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Description

BE1-67 Phase Directional Overcurrent Relays are designed for the protection of transmission and

distribution lines where the direction as well as the magnitude of the fault current (or power flow) is to be

considered in the tripping decision.

BE1-67 relays are directionally controlled, microprocessor based, time overcurrent relays. The directional

element is polarized by the phase-to-phase quadrature voltage of the power system. That is, the

directional element monitoring the phase A current uses the voltage between phases B and C to

determine the direction of current (or power) flow into the fault. Then, if enough current flows in the

tripping direction of the relay, the relay will pickup, time out, and trip. The angle of maximum sensitivity for

the relay is also adjustable to allow the directional characteristic to be matched to the line and system

conditions. 

The directional characteristic of the relay is adjustable to allow the relay to be sensitive for phase faults

and to maximize sensitivity at the characteristic angle representing typical power factor.

Twelve standard time-current characteristic curves are available to aid in the coordination of this relay

with other protective devices in the system. These include seven characteristic curves that are standard in

North America and five that are compatible with British or IEC standards requirements. Any of the curves

may be switch selected to suit requirements at the time of installation.

Benefits

• AEM-2020 Analog Expansion Module- Easily connects to compatible devices

when additional analog I/O is required to meet difficult specifications.

– Rugged, potted design for the ultimate in reliability for extreme environmental

applications.

– Connects to compatible devices via CAN bus and automatically integrates into

the BESTCOMSPlus® PC software. Fast to configure, simplifying commissioning

of complicated systems.

– Combine this additional I/O with the powerful programmable logic of the DGC-2020.

DGC-2020HD, DECS-250. DECS-250N, DECS-250E, and DECS-450 and eliminate

the need for an additional PLC or other peripheral devices, saving installation

and purchasing costs.- Easily-assigned trip points for the analog inputs can be

scaled by the user to directly reflect the measured parameter.

– A wide variety of generator parameters can easily be integrated into an overall

protection and metering scheme to meet virtually any specification.

• CEM-2020 Contact Expansion Module

– The rugged, potted design of the CEM

-2020 provides ultimate reliability in extreme environments.

– Enables easy addition of contact inputs and outputs through logic, reducing the

need for external control devices, which saves both time and money.

– Connects to compatible devices via CAN bus and automatically integrates into

BESTCOMSPlus software for simple, quick configuration of complicated systems.

Overview

These expansion modules eliminate the need for expensive external devices

by providing additional contact and analog inputs and outputs to certain

Basler Electric products.

Features

• AEM-2020 Analog Expansion Module

– Eight analog inputs

– Eight resistance temperature device (RTD) inputs

– Two Type K thermocouple inputs

– Four analog outputs

– Inputs and outputs are configurable for 4 to 20 mA and 0 to 10 Vdc ranges

– Controller Area Network (CAN) communication protocol

– Compatible with DGC-2020. DGC-2020HD, DECS-250. DECS-250N,

DECS-250E, and DECS-450

• CEM-2020 Contact Expansion Module

– Ten dry contact inputs

– Twenty-four contact outputs with the CEM-2020

– Inputs and outputs programmable through BESTCOMSPlus® software

– CAN communication protocol

– Compatible with DGC-2020ES, DGC-2020. DGC-2020HD, DECS-250.

DECS-250N, DECS-250E, and DECS-450

Overview

Manual voltage controllers are an integral part of a complete excitation

system. These devices are utilized to control excitation in the event of an

automatic voltage regulator failure. Basler MVCs can isolate the automatic

voltage regulator and manually control the generator’s output.

Features

• Designed to operate with all Basler voltage regulators rated at or below

7 amperes continuous

• Completely solid state

• 120 to 240 Vac operation

• Multiple field output ratings

• Automatic voltage build-up circuit

• Small and light for easy panel or door mounting

• Available from stock

Benefits

• Provides the ability to manually control excitation in the event of

a regulator failure or sensing transformer failure. This allows the

operator to maintain power to critical and emergency loads until a

repair can be made.

• These controllers offer functionality to meet many manual backup

applications.

• Rugged field-proven designs that can be relied upon in an

emergency situation.

• Some MVCs offer remote control capability so that the operator

can be located outside the generator room.

