 s	42	42	50	10 x In	42	42	50
Built-In Instantaneous Override (kA ±10%)			—	90	110	10	—	—	110
Rated Making Capacity (Peak kA)	Icm	220/415 Vac, 50/60 Hz	88	105	145	330	88	105	145
		440 Vac, 50/60 Hz	88	105	145	286	88	105	145
		525 Vac, 50/60 Hz	88	88	—	200	88	88	—
		690 Vac, 50/60 Hz	88	88	—	52	88	88	—
		1000 Vac, 50/60 Hz	—	—	—	—	—	—	—
Breaking Time		ms	25 to 30 ms (with no intentional time delay) 9 ms for L and LF
Closing Time		ms	50
Sensor Rating			400 to 800 A
Endurance Rating (C/O cycles) (with no maintenance)		Mechanical	12,500	12,500	10,000	12,500	12,500	12,500	10,000
		Electrical 440 V	6000	6000	6000	3000	6000	6000*	6000*
		Electrical 1000 V	—	—	—	—	—	—	—