Selection

Introduction

MasterPact circuit breakers are available in three frame sizes:

T-frame circuit breakers: rated up to 1600 A.
W-frame circuit breakers: rated up to 4000 A.
Y-frame circuit breakers: rated up to 6300 A.

Within each range, several sensor plugs are available to determine the maximum trip rating of each circuit breaker. In addition to a sensor plug, an adjustable rating plug is available to get lower ampacity than that available with the sensor plug.

MasterPact circuit breakers can be equipped with a variety of MicroLogic electronic trip unit configurations, ranging from basic circuit protection to more advanced relay protection and power metering capabilities. Additionally all electronic trip units within the new MicroLogic family are field interchangeable and upgradeable. Each control unit is also equipped with an interchangeable and upgradeable adjustable rating plug which is used to select the long-time pickup setting of the circuit breaker.

NOTE: MasterPact circuit breakers are ordered by sensor plug rating, not ampere trip rating. The trip rating of the circuit breaker is determined by the setting of the adjustable rating plug. Sensor plugs and rating plugs are field replaceable.

Overview of Selection Procedure

Select the completely assembled circuit breaker (circuit breaker frame plus trip unit):

Select the trip unit, rating plug, and trip unit options.
- Frame ampere rating required
- Interrupting rating required
- Sensor plug rating required
- Connections
Select circuit breaker frame options, if required.
Select cradle options, if required.

Circuit Breaker Selection Options

Model Number	NT	NW	NW
Frame type	T	W	Y (wide-construction)
Maximum frame rating (A)	1600 A	4000 A	6300 A
Maximum Interrupting Rating (kA, 50/60 Hz)
AC rating	240 V 150 kA	240 V 150 kA	240 V 150 kA
	440 V 130 kA	440 V 150 kA	440 V 150 kA
	690 V 42 kA	690 V 100 kA	690 V 100 kA
Construction
Drawout	X	X	X
Fixed	X	X	X
Termination
Rotatable rear terminals	X	X	X
Front-connected terminals	X	X	X
Accessories Available for the Circuit Breaker and Cradle
• Shunt close • Shunt trip • Undervoltage trip • Fixed time delay • Adjustable time delay • Spring-charging motor • Auxiliary contacts (standard)	• Ready-to-close contact • Overcurrent trip switch (standard) • Rack in interlock • Key locks for circuit breaker and cradle • Padlock attachment (circuit breaker plus cradle) • Mechanical interlocks • Cradle position switches		• Door interlock • Operations counter • Safety Shutter • Cradle rejection kit (standard) • Rail Padlocking
Electronic Trip Unit Features
• True RMS sensing • LSI • Ground-fault alarm (no trip) • Ground-fault trip • Ground-fault trip and programmable alarm • Adjustable rating plugs • Long-time pickup LED	• Trip indication LED • Zone-selective interlocking (ZSI) • Communications • LCD dot matrix display • Advanced user interface • Protective relay functions • Thermal imaging		• Neutral protection • Contact wear indication • Incremental fine-tuning of settings • Selectable long-time delay bands • Power measurement • Expanded memory • Enhanced power quality measurement

MicroLogic Trip Unit Selection

Design Platform Designation	Feature Type	Protection	Model Number
Basic Trip Unit	Basic	LS0	2.0
Basic Trip Unit	Basic	LSI	5.0
Trip Unit with Ammeter	A	LS0	2.0A
		LSI	5.0A
		LSIG	6.0A
Trip Unit with Power Metering	P	LSI	5.0P
Trip Unit with Power Metering	P	LSIG	6.0P
Trip Unit with Harmonic Metering	H	LSI	5.0H
Trip Unit with Harmonic Metering	H	LSIG	6.0H

Factory Assembled Circuit Breakers and Switches

T-Frame Selection

T-Frame Circuit Breakers

Frame Rating (A)	Model Number	Interrupting Rating (kA)				Sensor Plug Rating (A)
Frame Rating (A)	Model Number	240 V	440 V	690 V	1000 V	Sensor Plug Rating (A)
800 A	NT08H1	42	42	42	—	250, 400, 630, 800
800 A	NT08L1	150	130	25	—	250, 400, 630, 800
1000	NT10H1	42	42	42	—	400, 630, 800, 1000
1000	NT10L1	4150	130	25	—	400, 630, 800, 1000
1250	NT12H1	42	42	42	—	630, 800, 1000, 1250
1600	NT16H1	42	42	42	—	800, 1000, 1250, 1600

Non-Automatic T-Frame Switches

Frame Rating (A)	Model Number	Interrupting Rating (kA)*				Short-Time (0.5 s) Rating (kA)
Frame Rating (A)	Model Number	240 V	440 V	690 V	1000 V	Short-Time (0.5 s) Rating (kA)
800	NT08HA	42	42	42	—	42
1000	NT10HA	42	42	42	—	42
1250	NT12HA	42	42	42	—	42
1600	NT16HA	42	42	42	—	42

