U-602613, Calcs for Functional Requirements for First & Second Level Undervoltage Relays at 4kV 1A1,1B1 & 1C1

Calcs for Functional Requirements for First & Second Level Undervoltage Relays at 4kV 1A1,1B1 & 1C1

ML20116C719
Person / Time
Site:	Clinton
Issue date:	06/25/1996
From:	Haumann A ILLINOIS POWER CO.
To:
Shared Package
ML20116C590	List: ML20116C587 U-602613, Calcs for Functional Requirements for First & Second Level Undervoltage Relays at 4kV 1A1,1B1 & 1C1
References
19-AN-19, 19-AN-19-R02, 19-AN-19-R2, U-602613, NUDOCS 9608010082
Download: ML20116C719 (17)

Text

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to U-602613 LS-94-013 Page1 of18 Qi l

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l 19-AN-19 l

"Cales For Functional Requirement L

For 1st & 2nd Level Undervoltage Relays At 4 kV 1 A1, IB1, & IC1" l

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i 9608010082 960801 PDR ADOCK 05000461 p

PDR

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CALCULATION COVER SHEET SHEET 1 OF

/7 TITLE /DESCRII' TION:

DEPT /DIV CALCULATION NO.

E/EPED 19 AN-19 l

CALCS FOR FUNCTIONAL REQUIREMENTS FOR

)

l 1st & 2nd LEVEL UNDERVOLTAGE RELAYS AT QUAUTY SYSTEM CODE TOPIC BLDO/ELEV/ AREA j

4kV 1 A1,181, & 1C1 RELATED (or NA)

(or NA) l (Q or N) l O

AP E90 N/A l

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APPROVALS - NAME/ SIGNATURE /DATE l

READY FOR INCORPORATION:

l CORP PREPARING REVISION VOLUME PREPARED BY Al Haumann THIS V.

YES d

NO N/A 2

C

$ 1m if (ld )H DATE SIGNATURE CONFIRMATION REQUIRED MICROFICHE ATTACHED:

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YES d

NO U YES CHECKED BY PR M VOL. INCORP. ASSGNMNT.

Engineering 1

DATE siaNAtuRE MOD.

AP-28 ECN CR l

i COMMENTS:

MWR l

W $g(,s REVIEWED BY THIS VOLUME IS TO MAKE MINOR EDITORIAL CHANGES WHICH kgJg 'io (D,+

s CLARIFY THE CALCULATION

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Page 3 of 18 REVISION HISTORY Page 2 l

i Dept./Div. E/EPED Calc. # lH:AN-19 Revision 2 Volume (if applicable)

C i

Objective: Ihe.Surpose of this volume Calculation is to make minor _aditorial changes to clarify _the_ calculation __

l sn_that.it is clearer _for_those_ reviewers and. auditors _who_are_not fam!!iar_with the degraded _ Voltage issuesllor_the_ set.pointanethodology 1

l Reason: Reviews.hyEuclear_Assassment_ indicated that_there were areas of the_calculatioIL1 hat _were unclear or required _Ininor_aditoriaLcorrections. This_yolume incorporates _theitcomments._No numericalnor_lechntcatchanges to volume Bare made by this volume.

List of Affected Pages: pages 5 through 8 of the base calculation. This.yolumaJiupersedes_vnlume_B

)

Revision Volume (if applicable) l l

Objective:

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l Reason:

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l List of Affected Pages:

Revision Volume (if applicable) l l

Objective:

l Reason:

List of Affected Pages:

i NF-303 (10/95)

Attachm nt 2 i

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TABLE OF CONTENTS PAGE COVER SHEET 1

REVISION HISTORY 2

TABLE OF CONTENTS 3

PURPOSE 4

DISCUSSION 4

INPUTS 5

ASSUMPTIONS 8

METHODOLOGY 8

EVALUATION 13 REFERENCE LIST 17 ATTACHMENTS

~ Attachment 1 Probability table 1page ABB instruction IB 7.4.1.7-7 issue D 12 pages ABB Descriptive Bulletin 41-233S September 2 pages 1990 ABB Type Test Certificate Number RC-6004 6 pages Revision 0 dated 2/10/89.

HP 3458A Multimeter Data Sheet dated May 7 pages 1991 & Test and Measurement Catalog 1994.

