Basler Electric BE1-87T User Manual

INSTRUCTION MANUAL

FOR

TRANSFORMER DIFFERENTIAL RELAY

BE1-87T

BE1-87T
TRANSFORMER DIFFERENTIAL
Style No. D2E A1J D1S0F
Serial No. XXXXXXXXXXXX
PUSH TO
ENERGIZE
OUTPUT
R	U
P0052-22

Publication:	9171300990
Revision:	V	03/12

INTRODUCTION

This instruction manual provides information about the operation and installation of the BE1-87T Transformer Differential relay. To accomplish this, the following information is provided:

General Information and Specifications

Controls and Indicators

Functional Description

Installation

Test Procedures

WARNING!

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

NOTE

Be sure that the BE1-87T 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 BE1-87T is configured in a system with other devices, it is recommended to use a separate lead to the ground bus from each unit.

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First Printing: June 1990

Printed in USA

Copyright © 1990-2012 Basler Electric, Highland Illinois 62249 USA

All Rights Reserved

March 2012

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.

For terms of service relating to this product and software, see the Commercial Terms of Products and Services document available at www.basler.com/terms.

BASLER ELECTRIC

12570 STATE ROUTE 143

HIGHLAND IL 62249-1074 USA http://www.basler.com, [e-mail]

PHONE [phone]

FAX [phone]

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BE1-87T Introduction

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REVISION HISTORY

The following information provides a historical summary of the changes made to the BE1-87T instruction manual (9171300990). Revisions are listed in reverse chronological order.

	Manual	Change
	Revision and Date
	V, 03/12	Updated format of Table 1-3, Power Supply Ratings, to be consistent
		with other manuals.
		Standardized case and cover drawings in Section 4.
	U, 08/11	Updated 2nd harmonic restraint specs for 5 A & 1 A CTs in Section 5.
		Updated formatting to current style used.
	T, 03/11	Updated 2nd & 5th harmonic restraint specs in Section 1.
	S, 09/10	Updated “K” type power supply burden in Table 1-3.
		Updated GOST-R statement in Section 1.
		Updated rear case drawings in Section 4.
		Removed references to extender card in Sections 4 and 5.
		Updated Storage statement in Section 4.
	R, 09/07	Replaced magnetic type targets with electronic type targets.
		Updated power supply burden data and output contact ratings.
		Updated front panel illustrations to show laser graphics.
		Moved content of Section 6, Maintenance to Section 4, Installation.
		Added GOST-R certification to Section 1, General Information.
	Q, 10/05	In Section 1, General Information, Specifications, corrected values for
		Maximum Current per Input for 1 Ampere CT Units.
		In Section 5, Test Procedures, corrected values inside CAUTION box
		for 1 AMP CT on page 5-14.
	P, 05/03	Added a thumbscrew to the figure on the manual front cover.
		Added “not all styles” to the Power Supply Output heading on page 3-
		4 as well as added “NOTE” and a text box around the second last
		paragraph on page 3-4.
		Added the new thumbscrew to Figure 4-1 and changed the height
		dimensions in Figure 4-2.
		Clarified the terminal numbers on Figure 4-6b.
		Added a shorting bar between terminals 6 & 7 in Figure 4-11.
		Added a shorting bar and normally open contact and normally closed
		contact effecting terminals 1, 2, & 5 in Figure 4-12.
		Step 13 was corrected on pages 4-31 and 4-39 to include Rw in the
		formulas.
		Values were changed to Table 5-4 under Option 1-0 for Unrestrained
		Trip.
	N, 09/00	Corrected Table 1-3 to show power supply ranges.
		Changed instruction manual front cover, Figures 4-1, 4-3, and 4-5 to
		show new unit case covers.
		Changed Figure 4-32 per markup.

