Design Guide for Rural Substations

diseño y guia de subestaciones rurales

4. 9. Rupard, Paul, East Kentucky Power Co-op., Winchester, KY
10, Sloan, Gordon, Sulphur Springs Valley Electric Co-op, Willeox, Arizona, (Former Chairman)
11. Crouch, Jim, Fairfield Electric Co-op, Winnsboro, South Carolina, (Former Member)

12. Nelson, Stewart, Lower Colorado River Authority, Austin, TX, (Former Member)

13. Emerson, Charles, Trico Electric Co-op, Tucson, Arizona, (Former Member

4, Platz, Peter, Coast Electrie Power Association, Bay St. Louis, MS, (Former Member)

15. Optiz, Mike, Western Farmers Electric Co-op, Anadarko, OK, (Former Member)

16. Heflin, Jack, Western Farmers Electric Co-op, Anadarko, OK, (Former Member)

17. Souhrada, Dan, Hoosier Energy Rural Electric Co-op, Bloomington, IN, (Former Member)
18. Sears, Chuck, Lea County Electric Co-op, Inc. Lovington, NM, (Former Member)

19. Grey, Weldon, Concho Valley Electric Co-op, San Angelo, TX, (Former Member)

20. Pehosh, Mike, Ozarks Electric Co-op, Fayetteville, AR, (Former Member)

21. Dedman, