'. s ,,,.~' • • , 0 Commonwea1tAtison 'i . One First National --Chicago, Illinois

·0

• Address Reply to: Post Office Box 767 · , Chicago, Illinois 60690 . ·

Mr. Robert Gilbert, Project Manager Operating Reactor ~ u.s: Nuclear Regulatory Commission Washington, D.C. 20555

January 2; 1985

Subject.: Dresden Station Unit 2. Integrated Piant Safety Assessment SEP Topic III-10:1:A, Section 4:12.1 Thermal Overload Protection for Motor~ ·6f Motor Operated Valves NRC Docket No: 50~237 ·

Reference: s: Rybak letter to R: Gilbert dated Nov~mber 4, 1~83:

Dear Mr. Gilbert:

The referenc~d letter constitut~s our last submittal relating to the subject topic: As a result of the NRC Staff's review of that submittal, various questions were raised: The answers to these questions were discussed with.you, Mr. R. Scholl and others during a telecon on· October 11, 1984: Enclosur~ 1 of this letter contains those questions and answers:

During the telecon, qu~stion~ were raised concerning our method · for. sizing therm'al overloads and our service experience with overloads ·sized by our method: Enclosure 2 provid~s this information ~nd also gives an example calculation including the appropriate vendor selection charts.

If you .have any questions concerning this matter, please contact this office.

One (1) signed original and·forty (40) copies of this transmittal are entlosed for your use.

Sincerely, : . . ·-- ________ ___:,-.-.,--]

...1.----------- . 850102 l . . 850.11700480·5000237 .: .. ' .

. ·: PDR ADOCK . PDR . L___ . ·, -, f'. ___ . ____ -'--:-·.~~-----=-·=- _:-: =.·l .

l.....- ··--- ·-~· B.t;~~ Nuclear Licensing Adminstrator

lm

cc: NRC Resident Inspector -·Dresden

9568N

. . ( li e e

Enclosure Page 1

The fo_llowing is a list of the questions and answers discussed during the October 11th telecon.

Ql) What is the range of the temperature compensation for the overload relays?

Al) Per General Electric Publication GES-7201A the range of ambient temperature compensation for thermal overload relay CR124K is -300C to 800C (-220f to 1760f).

Q2) What are the ambient temperature conditions surrounding the motor control centers and switchgear where thermal overload relays are located?

A2) Motor control centers and switchgear have been reviewed as part of the Environmental Qualifi~ation Program consistent with the guidelines of I.E. Bulletin 79-0lB and the DOR Guidelines for Evaluating Environmental Qualification of Class lE Electrical Equipment. Motor control centers and switchgear are located within a mild environment which is defind as an area controlled to a maximum of 1200f.

Q3) Clarify the discrepancy betwe~n the discussion of item 2b on page 2 of the referenced letter, specifically the use of "most conservative value" and the times given in the procedure. (For a 300% load 8.5 to 18 seconds is below the lower limit for a CR124K and L overload relay.)

A3) Per General Electric P~blication GEH-2487C (copy attached) 8~5 sec and 18.0 sec are the band limits for a CR123L quick trip at 300% of normal heater rating current. If the relay does not trip faster than 8.5 sec at 300% of normal heater rating current the most conservative value is met for a CR123L quick trip heater~

Q 4 ) P r o v i d e t y p i c a 1 mo t o r a n d r e 1 a y p r o t e c t i o n c u r v e ·s f o r a m.o t o r operated valve.

A4) The relay protection curve is shown on General Electric Publication GEH-2487C (see p.3). An MOV motor characteristic curve is also attached (see p.4).

Q5) Item 26 of the referenced letter stated, "Thermal overload settings have been proven .through the course of time, and modified where necessary~" Justify this sentence.

A5) About 8 y~ars ago the thermal overload relays for all of the motor operated valve relays were.reviewed. Heaters were changed as a ~esu.lt of that effort. Since that time Dresden 2 has not experienced a single Moto~ Operated Valve failure attributed to an overload heater that was properl_y sized by our method.

.i !