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Manual		Change
Revision and Date
M, 04/99		Table 3-1 changed mid range nominal volt 125 Vac to 120 Vac.
	Corrected Figures 4-24, 4-31a, and A-3
	Corrected page 4-38, Step 10; added note to page 4-39, Step 13, and
		corrected Steps 14 and 16.
	Page A-2, changed 3-Phase fault ratio current to 3-phase fault
		current.
	Page A-3, corrected formulas for Figure A-3.
	Under Section 4, Procedure One, Verify CT Performance, changed
		the procedure to the ANSI accuracy class method. This forced
		changes in the following steps: 12, 13, 14, 16, 18, 20, and 21.
	Under Section 4, Procedure Two, Verify CT Performance, changed
		the procedure to the ANSI accuracy class method. This forced
		changes in the following steps: 12, 13, 14, and 16.
	Added ECO revision information to Table 8-1.
	Added Setting Note 7 (ANSI Accuracy Class Method) to Appendix A.
L, 05/97		To delete the part number from the front cover of the manual.
K, 03/97		Deleted all references to Service Manual 9171300620.
	Changed the Title of Section 2 from “Controls and Indicators” to
		“Human-Machine Interface”.
	Replaced the Power Supply Options paragraphs with a new Power
		Supply paragraph explaining the new power supply design.
	Deleted Figure 3-2 and added Table 3-1, Wide Range Power Supply
		Voltage Ranges.
	Changed Power Supply Status Output for Type G power supply on
		the formerly page 3-6 (now page 3-4) from terminals 9 and 20 to
		terminals 9 and 19.
	Added information to Section 4 to help the user understand the
		procedures better.
	Deleted all NOTES FOR USERS OF SENSING INPUT TYPE F
		RELAYS and added Section 7, Difference Data.
	Changed previous Section 7, Manual Change Information, to Section
		8.
	Added an Appendix A to clarify the setting procedures.
	Added an index to help the user find information easier.
	Changed the format of the manual.
J, 01/96		Deleted “Difference Data” (formerly Section 7) and included notes for
		users of Type F relays.
	Moved all information regarding relay settings and checking relay
		setting from Section 5, Testing and Setting, to Section 4, Installation.
		Section 5 now contains information on test procedures.
	Combined 50 and 60 Hz Verification Tests.
		Various editorial changes.
	Reformatted instruction manual as Windows Help file for electronic
		documentation.

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Manual		Change
Revision and Date
I, 01/95		Added outline (box) to Figure 5-8 to highlight the figure.
	Page 5-42, Step 5, changed, “should be less than 4.45” to, “must be
		less than 4.45”.
	Added note to page 5-43, Step 10 and corrected the formula in Step
		10.
	Page 5-45, Step 18, corrected formula and high side results; and
		Step 19, changed last sentence from H (13 x tap) to S (21 x tap).
	Page 5-46, Steps 20 and 21, corrected figure references.
H, 12/94		Page 1-6, changed Specification for Restrained Output, Pickup
		Accuracy.
	Changed Section 5, Testing and Setting, Verification Tests (all
		models): Steps 1, 4, 5, and 8; and Table 5-4.
	Page 5-50, Jumper Positions Wye-Delta 1, Step 3: Corrected Input 2
		terminal identifications.
	Page 5-51, Jumper Positions Delta2-Delta2, Step 2: Corrected
		verification statement.
G, 09/94		Changed all sections to reflect new Option 1-1.
	Added to Section 5 four examples for testing relays to clarify test
		procedures.
	Added to Section 5 one procedure for setting relays.
	Corrected typographical and illustration errors.
F, 03/93		Changed formula pages 5-4, 5-10, 5-16, and 5-22 from I = the square
		root of K over t, to I = K over the square root of t.
E, 01/93		Manual was revised to incorporate a revision in the relay that made
		sensing input type F obsolete and included the 1 A, 60 hertz and 5 A,
		50 hertz model relays.
	Section 5, Test Setup, diagrams were changed to clarify relay
		connections.
	Added three relay Internal Connection diagrams.
	Changed unrestrained maximum time to trip, reference old Tables 5-4
		and 5-8 (new Tables 5-4, 5-8, 5-12, and 5-16).
	Renamed Section 7, Manual Change Information to Section 8,
		Manual Change Information and added new Section 7, Difference
		Data to support BE1-87T relays with Sensing Input Type F.
D, 06/92		Manual was revised to include the 1 A, 50 Hz model relay and
		reformatted to a new Instruction Manual style.
	Additional connection diagrams were included in Section 4 and test
		plug information was added to Section 6.
	Minor typographical errors were also corrected.
C, 03/91		Table 5-1 was expanded and Figure 5-4 Test Setup illustration was
		added.
		Miscellaneous editing.
B, 03/91		Manual (with the exception of Section 2) was rewritten for ease of
		use.
A, 06/90		Figure 3-1 (Functional Block Diagram) corrected.
	Formula in caution note (formerly on p. 4-17, now on p. 5-2)
		corrected.
		Miscellaneous editing.