Copies of selected pages Westinghouse Electric Corporation Product 2 pages bulletin 44-215 D WE A dated July 15,1976 for type PCO-60 Voltage transformers i

1 i

Attachmsnt 2 to U-602613 LS-94-013 P g fgof 1g g7 4

CALCULATION 19-AN-19 REV. 2 VOL C

[DeptJDiv. E/EPED]

PURPOSE

'The purpose of this Calculation is To evaluate the use of an ABB 27N undervoltage relay in the Second Level Under-Voltage (also called degraded voltage) protection scheme.

Determine the relay trip (drop-out) and reset (pick-up) bands based on the loop accuracy methods described in CI-01.00 Instmment Set-point Calculation Methodology (Reference 10).

The analytical limits (AL) for the second level under-voltage relay pick-up are as follows:

1. The maximum pick-up voltage is equal the minimum 4KV ESF bus voltage under steady-state LOCA loading with the off-site voltage at the minimum expected

value,

2. The minimum pick-up voltage is equal to the minimum 4KV ESF bus voltage required to start and run the LOCA required equipment.

The allowable value (AV) will also be established by this volume and this number will be used in the Tech Spec revision which is being prepared to support the new relay settings.

DISCUSSION The second level under voltage relay scheme has a two fold function. It must ensure that there is adequate voltage following the LOCA block start initiation for the ESF required equipment to start and mn. It must also prevent the ESF buses from transferring to the on site source if there is adequate voltage from the o'f-site source to operate the ESF equipment. Therefore the second level under voltage relay pick-up voltage (accounting for the various instrumentation errors) must fall between these values.

In addition, we want to prevent spurious transferring of the ESF buses to the onsite source and allow for minor changes to the off site grid with out impacting the degraded voltage relay settings. We have therefore based on engineering judgment chosen (for LER avoidance) to limit the maximum relay pick-up to 0.75% below the 4160 volt bus 1 Al voltage found in Calculation 19-AQ-02 Rev. 3 attachment 10.2. This setting will provide a degree of margin below the minimum expected 4KV Bus voltage under steady state LOCA conditions with the 345 Kv switch-yard at the minimum expected value.

Calculation 19-AQ-02 Rev. 3 Attachment 10.2 lists the steady state minimum voltage at the Bus l Al as 3938 volts. 100%-0.75% of 3938 than equals 3908 volts. The minimum reset point will be the minimum voltage at the 4KV bus which will ensure that all the ESF equipment required for LOCA will start and run. The minimum voltage required by the ESF equipment will be taken from 19-AQ-02 Rev. 3 volume P Attachment 8.1 (3870 volts). The nominal second level under-voltage relay pick-up point has therefore been chosen to be mid way between the maximum and minimum reset-points or 3889. We will call this nominal value NTSP. This calculation will assure that there is adequate margin for NTSP between the maximum and minimum allowable values when the total relay loop error is considered.

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[DeptJDiv. E/EPED]

INPUTS 11.

The relays utilized in the Second Level Under-Voltage schen.e will be ABB type 2' N catalog number 41 IT6375-HF(or 410T6375-HF which has the same characteristics). The relay pickup range is from 70 to 120 volts, the dropout range is 70% to 99%, the pickup time delay is instantaneous. The drop out time delay will be set at minimum (= 0.1 sec) The relay requires a 125 volt nominal DC source to operate. The relay will include the harmonic distortion filter. The published relay tolerances from Reference 3,4 and 5 EXPRESSED AS A l

PERCENT OF SETTING are as follows:

a)

Pickup and dropout setting repeatability with respect to temperature with a constant control voltage and the relay operating in an environment where the ambient temperature could vary between +10 to +40 C is 0.4 %. W e' will call this 26 value ATE.

b)

Pickup and dropout setting repeatability at a constant temperature and constant control voltage is 0.1%. We will call this 2S value VA.

l c)

Pickup and dropout setting, repeatability over " allowable" de control power range is 10.1%. The allowable de control power range for a 125 volt nominal relay is 100 to 140 V DC. The Tech Spec. requires that when AC power is available to supply the battery charger the DC buses must l

operate between 121 and 139 volts. The published DC supply error is l

considered linear over the operating range per Reference 10, Engineering l

standard Cl 01.00. Therefore, the published error of+0.1% can be divided by 40 volt allowable range. In addition, data in the ABB type test Certificate Reference 5 shows that this is conservatL e. ~he variation then l

equals *0.0025%/ volt.

