Complete integrated protection and

management of medium and large motors

The MultilinTM 469 Motor Protection System, a member of the SR family of relays,

provides protection, control, simplified configuration and advanced communications in

a cost effective industry leading draw-out construction. Designed for medium voltage

motors, the 469 delivers advanced protection with customizable overload curves and

single CT differential protection for added flexibility. The 469 also provides simplified

configuration using the Motor Settings Auto-Configurator, providing a quick and easy

set-up of motor parameters. Coupled with advanced protection and diagnostics, the 469

provides users the flexibility of multiple communication protocols allowing integration

into new and existing control networks.

Protection and Control

The 469 is a digital motor protection system designed to protect and manage

medium and large motors and driven equipment. It contains a full range of

selectively enabled, self contained protection and control elements as

detailed in the Functional Block Diagram and Features table.

Motor Thermal Model

The primary protective function of the 469 is the thermal model with six key elements:

• Overload Curves

• Unbalance Biasing

• Hot/Cold Safe Stall Ratio

• Motor Cooling Time Constants

• Start Inhibit and Emergency Restart

• RTD Biasing