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CONTENTS

SECTION 1 • GENERAL INFORMATION ................................................................................................		1-1
SECTION 2 • CONTROLS AND INDICATORS........................................................................................		2-1
SECTION 3	• FUNCTIONAL DESCRIPTION ...........................................................................................	3-1
SECTION 4	• INSTALLATION ..................................................................................................................	4-1
SECTION 5	• TEST PROCEDURES ........................................................................................................	5-1
SECTION 6	• DIFFERENCE DATA ..........................................................................................................	6-1
APPENDIX A • SETTING NOTES ............................................................................................................		A-1

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SECTION 1 • GENERAL INFORMATION

TABLE OF CONTENTS

SECTION 1 • GENERAL INFORMATION ................................................................................................	1-1
Introduction ............................................................................................................................................	1-1
Description .............................................................................................................................................	1-1
Application..............................................................................................................................................	1-2
Single-Phase ......................................................................................................................................	1-2
Three-Phase.......................................................................................................................................	1-2
Percentage Restraint..........................................................................................................................	1-2
Second-Harmonic Restraint ...............................................................................................................	1-2
Fifth-Harmonic Restraint ....................................................................................................................	1-3
Unrestrained Trip................................................................................................................................	1-3
Options...................................................................................................................................................	1-3
Push-To-Energize Output Pushbuttons .............................................................................................	1-3
Auxiliary Output Contacts...................................................................................................................	1-3
Power Supply .....................................................................................................................................	1-3
Model and Style Number .......................................................................................................................	1-4
Style Number Example.......................................................................................................................	1-4
Specifications .........................................................................................................................................	1-5

Figures

Figure 1-1.	Style Number Identification Chart ...........................................................................................	1-4
Figure 1-2.	Percentage Restraint Characteristic .......................................................................................	1-6
Figure 1-3. Unrestrained Response Times and Restrained Response Times..........................................		1-8

Tables

Table 1-1.	Multiples of Tap ........................................................................................................................	1-6
Table 1-2.	Harmonic Attenuation...............................................................................................................	1-7
Table 1-3.	Power Supply Specifications....................................................................................................	1-9

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SECTION 1 • GENERAL INFORMATION

Introduction

These instructions provide information concerning the operation and installation of BE1-87T Transformer Differential Relays. To accomplish this, the following is provided:

•Specifications

•Functional characteristics

•Mounting information

•Setting procedures and examples

WARNING!

To avoid personal injury or equipment damage, only qualified personnel should perform the procedures presented in these instructions.

These instructions may be used in place of all earlier editions. For change information, see Section 8.

Description

BE1-87T Transformer Differential Relays provide primary protection for power transformers and are available in either Single-Phase or Three-Phase configurations. The solid-state BE1-87T compares the currents entering and leaving the protected transformer. If a fault is detected, the relay initiates a trip signal to isolate the power transformer. This limits damage to the transformer and minimizes the impact on the power system.

BE1-87T relays use three types of restraint:

NOTE FOR USERS OF SENSING INPUT TYPE F RELAYS

Users of BE1-87T relays with Sensing Input Type F (three-phases three inputs per phase) will find Difference Data in Section 6 of this manual that describes features specific to these relays. The three-phase, three inputs per phase design, previously available as Sensing Input Type F, has been modified and is now available as Sensing Input Type G. Due to differences in components and output terminal connections, Type G relays are not compatible with earlier versions of the BE1-87T with Sensing Input Type F. There are also differences in the output connections as described in Section 6, Difference Data.

•Percentage of through-current

•Second harmonic

•Fifth harmonic

Selectivity in differential relaying is based on the ability to distinguish between internal and external faults. This is achieved by comparing the currents into and out of a power transformer. Comparing these currents often requires more than two inputs. For example:

•Power transformers may have a significant portion (greater than 10%) of the current flowing in a third or tertiary winding.

•Power transformers can have multiple breakers for a given winding (e.g., ring bus or breaker-and- a-half bus).

BE1-87T relays are available with up to five restraint inputs for the single-phase unit and up to three restraint inputs per phase for the three-phase unit.