We will call this 26 error PSE ad consider it to l

be +0.045% for our operating range.

d)

The radiation and humidity effects are considered negligible because the relays are not subjected to an environment with humidity or radiation above normal atmospheric conditions.

e)

The 27N relay has been subjected to 6g ZPA either axis biaxial broad band multifrequency vibration with out malfunction or damage per ANSI /IEE C37.98 (reference 4). Therefore there is no seismic impact to the relay accuracy.

f)

ABB tests indicate that there is no RFI interference effect associated with the relay. Therefore it is not considered a factor in this calculation (Reference 5).

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CALCULATION 19-AN-19 REV. 2 VOL C

[ Dept./Div. E/EPEDj.

I2.

The relay calibration setup will consist of a low noise variable AC power supply, the ABB 27N relay and a Hewlett Packard Model HP3458A Digital Multimeter.

HP3458A

\\

Varable AC Multimeter 3

Power supply e

ABB 27 N Relay Relay test set-up figure 1 The HP 3458A Specification and accuracy from Reference 6 are as follows:

a)

Minimum resolution at 100 volt range is 10 micro volts b)

The Accuracy coefficient in %/ degree C is 0.001% of reading plus 0.0001% of range (with the meter set on the 100V range). We will call this 36 value C1 ATE c)

The AC accuracy with the meter set on the 100 V range is (a 36 value) 0.02% of reading plus 0.004% of range and will be called C1 VA.

d)

The meter is calibrated using a 10 volt DC test cell traceable to US NIST with an added error of 2 ppm or 0.0002%. We will call this 36 value ClSTD.

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13 _

The detection loop consists of the 4KV bus which we wish to measure, a potential transformer (PT) to convert 4KV to 120 volts and the ABB 27N relay.

The pts for DIV. I & II are Westinghouse PC-60 and, for DIV. III, GE type JVM-3. Both PT models have a ratio of 4200 - 120 volts and are class lE. They conform to ANSI C57.13-1968 metering accuracy class for.03 class standard burdens W, X, M, & Y. The pts were purchased to Westinghouse drawing l

EN005, and GE data sheet 317A6131, and S&L form 1815-L (Reference 1). The i

PT burden was established using E02-1 AP12 SH I1 R/W, E02-1 AP99 SH 36 l

R/D, E02-1 AP99 SH 38 R/U E02-1 AP12 SH 13 R/V, E02-1 AP12 SH I5 R/T, and E02-lHP99 SH 107 R/L (Reference 7), and the load data from the vendor manuals (Reference 1). The PT burden consists of a CV2 relay, the 27N relay, a voltage transducer, a lamp and a voltmeter (Note: the EMTs shown on E02-1 AP12 SH 13 R/V are being disconnected from the pts by mods AP-027,28,

&29). The total burden on the PT is 7.5VA with a possible change in burden l

(caused by switching the voltmeter between phases) of 1 VA. From the j

performance curve found in reference 9, we can see that for a change in burden of 12.5 VA the turns ratio correction changes 0.1%. Therefore, if the actual change is i VA the change in PT turns ratio would be.008% of rating. The curve also shows that the PT ratio correction factor should be.997.

14.

Two relays will be installed in Div. I & II (one between phase AB and one between phase BC). The relay trip functions are wired in series so that both j

relays must trip in order for the protective action to be initiated. Only one relay l

must reset for the timer to reset, preventing transferring ofload to the diesel.

l Reference E02-1 AP12 sheets 11 & 13 (Reference 7).

15.

Two relays will replace the present single three phase relay in Div. III. The new single phase relays will monitor phase AB and BC. The trip contacts are wired in series. All the elements must sense a degraded voltage for the protective function l

to be initiated. Only one relay must reset for the timer to reset, preventing transferring ofload to the diesel. Reference E02-lHP99-sheets 107,103, & 102A l

(Reference 8).

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LS-94-013 Page 9 of 18 PAGE 8 of 17 CALCULATION 19-AN-19 REV. 2 VOL. C

[DeptJDiv. E/EPED]

ASSUMPTIONS i

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Al.

The accuracy's published by the instrument manufactures are considered as a 95% probability value, equal to two standard deviations (2a). This assumption does not require verification based on engineering judgment i

and direction given in Engineering Standard CI 01.00 Instrument Set-point Calculation Methodology (Reference 10).

