Basler Electric BE1-59N User Manual

INSTRUCTION MANUAL

FOR

GROUND FAULT OVERVOLTAGE RELAY

BE1-59N

Publication: 9171400990

Revision: K 10/13

INTRODUCTION

This instruction manual provides information about the operation and installation of the BE1-59N Ground Fault Overvoltage Relay. To accomplish this, the following information is provided:

• General Information and Specifications

• Controls and Indicators

• Functional Description

• Installation

• Testing

WARNING!

To avoid personal injury or equipment damage, only qualified personnel should perform the procedures in this manual.

NOTE

Be sure that the relay is hard-wired to earth ground with no smaller than 12 AWG copper wire attached to the ground terminal on the rear of the unit case. When the relay is configured in a system with other devices, it is recommended to use a separate lead to the ground bus from each unit.

9171400990 Rev K BE1-59N Introduction i

First Printing: November 1986

Printed in USA

October 2013

CONFIDENTIAL INFORMATION

of Basler Electric, Highland Illinois, USA. It is loaned for confidential use, subject to return on request, and with the mutual understanding that it will not be used in any manner detrimental to the interest of Basler Electric.

It is not the intention of this manual to cover all details and variations in equipment, nor does this manual provide data for every possible contingency regarding installation or operation. The availability and design of all features and options are subject to modification without notice. Should further information be required, contact Basler Electric.

BASLER ELECTRIC

12570 STATE ROUTE 143

HIGHLAND IL 62249 USA

http://www.basler.com, info@basler.com

PHONE +1 618.654.2341 FAX +1 618.654.2351

ii BE1-59N Introduction 9171400990 Rev K

REVISION HISTORY

Revision and Date

Change

The following information provides a historical summary of the changes made to the BE1-59N instruction manual (9171400990). Revisions are listed in reverse chronological order.

Manual

K, 10/13

J, 01/2013

H, 04/09

G, 09/07

F, 04/02

E, 12/01

D, 01/93

—, 11/86

• Added instantaneous timing characteristic for 50-Hz relays.

• Updated case and cover drawings in Section 4.

• This revision letter not used.

• Corrected misalignment of data columns below Figure 1-4.

• Updated Storage statement in Section 4, Installation.

• Updated Output Contact ratings in Section 1.

• Moved content of Section 6, Manual Change Information to Manual

Introduction.

• Updated front panel illustrations to show laser graphics.

• Moved Testing content of Section 4, Installation to Section 5, Testing.

• Added manual part number and revision to all footers.

• Updated power supply burden data in Section 1.

• Updated Target Indicator description in Section 3.

• Added GOST-R to Section 1, General Information.

• Revised the power supply information in Sections 1 and 3.

• Updated power supply information in the style chart on page 1-3 and

in the example on page 1-2.

• Updated pickup voltage ranges and accuracies on page 1-4.

• Updated power supply description paragraphs on page 3-3.

• Updated unit case covers on pages 4-9 and 4-10.

• Updated drawings of front cover to show the new pushbutton

switches instead of the thumbwheel switches.

• New style chart (new option 1-2 and expanded option 1-1).

• Restructured the entire manual to conform to manual updates.

• Accuracy specification for the Definite Timing Characteristic was

clarified and upgraded on page 1-4.

• Output contact specifications were updated.

• Incorporated new timing option F7 in the manual.

• K was clarified for the various options on page 2-3.

• Accuracy specification for the Inverse Timing Characteristic was

clarified and upgraded on page 1-4.

• Initial release

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iv BE1-59N Introduction 9171400990 Rev K

SECTION 1 • GENERAL INFORMATION ................................................................................................ 1-1

PURPOSE ........................................................................................................................................... 1-1

APPLICATION .................................................................................................................................... 1-1

High Resistance Grounding .......................................................................................................... 1-1

Ungrounded Systems ................................................................................................................... 1-2

MODEL AND STYLE NUMBER .......................................................................................................... 1-2

Style Number Example ................................................................................................................. 1-3

SPECIFICATIONS .............................................................................................................................. 1-3

Voltage Sensing Inputs ................................................................................................................. 1-3

Undervoltage Sensing Input Range ............................................................................................. 1-4

Pickup Accuracy ........................................................................................................................... 1-4

Dropout ......................................................................................................................................... 1-4

Timing Characteristics .................................................................................................................. 1-4

Output Contacts ............................................................................................................................ 1-4

Power Supply................................................................................................................................ 1-5

Target Indicators ........................................................................................................................... 1-5

Type Tests .................................................................................................................................... 1-5

Physical ........................................................................................................................................ 1-6

Agency Recognition/Certification.................................................................................................. 1-6

SECTION 2 • CONTROLS AND INDICATORS ....................................................................................... 2-1

INTRODUCTION ................................................................................................................................. 2-1

SECTION 3 • FUNCTIONAL DESCRIPTION ........................................................................................... 3-1

INTRODUCTION ................................................................................................................................. 3-1

INPUTS ............................................................................................................................................... 3-1

FILTERS ............................................................................................................................................. 3-1