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Application

In general, power transformers have different values of current flowing through their primary, secondary, and tertiary windings. These currents have specific phase relationships depending upon the connections of the individual windings (e.g., wye/delta). As inputs to a differential relay, these currents must be compensated or scaled so that the relay can compare the inputs and determine when an unbalance exists. Under ideal operating conditions, the scaled vector sum of these currents is zero.

Because it is practically impossible to match the magnitudes of these detected currents from the various power windings using standard CT ratios, the currents are matched within the relay by scaling each of the applied currents by an appropriate factor called a Tap Setting. This is set by means of the front panel INPUT dials. By selecting suitable tap ratios, the applied currents are scaled within the relay to achieve the desired balance for normal operating conditions. BE1-87T relays offer a range of available tap settings for inputs between 0.4 A to 1.78 A (Sensing Input Range Options 2 and 4 for a 1 A CT) or 2.0 to 8.9 A (Sensing Input Range Options 1 and 3 for a 5 A CT). These settings are independently adjustable in increments of 0.02 A for Sensing Input Range Options 2 and 4, or 0.1 A for Sensing Input Range Options 1 and 3. These small increments allow more precise scaling of the applied currents and usually eliminate the need for installing auxiliary ratio-matching CTs.

Single-Phase

BE1-87T Single-Phase relays require phase angle compensation to be accomplished externally by proper connection of the system CT secondaries. A wye/delta transformer requires that the CT secondaries be connected in delta for the wye winding and in wye for the delta winding. This type of connection also eliminates the zero-sequence component of current which could cause a false trip (operation) during external ground fault conditions on the wye system.

Three-Phase

BE1-87T Three-Phase relays can provide zero-sequence filtering and compensation for phase shifts introduced by the connections of the power transformer. This 30° Phase Shift compensation (either ±30° or no compensation) is field selectable. Additionally, this feature allows sharing the transformer differential relay CTs with other relays or instrumentation.

BE1-87T relays use the highest input current (in per unit values) to operate on maximum restraint. The relay does not have a conventional operate winding in the internal magnetics. Operating current is developed within the electronics of the relay.

Percentage Restraint

A primary concern in differential relay applications is security against high current levels caused by faults outside the protected zone. Inevitable differences in the saturation characteristics between current transformers require a compensating decrease in relay sensitivity. It is also necessary to be able to adjust the sensitivity to compensate for transformer voltage taps or CT mismatches. This is accomplished by providing a restraint factor proportional to the current flowing through the protected zone (throughcurrent).

BE1-87T relays maintain sensitivity at a specified ratio of trip current to through current. This ratio, generally referred to as slope, is front-panel adjustable in 5% increments from 15 to 60%.

Second-Harmonic Restraint

Magnetizing inrush current presents another problem unique to transformer differential relays. Relays must be capable of detecting the small differences in current caused by the shorting of a limited number of turns, yet remain secure against the occurrence of magnetizing currents many times the transformer rating (as seen at one set of terminals).

Although magnetizing inrush is usually associated with the energizing of the transformer, any abrupt change in the energizing voltage may produce this phenomenon. Common causes are the transients generated during the onset, evolution, and removal of external faults. Desensitizing the relay only during energization is therefore insufficient.

Magnetizing inrush produces an offset sine wave rich in all harmonics. BE1-87T relays use the second harmonic to restrain operation because it predominates and because it does not occur in significant magnitude or duration at other times.

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Three-phase BE1-87T relays use second-harmonic sharing. The second-harmonic content of all three phases is summed together to derive the restraint for each phase. As a result, the second-harmonic inhibit range and the associated factory setting, is higher than on single-phase relays.

Fifth-Harmonic Restraint

Power transformer overexcitation causes additional exciting current to flow into one set of terminals. This presents an apparent differential (or operating) current not attributable to an internal fault. Although potentially damaging, overexcitation is not an internal fault and, therefore, is not an appropriate condition for transformer differential relay operation. One of the principal components in the complex waveform produced during overexcitation is the fifth harmonic. BE1-87T relays use fifth-harmonic restraint to inhibit the differential relay operation.

Unrestrained Trip

Severe internal transformer faults may cause CT saturation. Under such circumstances, harmonicrestraint transformer differential relays may fail to trip because of the extremely high harmonic content in the waveform. Lack of operation can result in severe transformer damage.

BE1-87T relays provide an independent unrestrained tripping function. When set above the possible inrush current magnitude, this function provides high-speed protection for the most severe internal faults.

