ABB T7L1250 Tmax T7 Molded Case Circuit Breaker Product Description

Overview

ABB T7L1250 belongs to the ABB Tmax T7 series molded case circuit breaker. This ABB T7L1250 is rated 1250 A frame, L breaking capacity grade, equipped with PR231/P, PR232/P or PR332/P electronic trip units, widely used in main distribution cabinets, motor control centers, industrial power skids for feeder and transformer protection, for new switchgear build, retrofit and spare‑part replacement of ABB Tmax T7 breaker systems.

Features

ABB T7L1250 adopts true RMS electronic trip unit, supports LSI / LSIG protection functions: long-time overload, short-time delay, instantaneous short-circuit and ground fault protection. This ABB T7L1250 supports adjustable protection curves, thermal memory, pre-alarm and fault recording. ABB T7L1250 can be configured as fixed type or withdrawable type, with front / rear terminal options. It supports rich accessories: auxiliary contact, alarm contact, shunt trip, undervoltage release, motor operator and communication module for Modbus, Profibus and Ethernet connection. The stored-energy operating mechanism supports local manual closing and remote electrical closing. It complies with IEC 60947‑2, GB 14048.2 standards and carries CE, CCC certifications.

Specs

• Brand: ABB

• Series: Tmax T7

• Model: T7L1250

• Rated frame current: 1250 A

• Breaking capacity: L grade

• Rated voltage: Up to 690 V AC

• Poles: 3P / 4P optional

• Trip unit: PR231/P-LS/I, PR232/P-LSI, PR332/P-LSI/LSIG

• Mechanism: Stored energy

• Mounting: Fixed / withdrawable

• Standard: IEC 60947‑2, CE, CCC

Principle

ABB T7L1250 samples three-phase current via built-in CT. The electronic trip unit calculates RMS current, thermal accumulation and short-circuit condition according to the configured protection curve. When overload, short circuit or ground fault exceeds threshold, the trip mechanism releases and separates the main contacts to cut the power circuit. Auxiliary and alarm contacts send breaker status and fault signals to PLC and SCADA system. Communication version uploads real-time current, power and fault waveform data to the power monitoring system.

Applications

ABB T7L1250 is deployed in factory main distribution boards, water treatment MCC, data center low-voltage distribution, mining and petrochemical power skids. This ABB T7L1250 breaker provides reliable overcurrent and short-circuit protection for large feeders and transformers. T7L1250 fits switchgear overhaul and spare replacement of ABB Tmax T7 1250A molded case breakers.

Installation & Maintenance Notes

Follow official ABB Tmax T7 manual during installation of ABB T7L1250. Set protection parameters matching feeder rating and coordination with upstream/downstream breakers. Keep proper terminal torque and ventilation space. Back up trip settings before replacement. After replacement, verify auxiliary contact wiring, shunt/UVT function and communication bus address. Confirm exact part number T7L1250; T7S / T7N / T7H variants have different breaking capacity and cannot be substituted directly.