Basler Electric BE1-59NC User Manual

INSTRUCTION MANUA L

FOR

NEUTRAL OVERVOLTAGE RELAY

BE1-59NC

Publication: 9279400990 Revision: D 03/14

INTRODUCTION

This instruction manual pr o v ides infor mation about the operation an d ins ta lla tio n o f the BE1-59NC Neutral 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 inj ury or equipment damage, only qualified personnel should perform the procedures in this manual.

NOTE

Be sure that the re lay is ha r d-wir ed t o e ar th ground with no sma ller tha n 1 2 AWG copper wire attached t o the ground terminal o n 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.

9279400990 Rev D BE1-59NC Introduction i

First Printing: April 1994

Printed in USA

March 2014

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 intent ion of th is manual to cover a ll detai ls and variat ions in eq uipment, n or does this manu al provide data for ever y poss ibl e cont ing enc y regar di ng i nstal lat ion or operation. The avai lab il ity and des i gn 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 BE1-59NC Introduction 9279400990 Rev D

REVISION HISTORY

Revision and Date

Change

The following information provides a historical summary of the changes made to the BE1-59NC instruction manual (9279400990). Revisions are listed in reverse chronological order.

Manual

D, 03/14 C, 01/13 B, 09/07

A, 09/94

—, 04/94

• Corrected inverse and definite timing accuracies in Section 1.

• Updated case and cover drawings in Section 4.

• Updated Output Contacts ratings in Section 1.

• Moved content of Section 6, Maintenance to Section 4.

• Updated front panel illustrations to show laser graphics.

• Moved content of Section 7, Manual Change Information to manual

introduction.

• Added manual part number and revision to all footers.

• Updated cover drawings.

• Updated power supply burden data in Secti on 1.

• Updated Target Indicator description in Section 3.

• Corrected voltage sensing input range in Specifications and

throughout the manual.

• Changed Figure 1-3, Overvoltage Inverse Time Curves to divide the curves for low ranges (sensing input ranges 1, 3, 5, and 7) and high ranges (sensing input ranges 2, 4, 6, and 8).

• Corrected typographical error in Figure 4-9.

• Changed Testing Procedures, D1 and D2 Timing Options TIME DIAL

settings.

• Added Section 7.

• Initial release

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iv BE1-59NC Introduction 9279400990 Rev D

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

DESCRIPTION .................................................................................................................................... 1-1

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

Capacitor Bank Switching ............................................................................................................. 1-1

Protection ...................................................................................................................................... 1-1

Input Sensing ................................................................................................................................ 1-2

Alarms and Outputs ...................................................................................................................... 1-2

MODEL AND STYLE NUMBER .......................................................................................................... 1-3

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

SPECIFICATIONS .............................................................................................................................. 1-4

Voltage Sensing ........................................................................................................................... 1-4

Sensing Input Ranges .................................................................................................................. 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 ........................................................................................................................................ 1-5

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

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

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

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

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

FUNCTIONAL DESCRIPTION ........................................................................................................... 3-1

Inputs ............................................................................................................................................ 3-1

Filters ............................................................................................................................................ 3-1

Overvoltage Comparator .............................................................................................................. 3-1

Definite Time Delay ...................................................................................................................... 3-1

Inverse Time Delay ....................................................................................................................... 3-2

Reference Voltage Circuit ............................................................................................................. 3-2

Power Supply Status Output ........................................................................................................ 3-2

Power Supply................................................................................................................................ 3-2

Target Indicators ........................................................................................................................... 3-2

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

REQUIRED TEST EQUIPMENT ........................................................................................................ 5-1

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

E2 Timing Option .......................................................................................................................... 5-1

D1 Timing Option .......................................................................................................................... 5-3

D2 Timing Option .......................................................................................................................... 5-5

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vi BE1-59NC Introduction 9279400990 Rev D

SECTION 1 • GENERAL INFORMATION

DESCRIPTION

BE1-59NC Neutral Ov ervoltage Relays provide s ensitive protection for capaci tor banks. There are three common types of capacitor bank failures that BE1-59NC Neutral Overvoltage Relays recognize. They are:

• Unit dielectric failure

• Capacitor bank insulator failure

• Blown fuses

BE1-59NC Neutral Ov erv ol tage r e lays prot ect for ov er v oltag e due t o in ter na l volt a ge s hifts th at oc c ur as a result of these types of failures.

APPLICATION

Capacitor banks are wi dely used by utilities to mai ntain specified system vo ltage. Addition of capacitive loads at appropriate points on the system compens ate for heavy inductiv e loading that norma lly tends to reduce voltage. This addin g of leading megavars to compensate f or the lagging megavar component o f electric loads is frequ ently referred to as power factor correction. Capacitor banks must be switched in response to actual load conditions in order to obtain maximum power factor c or rec tion ben efits.

Capacitor Bank Switching

One of the common metho ds of maximizing capacitor bank benefits is by evaluating the b us voltage. A bandwidth surroundi ng the desir ed bus vo ltage lev el is est ablished. When the bus volta ge falls below the bandwidth level, the capacitor bank is switched into the circuit. When the bus voltage rises above the bandwidth level, the capacitor bank is switched out.

Protection

Protection of capacitor banks has always been diff icult. It is es pecially d ifficult to s ense failures i nside the capacitor banks because of the configuration. Experience indicates that most capacitor bank faults involve one or more insulat or failur es with arc ing ac ross groups and/or phase-to-phase inside the ba nk . In most cases, these types of faults are n ot seen by the bus differ entia l or other prot ection unless the ar cing spills over to the area between the fuses and the circuit switcher. A fault across an insulator usually means that one or more groups of parallel units are shorted. This will cause a neutral shift and unbalanced phase currents. Unbalanced phase current magnitudes are determined by the number of series connected groups . For full phase-to-neutral flashover, the maximum phase c urrent is three times normal capacitor bank load in the faulted phase.