Options

Push-To-Energize Output Pushbuttons

Two PUSH-TO-ENERGIZE OUTPUT switches are available as a means to verify external output wiring without the inconvenience of having to test the entire relay. Option 2-S provides a small pushbutton switch for each isolated output function (Restrained and Unrestrained) and may be actuated by inserting a thin, non-conducting rod through access holes in the front panel. Refer to Figures 2-1 through 2-4 for location.

Appropriate power must be applied to Power Supply terminals 3 and 4 (shown in Figures 4-7 through 4- 10) for these pushbuttons to operate the output relays. However, it is not necessary to apply currents to the sensing inputs of the relay for these switches to function.

Auxiliary Output Contacts

Three types of auxiliary output contacts are available: Normally open, normally closed and SPDT. The contacts can be made to respond to a restrained trip, an unrestrained trip, or both. Refer to the Functional Description: Auxiliary Relay Option for further information.

Power Supply

Various power supply options are available to allow the BE1-87T to be used with standard supply voltages. See the Style Number Identification Chart, Figure 1-1, for details.

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Model and Style Number

The electrical characteristics and operational features of the BE1-87T Transformer Differential Relay are defined by a combination of letters and numbers that make up its Style Number. The Model Number together with the Style Number, describe the options included in a specific device and appear on the front panel, drawout cradle and inside the case assembly.

Upon receipt of a relay, be sure to check the Style Number against the requisition and the packing list to ensure that they agree.

Style Number Example

The Style Number Identification Chart (Figure 1-1) defines the electrical characteristics and operational features included in BE1-87T relays. For example, if the Style Number were G1E-A1Y-D1S0F, the device would have the following:

BE1-87T Model Number (designates the relay as a Basler Electric, Class 100, Transformer Differential

Relay)

G

Three-phase sensing with three inputs per phase

1

2.0 to 8.9 A Sensing Range at 60 Hz

E

One unrestrained output contact and one restrained output contact

A1

No intentional delay in the outputs

Y

48/125 Vdc switchable

D

Current operated targets

1

Percent IOP display and high-speed trip

S

Push-to-Energize outputs

0

No auxiliary output

F

Semi-flush mounting

Figure 1-1. Style Number Identification Chart

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Specifications

The BE1-87T relay is available in either single-phase or three-phase configurations and with the following features and capabilities.

Current Sensing Inputs		The unit is designed to operate from the secondary of current
		transformers rated at either 1 A or 5 A. Frequency range is ±5 Hz of
		nominal.
Maximum Current Per Input
	1 Ampere CT Units	4 A continuous; 50 A or 50 X tap (whichever is less) for 1 second.
	5 Ampere CT Units	20 A continuous; 250 A or 50 X tap (whichever is less) for 1
		second.
		For ratings other than one second, the rating may be calculated as:
		I =	K
				t
		Where:
			t is the time (in seconds) that the current flows
			K = 50 A or 50 X tap, whichever is less (1 Amp CT Units), or
			K = 250 A or 50 X tap, whichever is less (5 Amp CT Models)
Current Sensing Burden		Less than 0.02 ohm per phase.
Tap Setting Control (Scaling)		Front panel rotary switches, labeled INPUT, permit scaling the
		sensed input current (or tap setting) over the range of:
1	Ampere CT Units	0.4 to 1.78 in 0.02 A increments.
5	Ampere CT Units	2.0 to 8.9 A, in 0.1 A increments.
Restrained Output
Pickup Range		Front panel thumbwheel switches adjust pickup of the restrained
		output as a percentage of the through current. The range is 15 to
		60% of the operating current in 5% increments.
Pickup Accuracy		±6% of pickup ±100 mA (5 Ampere Units) or ±20 mA (1 Ampere
		units).
Minimum Pickup		0.35 ±6% of tap setting. Refer to Table 1-1 and Figure 1-2. Table 1-1
		provides calculated intersection points of the slope characteristic
		and the minimum pickup (in multiples of tap) as shown in Figure
		1-2. The calculation was derived from the formula:
			Maximum IRestraint			= Minimum Pickup
							Percent of Slope
		For example:
			Minimum Pickup =				0.35	=1.75
				Percent of Slope		20 %

The relay operates when the per unit difference current (operating current) is above the 0.35 pu or the slope line in Figure 1-2. Calculation examples are found in Section 5.