OVERVOLTAGE COMPARATOR ...................................................................................................... 3-1

DEFINITE TIME DELAY (OPTIONAL) ................................................................................................ 3-1

INVERSE TIME DELAY (OPTIONAL) ................................................................................................ 3-2

REFERENCE VOLTAGE CIRCUIT .................................................................................................... 3-2

UNDERVOLTAGE ELEMENT (OPTIONAL)....................................................................................... 3-2

Undervoltage Operation ............................................................................................................... 3-2

Undervoltage Inhibit ...................................................................................................................... 3-2

OUTPUTS ........................................................................................................................................... 3-2

PUSH-TO-ENERGIZE OUTPUT PUSHBUTTONS ............................................................................ 3-2

POWER SUPPLY STATUS OUTPUT ................................................................................................ 3-3

POWER SUPPLY ............................................................................................................................... 3-3

TARGET INDICATORS ...................................................................................................................... 3-3

Internally Operated Targets .......................................................................................................... 3-3

Current Operated Targets ............................................................................................................ 3-3

SECTION 4 • INSTALLATION.................................................................................................................. 4-1

INTRODUCTION ................................................................................................................................. 4-1

RELAY OPERATING GUIDELINES AND PRECAUTIONS ............................................................... 4-1

MOUNTING ......................................................................................................................................... 4-1

CONNECTIONS .................................................................................................................................. 4-9

MAINTENANCE ................................................................................................................................ 4-12

STORAGE ......................................................................................................................................... 4-12

SECTION 5 • TESTING ............................................................................................................................ 5-1

INTRODUCTION ................................................................................................................................. 5-1

OPERATIONAL TEST ........................................................................................................................ 5-1

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vi BE1-59N Introduction 9171400990 Rev K

SECTION 1 • GENERAL INFORMATION

Vpri

sec)(

PURPOSE

The available fault current for single-phase-to-ground faults is very limited for ungrounded systems and systems, which are grounded through a high resistance. This current limiting reduces the possibility of extensive equipment damage, and eliminates the need for a neutral breaker by reducing the fault current below the level required to sustain an arc. However, it remains important to detect and isolate singlephase-to-ground faults in order to prevent their evolution into more dangerous faults such as phase-tophase-to-ground and three-phase-to-ground faults. Sensitive voltage relays can be used to detect ground faults where the fault current is very small. The BE1-59N Ground Fault Overvoltage Relay is especially suited to this task.

APPLICATION

High Resistance Grounding

A common method of grounding an ac generator is to connect a distribution transformer between the neutral of the generator and the station ground. The distribution transformer's primary voltage rating is equal to, or greater than, the generators rated line-to-neutral voltage. The distribution transformer secondary is rated at 200/240 Vac or 100/120 Vac, and a resistor is connected across the secondary winding. When reflected through the transformer, the resistor is effectively a high resistance.

Where: Rp is the effective primary resistance

N is the turns ratio of the distribution transformer

To determine resistor sizing:

• Determine the thermal limit P (in watts) of the voltage transformers.

is the actual value of the secondary resistor

Rp = Rs x N2

• Use

120V VT secondary in a worst-case condition.

• Size the watt rating of the resistor for 1/3 of the VT thermal limit to keep the resistor from excessive heating. A smaller watt rating can be used if tripping for a ground condition.

Available single-phase-to-ground fault current at the generator terminals is greatly reduced by the high effective resistance of the distribution transformer and secondary resistor. The distribution transformer provides isolation for the protection scheme and reduces the voltage to a convenient level.

The BE1-59N Ground Fault Overvoltage Relay is connected across the secondary resistor to detect the increase in voltage across the distribution transformer caused by a ground fault in the generator stator windings. A ground fault at the generator terminals will result in rated line-to-neutral voltage across the transformer primary, while ground faults near the neutral will result in lower voltages. The overvoltage relay setpoint must be higher than any neutral voltage caused by normal unbalances in order to avoid nuisance trips. This will allow a certain percentage of the stator windings to go unprotected by the overvoltage relay. The overvoltage relay function typically protects 90 to 95% of the generator stator windings.

The BE1-59N Ground Fault Overvoltage Relay monitors the fundamental frequency (50 or 60 Hz) voltage, which accompanies a ground fault, but is insensitive to the third harmonic voltage present during normal operation. One hundred percent protection of the generator stator windings is obtainable with the optional overlapping undervoltage element. The under voltage element is tuned to the third harmonic voltage which is present in the generator neutral under normal conditions. The undervoltage element detects the reduction of the normal third harmonic voltage, which accompanies a ground fault near the neutral point of the generator.

An undervoltage inhibit feature is included with the third harmonic undervoltage element. This feature supervises the operation of the ground fault relay to prevent operation during startup and shutdown by monitoring the generator terminal voltage.

to determine resistance in ohms, where Vsec = 120 x 3 = 360V. This assumes a

9171400990 Rev K BE1-59N General Information 1-1

Ungrounded Systems

The BE1-59N Ground Fault Overvoltage Relay is used to detect ground faults on ungrounded threephase-three-wire systems. The relay is connected as shown in Figure 1-1 . A set of voltage transformers are wired with a grounded wye primary and a broken delta secondary. The BEl-59N is connected across the broken delta. It is often necessary to connect a resistor across the broken delta to avoid ferroresonance.