A2 All accuracy data is considered to be a normal distribution.

l A3 The ABB 27N relay drift for 6 months is assumed to be equal to relay accuracy of l

.1%. For an 18 month suiveillance period the drift error (VD) is equal to the j

following:

r i

VD:=

E0.1 VD=0.1732 % Error 26 l

3 6 This assumption does not require verification based on engmeenng j

judgment and direction given in Engineering Standard CI 01.00 Instrument Set-point Calculation Methodology (Reference 10)

METHODOLOGY M. I.

The accuracy for the ABB27N relay (A27N) will be calculated by the square root l

of the sum of the squares method.

M.2 The nominal relay pick-up point will be calculated by taking the nominal relay l

pick-up voltage at the 4KV bus and reflecting it to the low voltage side of the PT Potential transformer primary ratio correction low side voltage voltage 3889 35 0.997 111.4486 Table 1 to U-602613 LS-94-013 Page 10 of 18 PAGE 9 of 17 CALCULATION 19-AN-19 REV. 2 VOL C

[DeptJDiv. E/EPED]

M3 The loop calibration error will be calculated as follows:

a) First the calibration instrument error Cl must be determined a.D The HP3485A accuracy error CIVA from the inputs above at 111 A4V can be is 111.44.0002 + 100 00004.100 = 0.0236% error 111.44 a.2) The temperature error contribution Cl ATE can be expressed as follows, noting that the Calibration lab temperature is kept at 72' F 2F or within 1.l*C. The temperature of the test instrument can be read directly by the HP3485A and the requirement that the test instrument be calibrated and used at 72* F

• 2'F will be controlled by the relay calibration procedure. From the input data for the temperature error would then be expressed as 1.1 "

-100 - 0.0012

% error

+

t11.44 a.3) The calibration instrument error Cl then becomes Cl :=dCIVA + C1 EAT 2

2 C1 =0.0236

% ERROR b) The next step is the calibration of the relay using the set-up shown above in figure 1. The calibration loop error (CL) is determined as follows:

b.1) Based on conversation with the Waterford plants, the ABB 27N relay can be set to a resolution of.005 volts AC. This will be considered the calibration resolution for the calibration. Therefore the resolution error R j

will be determined as follows:

R :=

-100-R = 0.0045

% ERROR 111.44

I to U-602613 LS-94-013 Page 11 of 18 PAGE 10 of 17 i

CALCULATION 19-AN-19 REV. 2 VOL. C (DeptJDiv. E/EPED]

b.2) The new ABB 27N relay calibration procedure will allow for an acceptance band of*0.04 volts. Therefore the calibration as-left tolerance error (ALT) will be determined as follows:

ALT :=

-100 ALT = 0.0359

% ERROR 111.44 b.3) The calibration instrument error Cl is taken from a) above b.4) the calibration loop error than becomes ff LT l' A I f1 8 fCI l' I

+ ! )l + l13 )

CL := 2 J I CL -0.0288

% ERROR ii 3 i i

This is considered to be 25 c) The next step is to determine the channel instrument accuracy (AI). This will take into consideration the various errors associated with operating temperature, DC voltage etc. From the inputs section above the errors are restated and the instrument accuracy determined:

VA :=.1 ATE := A PSE :=.045

% VD =0.1732 ff I A! := 2. j

VA *

+ lATE 3 2i 2 ;l +.

l + 1 l

f IPSE)2 IVD3 2 AI -0 4495 (i 2;

'l 2;

'2; i

This is considered to be 25 I

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Page 12 of 18 PAGE 11 of 17 CALCULATION 19-AN-19 REV. 2 VOL C

[DeptJDiv. E/EPED]

l, d) The loop accuracy AL can now be determined the inputs are as follows:

d.1) From b) above the calibration loop error CL =.028 %

d.2) From c) above the channel instrument error AI =.4495 %

d.3) From Input I3 above the PT error or EPT==.008%

fI 13:

2

I

+{

l + : EPfl2 C

f AL := h 2 ;

AL = 0.2252 qi i j i2j This is a 16 value M.4 -Illinois Power uses the GE methodology (Engineering Standard CI 01.00 - Reference #

10) for determining critical set points based on instrument errors. This methodology is statistically based. The desired probability for relay actuation is 95% (per Reg. Guide 1.105 -Reference # 11). In order to determine the 95% probability of either 2 relays actuating together or 1 of 2 relays resetting, the table Attachment I was set up. The table was established by plotting the probability distribution that one relay would actuate assuming a normal distribution curve (see Assumption # A2). The equation for that plot was:

1 5

f(x) = Er

• e 2 The probability that two will actuate together was determined by multiplying the probability of each of them together and plotting that curve accordingly. In this case that meant squaring the probability of one relay (since the probability for both relays is the same). The point on the Table in attachment I which equaled.95 was then found. This came out to be 1.96.