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Table 1-1. Multiples of Tap

Front Panel Setting %								15				20								25								30												35										40														45												50																			55									60
Maximum Restraint								2.33				1.75								1.40								1.17												1.00										0.875														0.778												0.700																			0.636									0.583
Current At Minimum
Pickup In Multiples of
Tap

Figure 1-2. Percentage Restraint Characteristic

Second-Harmonic Restraint	Inhibit of the restrained output occurs when the second-
	harmonic component exceeds a pickup setting which is 12%
	of the operating current for single-phase units or 18% for
	three-phase units.
Fifth-Harmonic Restraint	Inhibit of the restrained output occurs when the fifth-harmonic
	component exceeds a pickup setting which is 35% of the
	operating current.
Unrestrained Output
Pickup Range	Front panel thumbwheel switches adjust the pickup point of
	the unrestrained output over a range of 6 to 21 times the tap
	setting in increments of 1 x Tap.
Pickup Accuracy	±3% of the front panel setting.

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Outputs		Output contacts are rated as follows.
Resistive
120/240 Vac		Make 30 A for 0.2 seconds, carry 7 A continuously and break
		7 A.
250 Vdc		Make and carry 30 A for 0.2 seconds, carry 7 A continuously
		and break 0.3 A.
500 Vdc		Make and carry 15 A for 0.2 seconds, carry 7 A continuously
		and break 0.1 A.
Inductive
120/240 Vac, 125/250 Vdc		Make and carry 30 A for 0.2 seconds, carry 7 A continuously
		and break 0.3 A, (L/R = 0.04).
Target Indicators		Target indicators may be either internally-operated or current-
		operated (operated by a minimum of 0.2 A through the output
		trip circuit). When the target is current-operated, the
		associated output circuit must be limited to 30 A for 0.2
		seconds, 7 A for 2 minutes and 3 A continuously.
Single-Phase Units		Either an internally-operated or a current-operated target is
		supplied (as selected by the Style Number) for each trip
		output (i.e., the restrained and the unrestrained functions).
Three-Phase Units		Either internally operated or current operated targets (as
		selected) indicate the function (restrained or unrestrained)
		that caused the trip, and the tripped phase (A, B, C).
Harmonic Attenuation		Refer to Table 1-2.
		Table 1-2. Harmonic Attenuation
	Parameter	Minimum Attenuation at Indicated Fundamental
	(50 Or 60 Hz Models)	50/60 Hz	100/120 Hz	150/180 Hz	250/300 Hz		500 Hz
	Through Current	0	0	0	0		12 dB
	Operating Current	0	0	0	0		12 dB
	2nd Harmonic Restraint	12 dB	0	12 dB	12 dB		12 dB
	5th Harmonic Restraint	12 dB	12 dB	12 dB	0		12 dB

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Timing

Refer to Figure 1-3 for Unrestrained Response Times and

(For 60 Hz units only)

Restrained Response Times.

Figure 1-3. Unrestrained Response Times and Restrained Response Times

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	Isolation	In accordance with IEC 255-5 and ANSI/IEEE C37.90-1989,
		one minute dielectric (high potential) tests, as follows:
		All circuits to ground: 2,121 Vdc
		Input to output circuits: 1,500 Vac or 2,121 Vdc
	Power Supply	Refer to Table 1-3.
		Table 1-3. Power Supply Ratings
	Type	Nominal	Input Voltage Range	Burden at
		Input Voltage		Nominal
	K (midrange)	48 Vdc	24 to 150 Vdc	9.0 W
	J (midrange)	125 Vdc	24 to 150 Vdc	9.0 W
		120 Vac	90 to 132 Vac	21.0 VA
	L (low range)	24 Vdc	12 to 32 Vdc *	9.0 W
	Y (midrange)	48 Vdc	24 to 150 Vdc	8.5 W
		125 Vdc	24 to 150 Vdc	9.0 W
	Z (high range)	250 Vdc	68 to 280 Vdc	9.5 W
		240 Vac	90 to 270 Vac	28.0 VA

* Type L power supply initially requires 14 Vdc to begin operating. Once operating, the input voltage may be reduced to 12 Vdc and operation will continue.

