Schneider Electric Masterpact MT Series Air Circuit Breakers: MT08N1,

Technical Dossier

Product Details And Specifications

Schneider Electric Masterpact MT Series: Comprehensive Module Range and Technical Overview

The Schneider Electric Masterpact MT series represents the industrial-grade air circuit breaker (ACB) platform deployed across heavy-process industries including petrochemical refineries, nuclear power auxiliary systems, offshore platforms, and large-scale manufacturing facilities. Rated from 630 A to 6300 A, the MT series operates at voltages up to 690 V AC and is engineered for main incomer, bus coupler, and feeder protection duties in low-voltage main distribution switchboards (MDB). Its global installed base spans IEC 61439-compliant switchgear assemblies across Europe, Asia-Pacific, and the Middle East, making it one of the most widely maintained ACB platforms in industrial electrical infrastructure. The MT08N1 (800 A, N-frame, fixed, 3-pole) is a representative mid-range unit within this family, commonly specified in 400 V distribution boards for motor control centers and process plant incomers.

The Evolution of Masterpact MT Architecture

Schneider Electric's air circuit breaker lineage in the Masterpact family progressed through three distinct generations. The original Masterpact M series (introduced in the early 1990s) established the modular draw-out chassis concept with analog trip units. The Masterpact NT/NW generation (mid-1990s to 2010s) introduced digital Micrologic trip units (2.0, 5.0, 6.0, 7.0) with MODBUS/JBUS communication capability, enabling integration into early SCADA and DCS architectures. The current Masterpact MT generation (launched 2018) supersedes the NT/NW platform with a redesigned chassis, embedded IoT connectivity via the MicroLogic X trip unit, and native compatibility with EcoStruxure Power architecture. Key compatibility considerations: MT-frame draw-out chassis are not mechanically interchangeable with NT/NW chassis without cradle adapters; Micrologic X trip units use a different communication protocol stack than legacy Micrologic 5.0/6.0 units; and existing NT/NW installations requiring like-for-like replacement must source NT/NW stock, as MT units require switchboard modification. The MT series is currently in active production and full lifecycle support phase.

Masterpact MT Full Catalog & Functionalities (SKU List)

The following SKUs represent verified models within the Schneider Electric Masterpact MT series, organized by frame rating and pole configuration. Each entry reflects a distinct catalog reference with defined current rating, breaking capacity, and mounting type.

MT06H1: 630 A, H-frame (70 kA), fixed, 3-pole, standard incomer/feeder ACB.
MT06H13: 630 A, H-frame, draw-out, 3-pole, with MicroLogic 5.3 E trip unit.
MT06N1: 630 A, N-frame (50 kA), fixed, 3-pole, general-purpose distribution.
MT06N13: 630 A, N-frame, draw-out, 3-pole, MicroLogic 5.3 E, MODBUS ready.
MT08N1: 800 A, N-frame (50 kA), fixed, 3-pole, main incomer for MCC and MDB.
MT08N13: 800 A, N-frame, draw-out, 3-pole, MicroLogic 5.3 E trip unit.
MT08H1: 800 A, H-frame (70 kA), fixed, 3-pole, high breaking capacity feeder.
MT08H13: 800 A, H-frame, draw-out, 3-pole, MicroLogic 5.3 E, EcoStruxure compatible.
MT10N1: 1000 A, N-frame, fixed, 3-pole, standard bus coupler and incomer duty.
MT10N13: 1000 A, N-frame, draw-out, 3-pole, MicroLogic 5.3 E, MODBUS/Ethernet.
MT10H1: 1000 A, H-frame (70 kA), fixed, 3-pole, high-fault-level incomer.
MT12N1: 1250 A, N-frame, fixed, 3-pole, large feeder and bus section protection.
MT12N13: 1250 A, N-frame, draw-out, 3-pole, MicroLogic 5.3 E trip unit.
MT16N1: 1600 A, N-frame, fixed, 3-pole, main incomer for large LV switchboards.
MT16H1: 1600 A, H-frame (70 kA), fixed, 3-pole, high breaking capacity main incomer.
MT20N1: 2000 A, N-frame, fixed, 3-pole, large distribution and bus coupler duty.
MT20H1: 2000 A, H-frame, fixed, 3-pole, high-fault-level 2000 A incomer.
MT25N1: 2500 A, N-frame, fixed, 3-pole, heavy industrial main incomer.
MT32N1: 3200 A, N-frame, fixed, 3-pole, primary incomer for large LV substations.
MT40N1: 4000 A, N-frame, fixed, 3-pole, utility-scale LV main incomer.

Sourcing Hard-to-Find & Obsolete Masterpact MT Parts

Although the Masterpact MT series remains in active production, parallel demand exists for legacy NT/NW units that the MT series supersedes. DriveKNMS maintains a verified inventory of both current MT-generation units and end-of-life NT/NW references including NW08N2, NT08H1, and associated Micrologic 5.0/6.0 trip unit assemblies. For plant operators running mixed-generation switchgear, sourcing a like-for-like NT/NW replacement is frequently the only option that avoids switchboard modification costs. DriveKNMS provides: (1) cross-reference verification between MT and NT/NW chassis dimensions and cradle compatibility; (2) tested surplus stock of discontinued NT/NW references with full functional test reports; (3) trip unit exchange and recalibration services for Micrologic 2.0 through 6.0 units; and (4) long-term supply agreements for plant maintenance teams requiring guaranteed availability over 5–10 year maintenance windows. All units are sourced from decommissioned OEM-certified switchgear and undergo full dielectric and functional testing prior to dispatch.

Quality Control for the Masterpact MT Range

Air circuit breakers in the Masterpact MT series incorporate complex mechanical and electronic subsystems — including the draw-out cradle mechanism, stored-energy spring charging motor, MicroLogic X trip unit, and Bluetooth/Ethernet communication module — each of which requires dedicated verification procedures. DriveKNMS applies the following test protocol to all MT-series units processed through its facility: (1) Mechanical operation test: minimum 5 open/close cycles under no-load conditions to verify spring charging mechanism, racking mechanism engagement, and auxiliary contact sequencing; (2) Trip unit functional test: injection of simulated overcurrent, short-circuit, and earth fault signals via a calibrated secondary injection test set to verify MicroLogic X protection thresholds; (3) Insulation resistance test: 1000 V DC Megger test across all pole pairs and pole-to-frame, minimum 100 MΩ acceptance criterion; (4) Contact resistance measurement: micro-ohmmeter test on main current path, acceptance per IEC 60947-2 manufacturer limits; (5) Communication interface verification: MODBUS RTU and Ethernet/IP polling test to confirm trip unit data register integrity. All test results are documented and supplied with each unit shipment.