Overview

BE1-60 relays provide reliable instantaneous response to block other devices

from incorrect operation resulting from a blown fuse or other fault in a

potential transformer circuit.

Features

• Pickup adjustable in 5% increments over a range of 5 to 50% of nominal

voltage.

• Single-phase to single-phase, single-phase to three-phase, or three

phase to three-phase sensing.

• Maximum trip time of 100 milliseconds for voltage differences greater

than three times the setting.

• Low sensing and supply burdens.

Benefits

• Flexible pickup adjustable over a range of 5 to 50% of nominal

voltage.

• Easily meet system configuration with single-phase and three

phase input configurations.

• Minimized PT (potential transformer) costs as a result of low

sensing burden.

• Reduced battery load with low burden power supply.

• Accurate, repeatable, and reliable operation.

• Simple HMI provides clear and intuitive settings for easy

configuration.

• LED targets provide clear annunciation of status.

• Easily perform in-case system and device tests using test plugs.

Trip Timing

Within the relay are two timers that control operation of the device. Timer 1 defines the delay time between

recognition of the breaker trip signal and the interrogation of the current monitoring circuits for the presence

of current. Adjustment range for this timer is 18 to 500 milliseconds.

At the same time that timer 1 is initiated, the control timer is also initiated. Figure 1-1 illustrates the trip

timing relationships. The purpose of the control timer is to increase security by limiting the response time

of the relay to a short period following any given attempt to interrupt the breaker. The control timer also

terminates the closure of the BF output relays, and breaks the seal of the seal-in circuit (if used).

Breaker failure initiate (BFI) input seal-in is selected by closing printed circuit board switch S1-3 (refer to

Section 2 for location and Section 3 for logic block diagram). This selection may be required when current

from an isolated weak source cannot be depended on to maintain the minimum signal level to the protective

relays initiating the BFI input. Such a condition can occur when the fault voltage is depressed to zero. The

seal-in feature may also counteract contact bounce.

An optional supervisory contact input to the BE1-50BF relay may be specified. When the supervisory

contact input is specified, a third timer (timer 2) is built into the relay. Timer 2 (plus associated circuitry

together with the supervisory contact) duplicates the corresponding features of the timer 1 system. This

addition allows different breaker failure times for different types of failures.

As an example, it might be desirable to use a shorter tripping time if the breaker mechanism fails to operate

(all three breaker poles failed to clear the fault). If the mechanism did operate, but only one of the poles

failed to clear, a longer breaker failure time might be appropriate. This protection can be provided by

connecting the BFI input in series with a 52a contact of the breaker to the supervisory contact input and

setting the delay on timer 2 shorter than timer 1. If the breaker mechanism failed to operate, the breaker

failure relay would be controlled by timer 2. If the breaker mechanism did operate, timer 2 would (in time)

reset and the breaker failure relay would be controlled by timer 1.

This scheme (BFI in series with 52A to supervisory input) allows for 52A or current supervision of the BF

timers 1 and 2. If 52A supervision is desired, switch S1-7 would be closed. Refer to Section 3 block diagram

for logic details.

DESCRIPTION

BE1-50BF Breaker Failure Relays are three-phase, solid state relays designed to provide protection and

security for the power system against failure of the monitored breaker.

Breaker failure relaying is the use of a current monitoring relay to determine whether or not current

continues to flow into a faulted circuit some time after a circuit breaker has been instructed to interrupt the

circuit. In the event that current continues to flow into the faulted circuit (after a defined period of time has

elapsed sufficient for the breaker to have interrupted the current), then the circuit breaker is considered to

have failed, and steps must be initiated to trip the next set of breakers up stream in the power system. The

back up scheme must be designed to isolate both the faulted circuit and the failed breaker.

Following are several reasons why a breaker fails to clear a fault:

• Trip circuit can be open (broken wire, blown fuse, open trip coil).

• Interrupting mechanism can stick, leaving a single phase of a three-phase circuit connected.

• Interrupter can flash-over due to the loss of dielectric strength through contamination or damage.

• Operating mechanism can fail to operate.

Breaker failure relays detect these conditions and initiate contingency or back up procedures.

Typically, breaker failure protection is applied to transmission and sub transmission systems. However,

breaker failure protection may be applied to any portion of the power system where failure of a circuit

breaker to operate properly could result in severe system damage or instability.