Surge Withstand Capability	Qualified to ANSI/IEEE C37.90.1-1989, Standard Surge
	Withstand Capability (SWC) Tests for Protective Relays and
	Relay Systems, and IEC 255-5 Impulse Test and Dielectric
	Test.
Radio Frequency Interference	Maintains proper operation when tested in accordance with
(RFI)	IEEE C37.90.2-1987, Trial-Use Standard Withstand
	Capability of Relay Systems to Radiated Electromagnetic
	Interference from Transceivers.
UL Recognition	UL Recognized per Standard 508, UL File No. E97033. Note:
	Output contacts are not UL Recognized for voltages greater
	than 250 V.
GOST-R Certification	GOST-R certified per the relevant standards of Gosstandart
	of Russia.
Patent	Patented in U.S., 1991, U.S. Patent No. 5014153.
	Patented in Canada, 1993.
Shock	In standard tests, the relay has withstood 15 g in each of
	three mutually perpendicular axes without structural damage
	or degradation of performance.
Vibration	In standard tests, the relay has withstood 2 g in each of three
	mutually perpendicular axes swept over the range of 10 to
	500 Hz for a total of six sweeps, 15 minutes each sweep,
	without structural damage or degradation of performance.
Operating Temperature	–40°C (–40°F) to 70°C (158°F)
Storage Temperature	–65°C (–85°F) to 100°C (212°F)

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Weight	22.3 lbs (10.1 kg) maximum (three-phase unit)
	19.5 lbs (8.85 kg) maximum (single-phase unit)
Case Size	All units are supplied in an M1 case size. See Section 4,
	Installation for case dimensions.

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BE1-87T General Information

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SECTION 2 • CONTROLS AND INDICATORS

TABLE OF CONTENTS

SECTION 2 • CONTROLS AND INDICATORS ........................................................................................	2-1
Location of Controls and Indicators .......................................................................................................	2-1

Figures

Figure 2-1. Sensing Input Range 1 or 3 Three-Phase, Three Inputs ........................................................		2-4
Figure 2-2.	Sensing Input Range 1 or 3, Single-Phase, Five Inputs .........................................................	2-5
Figure 2-3.	Sensing Input Range 2 or 4, Three-Phase, Two Inputs..........................................................	2-6
Figure 2-4. Controls Mounted Inside the Relay.........................................................................................		2-7
Figure 2-5.	Sensing Input Range 2 or 4, Option 1-1, Single-Phase, Five Inputs, % OF TRIP Option......	2-8

Tables

Table 2-1. Controls and Indicators ............................................................................................................

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ii		BE1-87T Controls and Indicators	9171300990 Rev V

SECTION 2 • CONTROLS AND INDICATORS

Location of Controls and Indicators

Table 2-1 lists and briefly describes the operator controls and indicators of the BE1-87T Transformer Differential Relay. Reference the call-out letters A through M to Figures 2-1 to 2-3; N through Q to Figure 2-5. Exploded views of controls that are mounted inside the relay (call-out letters B, D and I) are shown in Figure 2-4.

Table 2-1. Controls and Indicators

Letter	Control or Indicator	Function
A	INPUT (or TAP) Switches	Front panel INPUT switches are used to scale the
		transformer currents. There are two of these rotary
		switches for each input.
	1 Ampere CT Units	Each of the upper switches is calibrated to represent
		the tenths and units digits (0.4 through 1.6) of tap
		value. Each of the lower switches is calibrated to
		represent two-hundredths of tap value for each
		increment. Always add the setting of the lower switch to
		that of the upper switch. For example, if a setting of
		1.02 is desired, the upper switch must be at 1.0 and the
		lower switch must be at 0.02. The total setting range for
		each input is 0.4 to 1.78.
	5 Ampere CT Units	Each of the upper switches is calibrated to represent
		the units digit (2 through 8) of tap value. Each of the
		lower switches is calibrated to represent tenths of tap
		value. Always add the setting of the lower switch to that
		of the upper switch. For example, if a setting of 5.0 is
		desired, the upper switch is set to 5.0, the lower switch
		must be at 0.0. The total setting range for each input is
		2.0 to 8.9.
B	30° Phase Shift Jumpers	These jumpers control the internal phase shift of the
	(three-phase units ONLY)	relay, either +30°, -30°, or 0°, depending upon the
		position of the jumpers provided for each input on the
		Analog #2 Board, shown in Figure 2-4. Additional
		information is in Section 4.
C	UNRESTRAINED PICKUP	This thumbwheel switch establishes the desired pickup
	LEVEL Switches	setting for all phases of the unrestrained output. The
		adjustment range is from 6 to 21 times the phase tap
		setting, in increments of 1.
D	CALIBRATE Switch	A two-position switch is located on each Analog #1
	(three-phase units ONLY)	Board and is easily accessible on the right side of the
		relay when it is withdrawn from the case. In the
		CALIBRATE position, these switches inhibit the
		harmonic share feature when calibrating the 2nd
		Harmonic Restraint. In the NORMAL position, the relay
		will operate normally.
E	POWER Indicator	This LED will illuminate when operating power is
		supplied to the internal circuitry of the relay.

