Eaton LZM series molded case circuit breaker

Product Overview

The Eaton LZM series is a low-voltage molded case circuit breaker and isolating switch, covering 15~1000A, designed for high-density residential, commercial, and industrial power distribution. It is standardized in four compact frameworks to reduce inventory and design costs.

Core parameters

Framework and rated current

Maximum rated current of frame model

LZM1 160A

LZM2 300A

LZM3 630A

LZM4 1000A

Breaking capacity (400/415V)

Basic type: 25kA

Comfort type: 36kA

Standard type: 50kA

Extremes and Standards

Number of poles: 3 poles, 4 poles

Neutral wire protection: * * 100%/60% * * phase current

Execution standard: IEC/EN 60947-2

Release unit

Thermomagnetic release A

Overload: 0.8~1 × In

Short circuit: 6-10 × In

Applicable: Conventional cable and system protection

Electronic release AE

Overload: 0.5~1 × In, with LED indicator

Short circuit: 2~12 × In

Application: High precision, selectivity, and generator protection

Product type

Circuit breaker LZM: overload+short circuit protection, can be equipped with various types of trip and accessories

Isolation switch LN: only has isolation function, can be remotely disconnected, without protective tripping

Attachment system

Auxiliary contacts: standard HIN, fault indication HIA, front snap fit installation

Release attachment

Under voltage trip XU: voltage drop * * 35%~70% * * trip

Split excitation trip XA: remote pulse circuit breaker

Operating attachments

Door link rotating handle: IP66 protection, padlockable

Remote operation XR: two-wire/three wire control, closing delay of 60-100ms

Installation accessories: 35/75mm guide rail buckle, insulation enclosure, spacer block, wiring terminal

Installation and Environment

Installation: front unified position, buckle type, reducing costs

Temperature: -25~+70 ℃, * * 50 ℃ * * Capacity reduction required according to the coefficient

Spacing: The minimum distance between LZM4 and other frames is 15mm

Wiring: Box/Tunnel Terminal, Supports Cu/Al Cable, Maximum 300mm ²

Engineering characteristics

Selectivity: The upper and lower circuit breakers cooperate, and the fault section trips independently without affecting other circuits

Backup protection: LZMN current limiting current is used as the upper protection for high short-circuit current fields

Minimum cross-section of cable

LZM1：≥10mm²

LZM2：≥10mm²

LZM3：≥16mm²

LZM4：≥95mm²

lifespan

Mechanical: LZM1/2: 10000 times; LZM4: 5000 times

Electrical: LZM1/2:200 times under AC-23B; LZM4: 100 times

Key questions and answers

Question 1: How many frame specifications are there for the LZM series? What are the corresponding maximum current and breaking capacity?

Answer: There are a total of four frameworks. LZM1（160A）、LZM2（300A）、LZM3（630A）、LZM4（1000A）； The maximum breaking capacity of the entire series can reach 50kA (415V).

Question 2: What are the core differences between thermal magnetic release A and electronic release AE in terms of protection range and applicable scenarios?

Answer: Thermomagnetic A: Overload 0.8~1 × In, short circuit 6~10 × In, low cost, used for conventional cable/system protection; Electronic AE: Overload 0.5~1 × In, short circuit 2~12 × In, equipped with LED and microprocessor, higher accuracy, suitable for selective protection, generators, and high-precision distribution scenarios.

Question 3: How to use LZM circuit breaker in high temperature environment? How to reduce capacity at 50 ℃?

Answer: The device allows operation at * * -25~+70 ℃, with 40 ℃ as the baseline; At 50 ℃, the thermomagnetic type needs to be multiplied by a capacitance reduction factor of 0.93-0.98, while the electronic type LZM4 does not require a capacitance reduction factor; Actual load current=rated current x corresponding temperature coefficient.