To determine the same o multiplier for when only one of the two relays needed to change

~

state, the probability that the relays would fail to actuate was considered. To do this, I minus the probability squared was tabulated (attachment 1). From this table the value for 95% confidence was found. This corresponds to a value of.76.

1 Therefore, the 1.96 Sis to be used for a 95% probability that two relays will actuate together and 0.76 6 that at least one of the two will reset.

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Page 13 of 18 PAGE 12 of 17 CALCULATION 19-AN-19 REV. 2 VOL C

[ Dept./Div. E/EPED]

M.4a Two 27N relay contacts (in series) are required to initiate the time delay relay and 1

the subsequent protective action. We have, therefore, determined that for a 1.96 S deviation about the set point the relay loop will activate with 95% confidence level. We will call this Ado. It can be expressed as:

Ado := 1.96 AL Ado = 0.4415 % of setting M.4b Only one of the two 27N relay contacts (in series) are required to reset the time delay relay and subsequently prevent the buses from transferring to the diesels.

We have, therefore, determined that for a.76 6 deviation about the reset point the relay loop will activate with 95% confidence level. We will call this Apu. It can be expressed Apu :=.76. AL Apu = 0.1712 % ofsetting i

l M5 The loop Allowable error will be calculated as follows:

a) The calibration loop error will be the same as above ffALT32 y,2 f I CL := 2-

'l

+l l + l C1 :*

CL -0.0288

% ERROR L3J tj (3i This is considered to be 2S b) The next step is to determine the channel instrument allowable accuracy with out the drift error (AV). This will take into consideration the various errors associated with operating temperature, DC voltage etc. From the inputs section above the errors are restated and the instrument accuracy detennined:

VA :=.1 ATE =.4 PSE =.045 A

ATE.g AV = 0 4148 %

AV = 2

+

di 2/

( 2/

( 2/

l*

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CALCULATION 19-AN-19 REV. 2 VOL. C l_

[DeptJDiv. E/EPEDj This is considered to be 26 c) The loop allowable accuracy ALV can now be determined the inputs are as follows:

l d.1) From b) above the calibration loop error CL =.028 %

d.2) From c) above the channel instrument error AV =.4148 %

l d.3) From Input I3 above the PT error or EPT=.008%

2 ICL AV32 32 EPT ALV:=

l - + -

I+ -

ALV = 0.2379 3(2 2 3 2

3 This is a 16 value M.6 Using the same methodoligy as above (Engineering Standard CI 01.00 - Reference # 10) for determining critical set points based on instmment errors, the probability that at least one of the two relays will reset is 0.76 6.

We have, therefore, determined that for a.76 6 deviation about the reset point the relay loop will activate with 95% confidence level. We will call the allowable value AVpu. It can be expressed as AVpu :=.76 ALV AVpu =0.158 % of setting EVALUATION The results can now be represented by a graph similar to the following:

f l

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1 a

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[DeptJDiv. E/EPEDj minimum off-site REAY ERROR RICION relay pick-up setting RELAYIRROR RECION 3870 volts probability In other words we will show that by setting the degraded voltage relay pick-up at 3889 the totalloop error will not cause (with a 95% probability) the relay to pick up below 3870 nor above the minimum off-site voltage as seen by the 4KV ESF buses. This can be represented by the following expressions:

We will call the upper limit of the permissible relay pick-up settings PUU and the j

lower limit PUL. The calculation of these values is l

PUU := 3908-l 3908 A "l P

PUU =39013104 Volts at the 4 KVlevel i

100j PUU PUU120 :=

PUU120 = 111.8014 Volts at the 120Vlevel

(.997 35)

PUL := 3870 + 3270. ^E" PUL = 3876.6245 Volts at the 4 KVlevel 100 PUL120 :=

PUL120 = 111.094 Volts at the 120Vlevel

(.997 35) 4 PUU>3889)PUL 3901.3104 > 3889 > 3876.6245 4

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LS-94-013 Page 16 of 18 PAGE 15 of 17 CALCULATION 19-AN-19 REV. 2 VOL. C

[DeptJDiv. E/EPED)

The lower limit of the Degraded voltage relay is dependent on the minimum voltage required to keep ESF equipment running. From calculation 19-AQ-02 we can show that the ESF equipment will run at 3832 volts. We will call this limit l

DOL. There is no upper limit for the drop-out except the physical restraints of the l

relay which will allow it to pick up in the range described above. The drop out can be adjusted between 70% and 99 % of the pick-up. We want to provide the maximum voltage to our equipment and still keep the relay pick-up as described above. Therefore we have chosen to set the drop-out at 99% of the pick-up or 3850 volts.