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Letter	Control or Indicator	Function
F	PUSH-TO-ENERGIZE	Two momentary pushbutton switches are accessible by
	OUTPUT Switches Option	inserting a 1/8 inch diameter non-conducting rod
		through access holes in the front panel. Switch R,
		when actuated, closes the Restrained Output Relay
		contacts. Switch U, when actuated, closes the
		Unrestrained Output Relay contact(s).
		NOTE
		The optional Auxiliary Relay contacts (Option 3-1, 3-2
		or 3-5) will also be operated by the PUSH-TO-
		ENERGIZE switches if enabled by the two internal
		Auxiliary Relay Control Switches. (Refer to LETTER I.)
G	FUNCTION Targets Option	Electronically-latched LED targets that indicate an
		unrestrained or restrained output has occurred.
H	Target Reset Switch	Resets the electronically-latched targets.
I	Auxiliary Relay Control	Two internal slide switches, S1 and S2, enable the
	Switches Option	optional Auxiliary Output Relay to close only when a
		restrained output occurs (S1 ON), only when an
		unrestrained output occurs (S2 ON), or to close when
		either output occurs (S1 and S2 ON).
		When shipped from the factory, the Auxiliary Relay will
		be configured with S1 and S2 ON.
		NOTE
		The switches are located on the mother board and are
		only accessible by withdrawing the relay case.
J	ELEMENT Targets Option	Electronically-latching LED targets indicate the phase
	(three-phase units ONLY)	that caused a trip operation.
K	RESTRAINED PICKUP	Thumb-wheel switches (one per phase element) are
	LEVEL Switches	used to adjust the desired percent of allowable
		through-current restraint from 15 to 60 % in 5 %
		increments. (Through-current is the greatest relative
		individual input current.)
		The through-current restraint characteristic is
		individually adjustable for phases A, B, and C.
		In a three-phase unit, all three switches are typically
		kept at identical settings.
L	UNREST. TRIP Indicator	Red LED lights when there is an unrestrained pickup.
M	REST. TRIP Indicator	Red LED lights when there is a restrained pickup.
N	M Indicator	Red LED lights when the % OF TRIP pushbutton P is
		pressed and the restraint current is below the slope
		characteristic kneepoint as defined in Table 1-1. That
		is, the relay will operate at minimum pickup (0.35 times
		tap).
O	S Indicator	Red LED lights when the % OF TRIP pushbutton P is
		pressed and the restraint current is above the slope
		characteristic kneepoint as defined in Table 1-1. That
		is, the relay will operate based on the restraint
		characteristic.
P	Percent of Trip Pushbutton	Pushbutton that is used to activate the % of TRIP
		LEDs.

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Letter	Control or Indicator			Function
Q	% OF TRIP Indicators Option	When the % OF TRIP pushbutton P is pushed, eight
		LEDs, shown in Figure 2-5, are used to indicate the
		approximate percentage of operating current to:
		Minimum pickup (LED M also lights); or
		Slope characteristic pickup (LED S also lights).
		The eight LEDs represent the following approximate
		percentages.
		1 LED:	3% (Yellow LED)
		2 LEDs:	7% (Yellow LED)
		3 LEDs:	11%	(Yellow LED)
		4 LEDs:	20%	(Red LED)
		5 LEDs:	40%	(Red LED)
		6 LEDs:	60%	(Red LED)
		7 LEDs:	80%	(Red LED)
		8 LEDs: 100% (Red LED)
		A bar chart above the LEDs shows the relative
		percentage of trip.

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Figure 2-1. Sensing Input Range 1 or 3 Three-Phase, Three Inputs

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Figure 2-2. Sensing Input Range 1 or 3, Single-Phase, Five Inputs

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Figure 2-3. Sensing Input Range 2 or 4, Three-Phase, Two Inputs

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