Enclosure· 1 Page 2

Q6) Clarify th~ discrepancy between CR123K heaters and CR124 series in ·step 11 of DMP 7300-5?

A6) 'CR123K refers to a series of overload heaters. CR124 refers to a series of overload relays that incorporate the CR123K heaters. See G.E. Publication·G"EH-2487C attached.

Q7) Justify the use of a single point in determining th~ zero ~oint and slope in an instrument calibration.

Al) Since overload relays are expected to perform within a band instead of a precise time-current curve, testing at two points would still not necessarily establish a zero point and slope. 300% of normal heater rating current would generally be half-way between full-load current and locked rotor current. If the most conservative value is met at 300% it can be expected that at other values of current the most conservative tripping time will also be met: Experience has shown that single point testing is justified to adequately check the device with respect to its Time-Current Curves.

53580-3

'l

',

J

Enc l osur~ 1

P age 3

GEH-2487C

control

INSTRUCTION S CAUTION : Before installing in a Nuclear application, determine that the product is intended for such use.

CR124K and CR124L AC or DC ambient compensated thermal overload relays

GENERAL Ambient compensated overload relays incorporate a dial for :!:15%

field adjustment of tripping current and temperature compensating bimetals so that it is no longer necessary to change heaters to elim inate such problems as nuisance tripping.

The ultimate tripping current of installed relay heater can be ad ­justed :!:15% by using the adjustment dial. Turn dial counter clock­wise to reduce ultimate tripping current and clockwise to increase ultimate tripping current.

OPERATION The motor current is carr ied through a heater element of a re­

sistance material (See FIGURE 1). The overloaded motor increases the current through the heater and generates suff icient heat to deflect the bi metal strip. The def lected strip causes the relay con­tacts I normally connected in the control circuit of the magnetic sw itch with which the relay is used) to open with a snap action and thereby disconnect the motor from the line. Typical tripping and resetting curves for a relay are shown in FIGURE 2. (Compensating bimetals expand or contract with changes in ambient to keep trip­ping point constant.)

HEATER SELECTION The heaters are of the interchangeable type. A sufficient number

of sizes are available to permit selection of the proper heater for any value of motor full- load current within the range ind icated in the heater table.

The heaters provide approximately 115 to 125% protection. Heat­ers should not be selected for motor ratings in excess of the rating

TERV .AL

Q\'t:'_R_OAD E!.,ElAL

r.:::=---COMPENSATING

CONTROL TERMINALS

BIMETAL

SNAP-fCHIO CONTACTS

FIGURE 1-C R124 overload relay with cover removed.

of the controller with which the relay is used.

The heaters will ultimately trip the relay in a 40C ambient on a current which is the minimum value of motor full - load current listed in the table multiplied by 1.25.

APPLICATI ON AND INSTALLATION The relay, and the controller with which it is used, should be

protected from excessive currents that might result from short circuit by the use of fuses , the rating of which should not exceed a maximum fuse size and rating listed in the heater tab le. In place of fuses, other branch circuit protective devices can be used in ac­cordance with the National Electrical Code.

The relay contacts will carry ten amperes continuously and make momentarily 30 amperes, but should not be used to interupt cur­rents in excess of those listed below.

CONTACT RATINGS 1 NC contact and 1 NC of SPOT type

Continuous Make Recommended Max Interrupting Carry Amp Amp Capacity, Amp

AC or AC or DC Circuits AC Circuits

DC DC 125V 250V 115V 230V 460V 575V

10 30 0.35 0.17 3 1.5 0.75 0.6

NO contact is for 25 va carry, 250 va make.

7CC

bOC

so 0

• O'

JC '

10 c

10 0

<:R t 24 K, l , M, N & P

"fp•cal lripp1nq Ar'ld R1·u-;t t 1n9 Ch .. rac:te,,~ 1 1c~

A mb.en t CompenH1il'd o .... .io.,d Rday

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B 10 IS 20 2S 30 4' 0 bO 80 100 ISO 200 300

T1mf> In Second~

FIGUR E 2 -Typical tri pping and resett ing characteristics for CR 124K and L overload relay in 40 C ambient.