Grounded wye/broken delta voltage transformers act as a zero sequence filters by summing the three phase voltages. Under normal conditions, this sum is zero. When a ground fault occurs, the BE1-59N Ground Fault Overvoltage Relay will detect the presence of the secondary zero sequence voltage (3V

The BE1-59N Ground Fault Overvoltage Relay greatly reduces the risk of equipment damage by detecting and isolating the first ground on an ungrounded system.

Figure 1-1. Ungrounded 3-Phase, 3-Wire System

MODEL AND STYLE NUMBER

BE1-59N electrical characteristics and operational features are defined by a combination of letters and numbers that make up the style number. Model number BE1-59N designates the relay as a Basler Electric Ground Fault Overvoltage Protective Relay. The model number, together with the style number, describes the options included in a specific device and appears on the front panel, draw-out cradle, and inside the case assembly.

The style number identification chart for the BE1-59N relay is illustrated in Figure 1-2.

1-2 BE1-59N General Information 9171400990 Rev K

Figure 1-2. BE1-59N Style Identification Chart

Style Number Example

If a BE1-59N relay has a style number of A5F–F6J–D2S3F, the relay has the following features:

A -------- Single-phase voltage sensing input

5 -------- 120 Vac, 60 Hz nominal sensing voltage input with 1 to 20 Vac pickup range

F -------- Two output relays with normally open (NO) contacts (one overvoltage and one undervoltage)

F6 ------ Inverse time delay for overvoltage and definite time delay for undervoltage

J -------- Relay control power is 125 Vdc or 120 Vac, nominal

D -------- Two current operated target indicators (one per function)

2 -------- Undervoltage element range 0.1 to 2.5 Vac (low range with sensing input 5)

S -------- Push-to-energize outputs

3 -------- Two normally-open auxiliary output relays (one per function)

F -------- Semi-flush mounting case

SPECIFICATIONS

BE1-59N electrical and physical specifications are listed in the following paragraphs.

Voltage Sensing Inputs

Maximum continuous rating: 360 Vac for 100/120 Vac input, 480 Vac for 200/240 Vac input, with a maximum burden of 2 VA for each input.

9171400990 Rev K BE1-59N General Information 1-3

Undervoltage Sensing Input Range

High Range: 0.5 to 12 Vac (sensing input range 1, 2, 5, or 6) or 1.0 to 24 Vac

(sensing input range 3, 4, 7, or 8).

Low Range: 0.1 to 2.5 Vac (sensing input range 1, 2, 5, or 6) or 0.2 to 5.0 Vac

(sensing input range 3, 4, 7, or 8).

Pickup Accuracy

1 to 24 Vac range: ±2% or 20 millivolts All other ranges: ±2% or 10 millivolts

Overvoltage Sensing Input Range

Ranges selectable by unit type for 50 or 60 Hz operation: 1 to 20 Vac, 10 to 50 Vac, 2 to 40 Vac, 20 to 100 Vac.

Pickup Accuracy

120 Vac (sensing input range 1, 2, 5, or 6): ±2% or 100 millivolts, whichever is greater 240 Vac (sensing input range 3, 4, 7, or 8): ±2% or 200 millivolts, whichever is greater

Dropout

98% of pickup within 7 cycles.

Timing Characteristics

Instantaneous: Less than 70 milliseconds (60-Hz relays) or less than 84 milliseconds

(50-Hz relays) for a voltage level that exceeds the pickup setting by 5% or 1 volt, whichever is greater

Definite: Adjustable from 00.1 to 99.9 seconds, in steps of 0.1 seconds.

Accuracy is within 2% or 100 milliseconds, whichever is greater. (A setting of 00.0 provides instantaneous timing.)

Inverse: Response time decreases as the difference between the monitored

voltage and the setpoint increases. The inverse time characteristics switch is adjustable from 01 to 99 in 01 increments. Each position corresponds to a specific curve except 00, which is instantaneous.

Accuracy is within ±5% or 25 milliseconds (whichever is greater) of

the indicated time for any combination of the time dial and within ±2% of the voltage magnitude or 100 millivolts (for the 120 Vac sensing range) or 200 millivolts (for the 240 Vac sensing range) (whichever is greater) from the actual pickup value. Inverse time is repeatable within ±2% or 25 milliseconds (whichever is greater) for any time dial or pickup setting. The characteristic curves are defined in Figures 1-3 and 1-4.

Output Contacts

Resistive Ratings

120 Vac: Make, break, and carry 7 Aac continuously 250 Vdc: Make and carry 30 Adc for 0.2 s, carry 7 Adc continuously,

break 0.3 Adc

500 Vdc: Make and carry 15 Adc for 0.2 s, carry 7 Adc continuously,