DOL:=3832+ 3832 DOL = 3848.9166 Volts at the 4 KV level 100 l

DOL l,

DOL 120.=

DOL 120= 110.2999 Volts at the 120V level l

(.99735)

DOL > 3832 3850>3848.9166 > 3832 L

o l

We will call the upper lower limit of the allowable relay (Tech Spec) pick-up settings PULV. The calculation of these values is l

PULV:= 3870+ 3870AVpu PULV = 3876.1153 Volts at the 4 KVlevel 100 PULV l

PULV 120:

PULV 120= 111.0794 Volts at the 120Vlevel

(.99735)

The critical requirement, from a plant safety standpoint, is that all the equipment required l

to support the LOCA block start receive sufficient voltage to start and run.- Therefore the critical degraded voltage relay parameter is that the relay must reset at or above 3870

- volts. This is equivalent to the relay minimum reset accounting for the appropriate relay

. errors.

The following table listing settings and analytical limits will be used as inputs for a Tech Spec. change and the procedure for calibration of the relays. The voltage at the 120 volt

L level reflects the required voltage at the.4KV bus as scaled (transformed) by the Potential l

Transformer. The ratio of the 4KV voltage to the 120 volt level is 34.895:1. The Degraded Voltage relay senses and is calibrated for voltage at the 120 Volt level.

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^8 PAGE 16 of 17 CALCULATION 19-AN-19 REV. 2 VOL C IDeptJDiv. E/EPED]

The calibration limits are established by drawing E02-1 AP04 sheet 001 and in the CPS calibration procedure. They are used as inputs to this calculation. The calibration limits are 0.04 volts. They are taken from section M3b.2 and are added and subtracted from the relay set-point at the 120 volt level. The 4 KV level value is equal to the 120 volt value times the PT ratio (35*0.997).

mmmery of Emits PICK.UP DROP 0UT 4kVlevel 120v level 4kw level 120v level nominal setpoint 3889 111.45 3850 110.33 Mn PICK-UP Max PICK UP Min DROP 0UT Max DROP 4UT 4ky level 120v level 4kw level 120v level 4ky level 120v level 4kw level 120v level calilwetion hmits 3888 111.41 3890 111.48 3849 11029 3851 110.37 techspec limits 3876 111.08

(

The second level undervoltage relay minimum pick-up and minimum drop-out voltages, at l

4KV buses, which will be used by other calculations are 3870 volts and 3832 respectively.

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[ Dept./Div. E/EPED]

l Reference 1 Westinghouse drawing EN005-6A REV 5, and GE data sheet 317A6131 REV. 2. The PT were all purchased per S&L form 1815-L. These documents are found in the purchase specifications 1

and vendor manuals for K-2801 and K-2968.

. Reference 2 E02-1 AP12 sheets.ll R/W& 13 R/V.

Reference 3 ABB instruction IB 7.4.1.7-7 issue D

- Reference 4 ABB Descriptive Bulletin 41-233S September 1990 Reference 5 ABB Type Test Certificate Number RC-6004 Revision 0 dated j

2/10/89.

1 Reference 6 HP 3458A Multimeter Data Sheet dated May 1991 Reference 7 E02-1 AP12 SH I1 R/W, E02-1 AP99 SH 36 R/D, E02-1 AP99 SH 38 R/U E02-1 AP12 SH 13 R/V, E02-1 AP12 SH 15 R/T, and E02-1HP99 SH 107 R/L.

l Reference 8 E02-lHP99-SH 107R/L,103 R/H, & 102A R/H.

Reference 9 Westinghouse Electric Corporation Product bulletin 44-215 D WE A dated July 15,1976 for type PCO-60 Voltage transformers.

Reference 10 Engineering Standard CI 01.00 Instrument Setpoint Calculation Methodology REV 0 1

Reference 11 Reg. Guide 1.105 INSTRUMENT SETPOINTS REV.1.

l t

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