One main protection conc ern is overvoltage cascading. A capac itor bank is unique in that cascading of units may take place aft er a pr edet er mined number of unit fuses have operated. Normally af t er a fus e h as blown in any other ty pe of equipment, the faulted apparatus is disconnected and us ually does not affect any remaining equipment that is in service. That is not so w ith a capacitor bank. Each fuse tha t blows to isolate the faulted unit s ets up an incr ease d voltag e str ess on the rem ainin g units (Figure 1-1). Somet ime later, the next weakest unit in that group fails. As each successive fuse blows, the voltage increases another step and rapidly causes the next unit to fail. Cascading takes place and results in serious damage to the capacitor bank and p ossible hazards to pers onn el. Wh ile the ca pacit or ban k is failing, th e stat ion in minimally affected. The v oltage is nearly normal, t he current flow is al most unaffected, and statio n relay protection is not taking any action until the failure has developed into a phase-to-phase or phase-toground fault.

A solution was to develop a protective scheme for the capacitor bank with the main emphasis on preventing overvoltage cascading. To do this, a ground fault relay or neutral shift device had to be developed that was s ensitive eno ugh to detec t blown fuses for bot h alarming a nd tripping purposes. Th e best place to obtain the s ensing information is between the neutral of the capacitor bank and ground. Voltage differentia ls bet ween t he nor mal c apaci tor ba nk s tatus and th at of one b lown f use are v ery s mall. However, BE1-59NC Neutral Overvoltage relays are sensitive enough to differentiate between these conditions and act decisively.

9279400990 Rev D BE1-59NC General Information 1-1

Figure 1-1. Ungrounded 3-Phase, 3-Wire Sys tem

Input Sensing

BE1-59NC Neutral O vervoltage relays receive the input signal from volta ge sensing devices connecte d between the capacitor bank neutral and ground. These voltage sensing devices can be potential transformers or resistor potential devices. Ideally, the voltage across each leg of a capacitor bank is balanced, and the voltage from neutral to ground is zero. If a single capacitor fails and blows the protecting fuse, an unbalanced condition occurs that shifts the neutral and creates a small but measurable voltage. Through the potential sensing devices, the neutral relay senses this voltage unbalance and reacts to g ive the appropriate signal (usual ly an alarm or trip depending on the vo ltage level).

Further loss of more c apac it ors incr eas es the neutral voltage. T he r e lay sens es th i s voltage inc re as e, an d reacts to give the appropr iate signa l. This signal is us ually a tr ip dep ending o n the voltage levels a nd how the protection scheme is designed.

Alarms and Outputs

Sensitive settings on the relay are used as an a larm to alert that a fuse has blown and maintenance is required. They woul d be typically set at a leve l corresponding to the vol tage rise caused by one b lown fuse. The second out put would have a s etting that would be set to trip the capacitor bank off t he bus or line when the voltage exce eds 110% of the nom inal capacitor bank volt age. This setting depe nds on the capacitor bank size and configuration.

1-2 BE1-59NC General Information 9279400990 Rev D

MODEL AND STYLE NUMBER

Electrical characteristics and operational features included in a specific relay are defined by a combination of letters and numbers that make up the style number. Mod el number BE1-59NC designates the relay as a Basler Electric Neutral Overvoltage 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 BE1-59NC relay is illustr at ed in Figure 1-2.

Figure 1-2. Style Number Identification Chart

Style Number Example If a BE1-59NC relay has a style number of A5E–E2J–C0S1F, the relay has the following features: A -------- Single-phase voltage sensing

5 -------- 120 Vac, 60 Hz, nominal 1 to 20 Vac pickup E -------- Two output relays with normally open contacts E2 ------ Setpoint 1 Definite (0.1 to 99.9 sec.), Setpoint 2 Definite (0.1 to 99.9 sec.) J -------- 125 Vdc or 100/120 Vac power supply C -------- Internally opera ted tar gets 0 -------- None S -------- Push-to-energize outputs 1 -------- Two SPDT auxiliary output relays, one for setpoint 1 and one for setpoint 2 F -------- Semi-flush mounting case

9279400990 Rev D BE1-59NC General Information 1-3

SPECIFICATIONS

Electrical and physical specifications are listed in the following paragraphs.

Voltage Sensing

Maximum continuous rat ing : 36 0 V ac for 100 /12 0 V ac i nput, 48 0 Vac for 200/240 Vac input, with a maximum burden of 2 VA.

Sensing Input Ranges

Ranges 1 and 5: 1 to 20 Vac pickup Ranges 2 and 6: 10 to 50 Vac pickup Ranges 3 and 7: 2 to 40 Vac pickup Ranges 4 and 8: 20 to 100 Vac pickup

Pickup Accuracy

Ranges 1, 3, 5, or 7: ±2.0% or 100 millivolts, whichever is greater. Ranges 2, 4, 6, or 8: ±2.0% or 200 millivolts, whichever is greater.

Dropout

98% of pickup within 7 cycles.

Timing Characteristics

Inverse: Response time decreases as the difference between the monitored

voltage and the setpoint increases. The inverse time char acteristics switch is adjustable from 01 to 99 in 01 increments. Each position corresponds to a specific curve except 0 0, which is instantaneous. Accuracy is within ±5% or 25 milliseconds, whichever is greater.

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

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

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,