GENERAL . ELECTR J"

GEH -24878

' , The reiays are shipped from the factory arrang& hand reset Qut may Qe changed to automatic reset by moving the end of the reset spring from the front position to the rear position by lifting out spring, pushing reset, and re-engaging spring. The two positions are indicated in FIGURE 3.

CAUTION : Overload relays, when adjusted for automatic reset, should not be used with two- wire, maintained contact pilot devices such as pressure, float and limit switches, as inadvertent restartini of the motor may occur.

The relay shou ld be installed in the vertical position as shown in FIGURE 1 with the reset button at the bottom. Heaters for these relays are ordinarily shipped separately and should be mounted in accordance with the instructions on the heater carton.

Clamp-type terminals are provided for the heater circuit and are suitable for use with 118 or smaller wire on the size 1 relay and with 114 or smaller wire on t he size 2 relay. The insulation must be strip­ped from the end of the wire.

Adjustments should not be attempted on the relay other than that of changing heaters. The bimetal strip should not be tampered with under any circumstances. Replacement heaters should be or-dered by Catalog Number. '

HAND RESET

AUTOMATIC RESET

t.

FIGU RE 3- View of C Rl24 overload relay showing auto and hand reset position.

GENERAL ELECTR IC COMPANY GENERAL PURPOSE CONTROL DEPARTMENT Bloomington, Illinois 61701

8/79

Enclos ur e 1

STANDARD TRIP HEATERS -age 4

FOR CR124K FOR CR124L

MAX HEATER NO. MAX MAX HEATER NO.

MAX MOTOR CR l 2J

FUSE SIZE MOTOR CRI 2J

FUSE Sl7E AMPS RATING AMPS RATING

1.07 K 1.2JA 6 0&1 '-65 KS.27 A IS 2 1.19 K1.J5A 6 0 &1 S. IJ KS .82A 20 2

I.JI K l.50A 6 0&1 S.69 K6 . .C2A 20 2 L O Kl.6SA 6 O&I 6.J2 K7 . IJA 20 2

1.59 Kl.82A 6 0&1 6.99 K7 .91A 2S 2 1.77 K2 .00A 6 O&I 7.69 K8 .7SA 2S 2

1.98 K2.22A 6 0&1 8.J7 K9 .63A JO 2 2.21 K2 . .C9 A 10 O&I 9. IJ KIO.SB JO 2 2.•0 K2.77A 10 O&I 9.96 Kl l . .CB JO 2 2.62 KJ .OIA 10 O&I 10.8 Kl 2.S8 JS 2 2.B9 KJ.29A 10 O&I 11.7 KIJ .68 • O 2 J.17 KJ.62A 10 O& 1 12.9 Kl•.8B 40 2

3.49 KJ.98A IS O&I 1.4. I Kl6.JB 4S 2 J.82 K4.38A I S O&I IS.4 K17.8B so 2 4.21 K.C .79A IS O&I 16.9 Kl9 .4B 60 2

HS KS.27A IS 0&1 18.8 K21 .JB 60 2 S. IJ KS.82A 20 0&1 20.7 K2J .6B 70 2 S.69 K6 . .C 2A 20 0&1 22.9 K26 .0B 70 2

6.J2 K7 .1JA 20 0&1 2S.5 K2 8.8B 80 2 6.99 K7.91A 2S O&I 28.1 K32.08 90 2 7.69 K8.7SA 2S 0&1 30.9 KJS.28 100 2 8.37 K9.63A 30 O&I JJ.9 KJ8.7B 110 2 9.13 KIO.SB JO O&I J7.J K42.SB 12S 2 9.96 Kl l."'8 30 0&1 .Cl.I K46.8B 12S 2

10.8 Kl 2.SB JS 0&1 •S .O KS1.5B ISO 2 11.7 KIJ .68 40 O&I 12.9 K l.C.88 40 O&I 1 .. . 1 Kl6.38 4S O&I 15."' Kil .BS so 0&1 16.9 K19 . .CB 60 0&1

