Category: GE

Applications

• Suitable for Medium to Large HP Induction Motors (typically; 500kW-1MW,

650-1300 HP) found in oil & gas, mining & metals, cement, and wastewater applications

• Medium to large two-speed, VFD-driven and cyclic loading motors

• For high inertia loads and reduced-voltage starting motors

• Retrofit solution as a direct replacement (same mechanical form factor) for

Multilin 169. 269. 269Plus and 369 series relays

Retrofit Solutions

The Multilin 859 has been designed as a direct replacement and upgrade, matching the

height, width depth, to older Multilin 169. 269. 269Plus and 369 protection and control

devices.

The 859 fits the same mechanical cutout and uses the same terminal blocks as existing

369 relays, eliminating the need to rewire the device. For other relays, one-to-one wire

maps are provided to reduce installation and commission times.

The 859 eliminates the need to modify existing cut-outs or wiring, and does not require

re-engineering or drawing changes. The unified 8 Series setup and configuration tool

further simplifies the upgrade process with automated setting file conversion, minimizing

system downtime and commissioning time.

Key Benefits

• Utilizing GE Vernova’s proven Thermal Model for reliable protection of AC induction

motors

• With a depth of 3.5”, the 859 is ideal for MCCs with shallow depths or space constraints

• Detachable display can be mounted up to 15 feet away from the device, allowing for

greater installation flexibility

• Large graphical color LCD display for enhanced operability, with user-configurable

single line diagrams for local control, system status and metering

• Integrated condition monitoring based on Electrical Signature Analysis to deliver

detailed motor health monitoring and Predictive analytics to increase motor life

• CyberSentry™ Advanced Security including features such as AAA, Radius, RBAC, and

Syslog, helping to enable NERC® CIP compliance

• Safe and reliable motor re-start on ‘down hole’ pump applications. Unique back spin

detection feature detects flow reversal on a pump motor, enabling timely and safe

motor restarting

• Single setup & configuration software, reducing training & commissioning time

• Customer Support available 24/7. available in multiple languages

MULTILIN 859 Comprehensive, Compact Motor Protection & Management for Medium

and Large Motors

The Multilin 859 relay is a member of the Multilin 8 Series protective relay platform,

designed for the protection, control and management of medium and large power rating

induction motors. It has been designed for space constrained applications, where

a shallow depth is required, or as a direct replacement for existing Multilin 169. 269.

269Plus and 369 motor protection relays.

Utilizing the same field proven hardware and protection and control algorithms of the

Multilin 8 Series, the 859 delivers advanced features including high-speed protection,

customizable programmable logic, and advanced motor monitoring and diagnostics – all

in a fixed mount, slim design.

With extensive communication capabilities the 859 easily integrates into new or existing

process control systems, enabling operationally focused motor management and control.

SM Start Sequence Control

The 869 Start Sequence Control function provides:

• Controlled application of a DC field to the rotor winding for both brush

type and brushless synchronous motors.

The start sequence function is comprised of three field application

control methodologies:

– Slip-frequency based for brush-type motor applications.

– Timer-based for both brushless and brush-type motor applications.

– Reluctance-torque based synchronization for brush-type motor applications.

• Incomplete start sequence protection to trip/alarm if the starting

sequence is not completed within a set time.

• Load application relay functionality enabling motor loading following

the DC field application and unloading following a trip and/or loss of

synchronization (pole slipping).

• Start sequence control when the motor enters re-synchronization mode.

SM Field Overcurrent/ Undercurrent

The 869 relay provides monitoring of overcurrent and loss of DC field

excitation input to the rotor of a synchronous motor. These elements

respond to DC current input from the direct current transducer.

SM Field Overtemperature

The 869 relay provides protection of the rotor winding against overheating

by exploiting the direct proportionality between temperature and

resistance. This elements responds to rotor resistance to detect rotor

temperature. When magnitude of the field resistance or temperature

exceeds the Pickup level for the time specified by the Pickup Delay setting.

