Introduction

The AVC63-12 and AVC125-10 regulate the level of excitation supplied

to the field of a conventional, brushless, synchronous generator.

Regulation is achieved by sensing the generator output voltage, converting

it to a dc signal, and comparing the signal to a reference voltage.

An error signal is developed and used to control the dc field power in

order to maintain a constant generator output.

Each regulator includes frequency compensation with selectable slope,

inverse-time overexcitation shutdown, buildup circuitry, single-phase or

three-phase voltage sensing, single-phase or three-phase shunt or

permanent magnet generator (PMG) power input, parallel droop

compensation, and an accessory input. The accessory input provides

compatibility with devices such as var/power factor controllers or excitation

limiters.

INSTALLATION

BE3 ac current sensing relays are designed for mounting on

standard DIN rails that comply to DIN-EN 50022. Mounting involves

hooking the top edge of the cutout on the base of the case over one

edge of the DIN rail. The opposite side of the cutout containing the

release clip is then pushed over the opposite side of the DIN rail. To

remove or reposition the relay, lever the release clip and move the

relay as required. BE3 relays should be installed in a dry, vibration

free location where the ambient temperature does not exceed the

operating temperature range. Connections to the relay should be

made using wire that meets applicable codes and is properly sized

for the application. Figure 1 shows the terminal connections for the

BE3-37. BE3-51. and BE3-37/51 ac current relays.

OPERATION

BE3-37 and BE3-51 ac current relays have two external, user

adjustable controls marked SET and DELAY. The BE3-37/51 has

four controls: UNDER SET, UNDER DELAY, OVER SET, and

OVER DELAY. The SET control adjusts the relay trip point. An

overcurrent trip causes the relay output to energize when the

current rises above the SET threshold. The overcurrent SET level is

adjustable from 40 to 120% (±3%) of nominal input. An undercurrent

trip causes the relay output to de-energize when the current

decreases below the SET threshold. The undercurrent SET level is

adjustable from 0 to 80% (±3%) of nominal input. Time delay is the

amount of time that elapses after the trip point is reached and when

the output relay operates.

Setting Example

A BE3-51 relay has the following settings:

SET – 120%

DELAY – 4 seconds

A trip occurs when the sensing current rises above six amperes for

four seconds. Reset occurs when the current decreases below 5.75

amperes (5% of nominal below trip setting).

INTRODUCTION

BE3 ac current relays provide current monitoring and protection in

both single-phase and three-phase systems. They are used in

applications such as motor protection, load detection, and generator

control. Undercurrent, overcurrent, and combined over/undercurrent

units are available. BE3 ac current relays operate when the

adjustable trip point is reached. A time delay control is provided with

an adjustment of 0 to 10 seconds (relay operating time is typically

200 milliseconds). This time delay may be used to prevent false

tripping when there are slight variations in the sensed current.

On overcurrent units, the output relay energizes when the input

signal exceeds the trip point. On undercurrent units, the output relay

de energizes when the input signal goes below the trip point. A red

LED indicates the state of the output relay. A green LED indicates

the condition of the power supply.

The Basler Electric AVC63-4 and AVC63-4D Voltage Regulators deliver

proven analog voltage control for generator excitation systems.

Designed for dependable operation in demanding environments, these

rugged regulators provide precise voltage regulation across the full

operating temperature range without performance degradation.

Their compact, potted design supports installation in harsh conditions

while minimizing maintenance requirements. Features such as volts-

per-hertz limiting, overexcitation shutdown, and external voltage

adjustment capability make the AVC63 series a versatile solution for

new generator installations and replacement applications.

— Product Features & Benefits

• Voltage regulation performance is constant over the entire operating

-temperature range without derating or degradation. Performance

concerns about temperature fluctuation are eliminated because the AVC

always performs.

• Potted design allows installation in harsh environments.

• Reduce or eliminate expensive service calls because of the reliable,

rugged construction.

• Volts-per-hertz limiting, overexcitation shutdown, and provisions for

external voltage adjustments make the AVC line a good fit for most

applications. It’s the “universal” regulator that reduces inventory to one

device on the shelf.