18.8 K21.JB 60 1 20.7 K23 .68 70 I 22.9 K26.0B 70 I 25.5 K28.8B 80 1 27.0 K32 .0B 90 I

QUICK TRIP HEATERS

FOR CR124K FOR CR124L

MAX HEATER NO. MAX FUSE MAX HEATER NO. MAX FUSE MOTOR AMPS CRl23 RATING MOTOR AMPS CRI 2J RA TI N G

I.SJ ll.7.CA 6 5 . .C3 l6 18A 20 1.68 Ll .93A 6 S.99 l 6 80A 20 1.8.C l2 . l IA 6 6.S9 l 7 50A 20 2.0J l2.32A 10 7.27 l8 25A 25 2.2S L2 .55A 10 7.99 L9 JOA 2S 2.47 l2.82A 10 8.87 LIO OB 30

2.7J l3 . IOA 10 9.76 l 11 18 30 3.0J l3.4JA 10 10.7 l l 2 28 JS J.JS l3.80A IS 11.6 Lil SB JS 3.69 l 4.20A IS 13.1 LI A 78 40 "4.07 l -' .63A IS l.C . .C Ll 6 SB 4S 448 l.5 . I OA IS IS.8 LIB IB so .C.93 l5 .61 A IS 17.5 l 19 98 60 5.43 l 6 . 18A 20 19.2 122.0B 60 S.99 l6.80A 20 21.1 l 2A 18 70 6.59 ll.SOA 20 23.3 126 SB 70 7.27 l8.2SA 2S 2S.7 129 JB 80 7.99 l 9 .10A 2S 28.0 l J2 2B 90

8.87 LIO.OB JO JI . I LJS lB 100 9 76 l I l.18 30 JJ.9 LJ9 OB 110

10.7 LI 2.2B 35 37 .0 l42 68 125 11.6 LIJ.SB JS 41.5 L"'6 "B 12S IJ.1 ll 4.78 40 <S.O LS2.0B 150 14.4 L16.5B 45

IS.B Ll 8. IB so 17.S Ll9.98 60 19.2 122.0B 60 21. 1 124. I B 70 23 J 126.SB 70 2S.7 129.JB 80

27.0 l32.2B 90

GENERAL. ELECTRIC Printed in U.S.A.

These instructions do not purport to cover all details or variations in equipment nor to provide for every possible contingency to be met in connec­tion with installation, operation or maintenance. Should further information be desired or should particular problems arise which are not covered sufficiently for the purchaser's purposes, the matter should be referred to the General Electric Company.

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Enclosure 1 e . Page 5· SK-58237-1.-, CLEVELAN:::>. ~:o "1~1 u.u. A-C MOTOR PERFORMANCE CURVES

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E/S 576781 ff<AME JA-215R ·"- . h. P. 709 t/~~;~·,: ~>tc~'t

ROTOR 4W.00-2-AY . DUTY 15 ?!1~1 0 RPM \390 ....,r; .i:un TEST S. O. 2Y-160789 PtiASE 3 . VOU'S 2.30f 60 TEST DATE 12-L.-63 TYPE/FOR~ ?/Y~ ~HPt_ 8. .L/10., 7

2 . RESISTANCE AT 2~.265 Oi.1.mS>ESIGlll 110. 2l.00 w'R - .391 Lt:.:'t., •. t' ,.., • . ..... • .. ., .

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CYCLES 60 CODE K TEMP •. RI Sf: 75°C

.HEMA DESl·Cill -ENCLOSURE TalP

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10 Scale B in Sece

f Note i ' For other voltage connection ·l 2800

l . ·t• .. 2L

·f .. 100 i.::.ot 2

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current will v;uy inversely .with the volt.ago.

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Enclosure 2 Page l

In order t6 verify that Criteria 2 of .Regulatory Guide 1~106 is being met, Mr~ Scholl requested a copy of the method used in sizing overload heaters at Dresden Station. As part of this enclosure you will find that method along with a sample calculation for your information.