W-Frame Selection

W-Frame Circuit Breakers

Frame Rating (A)	Model Number	Interrupting Rating (kA)				Sensor Plug Rating (A)
Frame Rating (A)	Model Number	240 V	440 V	690 V	1150 V	Sensor Plug Rating (A)
800	NW08N1	42	42	42	—	400, 630, 800
	NW08H1	65	65	65	—	400, 630, 800
	NW08H2	100	100	85	—	400, 630, 800
	NW08L1*	150	150	100	—	400, 630, 800
	NW08H10*	—	—	—	50	400, 630, 800
1000	NW10N1	42	42	42	—	400, 630, 800, 1000
	NW10H1	65	65	65	—	400, 630, 800, 1000
	NW10H2	100	100	85	—	400, 630, 800, 1000
	NW10L1*	150	150	100	—	400, 630, 800, 1000
	NW10H10*	—	—	—	50	400, 630, 800, 1000
1250	NW12N1	42	42	42	—	630, 800, 1000, 1250
	NW12H1	65	65	65	—	630, 800, 1000, 1250
	NW12H2	100	100	85	—	630, 800, 1000, 1250
	NW12L1*	150	150	100	—	630, 800, 1000, 1250
	NW12H10*	—	—	—	50	630, 800, 1000, 1250
1600	NW16N1	42	42	42	—	800, 1000, 1250, 1600
	NW16H1	65	65	65	—	800, 1000, 1250, 1600
	NW16H2	100	100	85	—	800, 1000, 1250, 1600
	NW16L1*	150	150	100	—	800, 1000, 1250, 1600
	NW16H10*	—	—	—	50	800, 1000, 1250, 1600
2000 A	NW20H1	65	65	65	—	1000, 1250, 1600, 2000
	NW20H2	100	100	85	—	1000, 1250, 1600, 2000
	NW20H3*	150	150	100	—	1000, 1250, 1600, 2000
	NW20L1*	150	150	100	—	1000, 1250, 1600, 2000
	NW20H10*	—	—	—	50	1000, 1250, 1600, 2000
2500	NW25H1	65	65	65	—	1250, 1600, 2000, 2500
	NW25H2	100	100	85	—	1250, 1600, 2000, 2500
	NW25H3*	150	150	100	—	1250, 1600, 2000, 2500
	NW25H10*	—	—	—	50	1250, 1600, 2000, 2500
3200	NW32H1	65	65	65	—	1600, 2000, 2500, 3200
	NW32H2	100	100	85	—	1600, 2000, 2500, 3200
	NW32H3*	150	150	100	—	1600, 2000, 2500, 3200
	NW32H10*	—	—	—	50	1600, 2000, 2500, 3200
4000	NW40H1	65	65	65	—	2000, 2500, 3200, 4000
	NW40H2	100	100	85	—	2000, 2500, 3200, 4000
	NW40H3*	150	150	100	—	2000, 2500, 3200, 4000
	NW40H10*	—	—	—	50	2000, 2500, 3200, 4000

Automatic Switch

Frame Rating (A)	Model Number	Withstand Rating (kA)*			Instantaneous Override (kA)
Frame Rating (A)	Model Number	240 V	440 V	690 V	Instantaneous Override (kA)
800	NW08HF	85	85	85	85
1000	NW10HF	85	85kA	85kA	85
1250	NW12HF	85	85	85	85
1600	NW16HF	85	85	85	85
2000	NW20HF	85	85	85	85
2500	NW25HF	85	85	85	85
3200	NW32HF	85	85	85	85
4000	NW40HF	85	85	85	85

Non-Automatic Switch

Frame Rating (A)	Model Number	Interrupting Rating (kA)*				Short-Time (1s) Rating (kA)
Frame Rating (A)	Model Number	240 V	440 V	690 V	1150 V	Short-Time (1s) Rating (kA)
800	NW08NA	42	42	42	—	42
	NW08HA	50	50	50	—	50
	NW08HA10*	—	—	—	50	50
1000	NW10NA	42	42	42	—	42
	NW10HA	50	50	50	—	50
	NW10HA10*	—	—	—	50	50
1250	NW12NA	42	42	42	—	42
	NW12HA	50	50	50	—	50
	NW12HA10*	—	—	—	50	50
1600	NW16NA	42	42	42	—	42
	NW16HA	50	50	50	—	50
	NW16HA10*	—	—	—	50	50
2000	NW20HA	50	50	50	—	50
2000	NW20HA10*	—	—	—	50	50
2500	NW25HA	50	50	50	—	50
2500	NW25HA10*	—	—	—	50	50
3200	NW32HA	50	50	50	—	50
3200	NW32HA10*	—	—	—	50	50
4000	NW40HA	50	50	50	—	50
4000	NW40HA10*	—	—	—	50	50

Y-Frame Selection

Y-Frame Circuit Breakers

Frame Rating (A)	Model Number	Interrupting Rating (kA)			Sensor Plug Rating (A)
Frame Rating (A)	Model Number	240 V	440 V	690 V	Sensor Plug Rating (A)
5000	NW50H1	100	100	100	2500, 3200, 4000, 5000
5000	NW50H2	150	150	100	2500, 3200, 4000, 5000
6300	NW63H1	100	100	100	3200, 4000, 5000, 6300
6300	NW63H2	150	150	100	3200, 4000, 5000, 6300

Non-Automatic Switches

Frame Rating (A)	Model Number	Interrupting Rating (kA)*			Short-Time (1s) Rating (kA)
Frame Rating (A)	Model Number	240 V	440 V	690 V	Short-Time (1s) Rating (kA)
5000	NW50HA	85	85	85	85
6300	NW63HA	85	85	85	85