• Small size for easy installation in virtually any generator terminal box.

• Eliminate settings errors with simple adjustments.

Benefits

• A single, cost effective device for nearly any protection, automation

or control application that minimizes future design methodology

changes. As changes are needed, simply enable or modify the required

functionality and increase system capabilities with reduced efforts.

• Reduce sensory and device overload by displaying and utilizing only

what is needed for an application.

• Prioritize and ensure function confidence with Basic and Advanced

views of many features.

• The HMI Home Screen, with pinch-to-zoom, provides system status and

control to avoid HMI navigation and changing system condition issues.

• Fine tune protection and control with multi-zone configurations.

• See inside the box with Live Logic Metering to visualize functions from a

single BESTCOMSPlus® screen.

Rotational Limit Output Contacts

Two sets of SPDT output contacts indicate the rotational limits of the MOC

control potentiometer. The clockwise limit is indicated by contacts at terminals

8. 9. and 10. At the clockwise limit, the contacts at terminals 8 and 9 open

and the contacts at terminals 9 and 10 close.

The counterclockwise limit is indicated by contacts at terminals 11. 12. and

13. At the counterclockwise limit, the

contacts at terminals 11 and 12 open and the contacts at terminals 12 and

13 close.

Dynamic Braking

Dynamic braking is obtained by placing a short-circuit across terminals 5 and

7. An available accessory switch provides the necessary contact arrangement

for the raise/lower function and dynamic braking.

ACCESSORIES

MOC2XXX accessories consist of switch and dial plate sets. Each set is supplied

with a rotary, three-position, momentary-action switch with a pistol-grip handle.

For a switch with a blank dial plate, order Basler part number 9174805106.

For a switch with a dial plate labeled LOWER/OFF/RAISE and FREQUENCY

CONTROL, order Basler part number 9174805107.

For a switch with a dial plate labeled LOWER/OFF/RAISE and VOLTAGE CONTROL,

order Basler part number 9174805108.

Raise and Lower Inputs

When a raise or lower input is received, voltage is applied to the motor,

causing it to rotate and move the slider of the potentiometer.

If a raise input is received, the polarity of the applied motor voltage causes

the motor and potentiometer to rotate in the clockwise direction.

This clockwise rotation continues until 24 Vdc is removed from the motor

due to removal of the raise input or activation of the clockwise limit switch.

If a lower input is received, the polarity of the applied motor voltage causes

the motor and potentiometer to rotate in the counterclockwise direction.

This counterclockwise rotation continues until 24 Vdc is removed from the

motor due to removal of the lower input or activation of the counterclockwise

limit switch.

Dynamic Braking

Dynamic braking is obtained by placing a short-circuit across terminals 5 and

7. An available accessory switch provides the necessary contact arrangement

for the raise/lower function and dynamic braking.

Features

• Large, intuitive, customizable, touchscreen HMI (Human-Machine

Interface)

• Multi-breaker automation and control with Trip Circuit Monitoring

and Breaker Monitoring

• High analog and digital input/output counts: Up to 28 CT, 16

VT, 72 contact sense, 48 outputs or 3 Ethernet ports (pending

configuration, counts not cumulative)

• Auxiliary analog inputs

-4 to 20 mA, 0 to 10 V, 50 to 100 mV, and RTD

• Field upgradable hardware and software

• Advanced cybersecurity features

• IRIG-B, NTP, and DNP synchronized clock with battery backup

• USB-C, RS-485, copper Ethernet and fiber Ethernet ports, HSR and

PRP redundancy

• Protocol Support: Modbus®, DNP, IEC 61850, Synchrophasor,

BESTnet™Plus remote HMI, and email alerts.

• Advanced recording

-Targets and alarms

-30+ million data point Oscillography log (COMTRADE format)

with Fault Summary

-8,000-record Sequence of Events log

-Load profile recording

-Transformer Damage (51TF)

-Diagnostic log

-Demand

-Power quality

-Energy