High starting torque~ limited duty motors used in motor operated valves require special techniques in the selection of running overload protection. These motors cannot tolerate as much stall time as continuous-duty general purpose motors, and have a definite running time rating. In the case of the valve operator motors at Dresden Unit 2, the stall time is 8 seconds· fo~ a 5 minute duty motor~ 10 seconds for a 15 minute duty motor and 15 seconds for a 30 minute duty motor. Therefore, the criteria for selecting motor overload heater elements is to allow the valve operator to be stalled for at least the above stall time and to allow the motor to run at full load torque for at least the motor duty cycle time. The attached sizing method always selects a heater that either just meets the stall time and duty cycle limits~ or exceeds those limits. This will ensure that a heater will be selected that will allow the motor to perform its safety function at the sake of potentially damaging the motor~ We feel that this methodology is consistent with Regulatory Guide 1. 106 which ensures that the TOL device does not prevent the valve operator from performing its intended function. .Please note that since the TOL heaters were resized at Dresden - 2, approximately eight years ago, there has not been a sjngle valve operator failure due to improperly selected overload heaters.

It is important to note that the mechanical torque switch is the primary line of defense against motor running overloads causing permanent motor damage. The primary function of the TOL device in the starter is to protect the motor only during the period of time when the valve operator is attempting to unseat a torque seated valve. It is during that moment, wh~n the torque switch is bypassed to prevent erroneous operation during unseating, that the TOL is the only defense against motor damage which may occur if the valve is stuck in the seated position. Tripping the motor at or slightly above the stall time noted in the attached metho~ will prevent permanent motor damage from bccurring in such a situation.

Duty cycle protection is important onlY if a mechanical problem in the valve or operator allows the motor to run free without stroking the valve~ Most of the valve operators in safety-related service have stroke times in the area of 30 seconds, while their motor duty ratings are 15 minutes. It is obvious that there has to be something physically wrong with the operator that the motor· should run as long as its duty cycle. Duty cycle protection prevents burning out the motor which would

. increase the damage to an already defective valve operator.

The above discussion demonstrates that the atta~hed TOL heat~r sizing method is consistent with the intent of Regulatory Guide l~ 106 in that the TOL heaters are selected in such a way that they will not trip out a valve operator prior to .succesgfully completing its safety function~ namely opening or closing a valve~

5379D

TITLE:

·PURPOSE:

CRITERIA:

-DEFINITIONS:

,· , /

' ,.,

Enclosure 2 Page 2

Method for Sizing Motor Operated Valve Thermal

Overload Heaters - Dresden Station

Provide a procedure for determining the size of

overload relay heaters used to protect safety-

related motor operated valve motors.

Heater sizing shall be done with emphasis on the .

safety equipment fulfilling its function,

rather than on complete motor .protection.

Full load. current· - the current drawn from :~the

line when the motor is operating at full load

torque ~nd full load speed at rited frequency

and voltage.

Locked rotor current - steady state current

taken from the line with the rotor at standstill

(at rated voltage and frequency) •

Time-current curves - graphs which· show the

reiationship between motor cuh~ent and the· time

for trippihg for a particular overload relay.

Heater tables - tables showing all of the

heaters which can be used with a particular type

of overload relay and the maximum current each

heater size will carry without tripping.

.. ->-.-... -:....- "'

PROCEDURE: I

·.a_Enclosure 2 'W'Page 3 ·

Obtain the follo~ing information:

A• ·Locked~rotor curient0of~the·motor to be

protected.

B •. Full load current of the motor to be

· protected.

c.. Duty time of the motor.

D. Type of overload relay.

- · l~ time~current curve

... 2~ thermal.overload relay heater table

E. Stroking time.

II Locked.Rotor calculations

A. Multiply the locked rotor current by 100.

B •. Determine the -thermal time limit for

carrying locked rotor current.

1. 10 ~econds if the motor is a 15-minute

duty motor •.

2. 15 secori~s for a.30-minute duty motor.

c-··. ;'.3•:~:~.8 seconds for a 5-minU-t~e· duty motor.