SM Field Overvoltage/ Undervoltage

Excitation system output voltage to the rotor is monitored using these

elements, corresponding to DC Field voltage measured across the field

winding or exciter terminals. DC voltage is brought to the relay terminals

through the voltage divider network, provided with the relay.

Synchronous Motor Applications

The 869 is equipped to protect and control synchronous machines

without the need for external hardware. All protection functions essential

to the synchronous motor during asynchronous operation while starting

up, during normal and overload operations and under fault conditions

are available. In addition to stator  protection and control, the relay

provides protection and monitoring of exciting rotor during pull-out or

loss of synchronism condition with elements like Out-of-Step, Loss-of

Field, Reactive Power, and Power Factor. With its well established and

matured Thermal Model, it prevents overheating of both stator and rotor

windings during both synchronous and asynchronous operation. During

asynchronous operation or startup, the thermal model with VD (voltage

dependent) function provides protection against excessive heating in the

damper winding due to stalled or locked rotor conditions.

Cyclic Load Motor Applications

Input currents of a motor driving  cyclic  load  can vary between very low

to above the maximum allowable current during a load cycle. Variation in

current magnitude results in motor heating and cooling depending on the

heat and cooling time constants. Thermal overload protection response

is made adaptive to the cyclic load based on the cooling time constants.

In addition, to provide more accurate overload thermal model response

to cyclic load, the input currents to the thermal model are averaged over

the settable duty cycle interval. With a reciprocating load application, the

number of cycles to average can be determined from current waveform

capture using the Oscillography/Datalogger features in the 869 motor

protection relay.

VFD-Driven Motor Applications

The Multilin 869 provides protection for motors fed through VFDs (Variable

Frequency Drives). A wide range of the frequency tracking (3-72Hz) allows

the 869 to track the motor frequency and adjust its sampling rate to

accurately measure phasors. An advanced algorithm allows switchable

current and voltage tracking in case VFD is bypassed.

Thermal protection also considers the extra heating generated by the

higher harmonics due to VFD to achieve the accurate response to the

actual motor heating. RMS currents fed to the various motor protection

elements are further processed through the averaging filter to eliminate

oscillations in current signals to ensure the security.

Additionally, users may indicate a  starting  VFD  frequency  that  helps

the device to track the motor frequency faster and therefore accurately

measures the phasor quantities, which, otherwise, could cause delayed or

false protection operation of the protection.

Multilin 869 Overview

The Multilin 869 Motor Protection System is a protection device

designed for the management, protection and control of medium to large

horsepower motors. The 869 provides comprehensive protection and

control of various types of motors with different loads they run.

Protection & Control

As part of the 8 Series family, the Multilin 869 provides superior protection

and control. The 869 offers comprehensive protection and control solutions

for medium and large motors for various applications. It contains a full range

of selectively enabled, self contained protection and control elements.

Recent enhancements include the following:

Starting Control

• Start sequence control

• Reluctance torque synchronization

• Incomplete start sequence

• Stabilizing feature

• Auto loading and unloading feature

Squirrel Cage Rotor Thermal Protection (separate from the main

thermal model)

• Time vs speed curve based

• Reduced voltage starting feature

Enhanced Thermal Protection with Speed Biasing

Enhanced power factor protection

• Ride-through feature – directly trips motor

• Resynchronization feature – allows motor to re-synchronize instead of

tripping

High-Inertia Load Applications

The voltage dependent overload curve feature in Thermal Model is

tailored to protect motors which are used in high inertia load applications.

Voltage is continually monitored when the motor is started and during

acceleration. The thermal limit curve is then adjusted accordingly. This

enables the Multilin 869 to distinguish between a locked rotor condition,

an accelerating condition and a running condition.

This feature acts as an additional check of the amortisseur, or squirrel

cage winding rotor heating. This feature uses estimated speed-dependent

thermal capacity used (actual value ‘’ and compares this value to the

Thermal Capacity Used calculated by the current-based and RTD Bias

(when Enabled) methods. The larger of the three values is used from that

point onward.