C•< Using: the ··time-cur rent curves determine the

percent of heater rating current required to

· open the overload relay contacts in the

thermal time limit. Use .the curve showing

the maximum current.

D. Divide the number calculated in Step A by

the percentage determined in Step c.

'I: ___ ., ...

,.

..

II"I

Enclosure 2 e Page 4

E. Using the heater tables, ~elect a heater

with a rating just below the current

calculated in Step n.

Full Load Calculations

A. Determine the minimum running. time for the

motor at full load current.

1. 20 minutes for a 15-minute duty mo·tor.

2 •. 40 minutes for a 30-minute duty motor.

3. 7 minutes for a 5-minute duty motor.

B. Using the time~current trip curve, determine

the percent of heater rating current

required to t~ip the motor in the minimum

·. running time.

C. Di v.ide the full load current by t.he curr-ent

rating. of the heater selected in Sectio.n II

and multiply the result by 100.

1. If this percentage is less than the .. _.

percentage determined in Step B, the

heater size calculated in Section II can ·

be used.

2. If the percentage is more than the

per~entage determined in Step B, proceed

to Step n.

D. Select a heater with the next higher cuirent

·rating.

.....

EXAMPLE:

Enclosure 2 e Page 5

E. ·Divide the full load current by the current

rating of the heater selected in Step D and

multiply the result by 100.

1. If this percentage is less than the

percehtag~ determined in Step B, the

heater size selected in Step D can ·be

used.

2. If the percentage is more than the

perc~ntage determined in Step ~'

. continue to select a heater with the

next higher c~rrent ~ating until one is

found which will have a percentage of

heater rating current less than the

percentage. of heater rating current

required to trip the motor running

time.

Obtain Data

A. ,Locked rotor current - 14~

B. Full-load .. current - 18.4A

c. 15-minute duty motor

D. Overload relay is a General Electric type

CR124A

E. Stroking time - 25 seconds

.. ~ .......... -···- ·---···-·----·--. '· ;

,.

Eric·l-osure 2 e Page 6

Locked Rotor calculatioris

A. (Locked rotor current) x 100 = 143 x 1-00 =

14,300.

B. The motor is 15-minute .duty, therefore, the

maximum time for carrying locked rotor

current is 10 seconds.

c. From the .time-current curve for the G.E.

CR124A~ the m~ximum percentage 6f hea~er

rating· current required to·trip within 10

seconds is 900%.

D. 14~300A ~ 900% = 15.9 amps

E. According to the heater table, the heater

with a rating just lower than 15.9 amps is

Cl5.1B with a· rating of 14.6- amps.

Full Load Calculatibns

A. The motor is 15-minute duty, therefore, the

minimum time for carrying full load current

is 20 minutes.

B. From the time-current curve for the G.E.

c.

CR124A, the percentage of heater rating

current required to trip in 20 min~tes is

110%.

18.4 ~ 14.6 = 1.26 1.26 x 100 = 126%

126% > 110%, therefore, Cl5.1B cannot be

used.

.,. ..

Enclosure 2 .Page 7

D. According to the heater table, the heater

E.

with a rating just higher than 15.9 amps is

C16.3B with a rating of 16.1 amps.

18.4 ~ 16.1 = 1.14 1.14 x 100 = 114% •

114% ~ 110%,. therefoie Cl6.3B cannot be

used.

1. The next higher rating is Cl8.0B with a

rating of 17.9A

18.4 ~ 17.9 = 1.03 1.03 x 100 - 103% < 110%

therefore, Cl8.0B can be used.

'· -. . . GEH~-2!\41B.,

; .. RF.PAIR AND RrnEWAL PARTS ·

, The relays are accurately calibrated by means of soecialized eQuio· · .. ·. ment and _no .attempt should be made to reJdjust or repair the unit.

· Renewal parts are not available. In the event of damage to the relay complete replacement is necessary ;\ ..

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800

100·

. .. ~ . c: 600

~ :: :c - 500 ... ~ . i z

I' u 400

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: -i._.~3l?O I . t:._

I_ 200

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-...... 100

4 . 6 8 .10 __ ._ la 20 2; ao ~u 6U _ ~~- 1_00 _ lo~ 200 300 · For CR123Al &.- Bl Time In S<cond•

Typical tripping and restarting characteristics for CR 124Al & Bl .overload relays i~ _40° ambient.

. -··· .. .-•- ...

---~---

- . --·~-

·MAX. MOTOR _AMPS.

. -- . .• 33·.

.37

.41 .• 46 ·- .n .H .61 .67 .n

- .84 ... --- .94

~'." 1.03 . 1.14

l.30 1.42

-- 1.61 ' 1.72 ... .. t.93 .. -:-:-2.-10-. ... .. . . 2.34-_ .. --- . 2.64

2.86 3.13

. 3.32. ,3.68. 4-.08 ..

4:-61 . 5.21 5.62 6.12 6.83 7.70

.. 8.48 . 9.19

liO 9,92 l µ) · H. l

.. 12.2 13.S

. "14.6_ r r1i _:.tG;t ___ _,_,_;i11.9 __

19.3 20.6 22.6- -24.8 27.6 30.0

HEATER TABLE ··:.·. CR 124 Bl SIZE 2

Enclosure 2 ·-Page 8·

HEATER TABLE

CR124Al SIZE 0 AND I.. -HEATER NO. OLD NO. MAX. FUSE

CR123 810 RATING - -·· -- . .... --:.C0.3GA .228 3

C0.39A 224 3 C0.43A . 225 .3 C0.48A 230 3 CM4A 525 3 CO.GOA 2.H 3 CO.G6A 526 3 C0.71A 527 .3

_(:0.71lA 233 3 C0.87A '528 3

. ·.c0.97A 529 3 Cl.09A . 530 3 Cl.ISA Bl 3 Cl.3 lA 738 3 Cl.48A B2 .3

-·- Cl.63A . 53'3 6 ".:. -Cl.84A . . -534 6 -~:._Ct.96.L.:..:. 535 6

..

- c2.20.a; 536 -- 6 .. - C2.39A -· --- - 537 ..... 6

C2.68A BB 10 C3.01A 539 10

~ 540 10 541 10 c

C3.79A 542 10 · C4:t9A 543 u ~ 544 1:5

. C uA 545 20 C5.92A 546 20 CG.30A 547 20 C6.95A 548

.. -:_25 :·.· .. C7.78A 549 25 CS.6 7 A. · 550 30 C9.S5A 55( 30 ' . C10.4B ,.. ;;uc!;.;-553 30

Cll.3B- I'-'' 554 35 Cl2.5B 555 . .co Cl3. 7B ! . ~56 45 . r15.1B_~ 557 45

_ Cl6~~B.. 267 so _ -_c1s.os_ 256 .... 60

Cl9.88 558 60 C2l.48 559 70 C22.88 561J 70 c25.o_a- 561 80 C27.3B 562 90. C30.3B 261 90

MAX. HEATER NO. OLD NO. ~.AX. FUSE .. ~ .. - : MOTOR AMPS. "; .. .,_

6.63 7.59 8.39 9.20.

.. ,. · ... 9.93 ,. ·. 11.2

12.5 14.1

- 15.5 17.4 19.8 21.2

227 24.9 27.3 '29.7

.34.2 40.2 "6.3 50.0

GENERAL ELECTRIC cmAPANY GENrnAL PURPOSE CONTROL DEPARTMENT BLOOMINGTON, ILLINOIS 61701 l/71

'

CR 123

C6.95A C7.78A C8.67A C9.55A

CI0~4B Cll.38 C12.SB Cl3.7B

C15.1B ClG.3B Cl8.0B Cl9.8B

C21.4B C22.8B C25.0B C27.3B

C30.3B C33.0B C36.6B C40.0B

810 RATING .....

548 ·20 . 549 25 550 30 .551 30

553 30 554 35 555 40 5.56 40

557 50 .. 26'1 50 256 . . 60 ... .5.58_ 70

559 70 .560 80 561 80 562 100

261 110 262 125 266. 150 263 P5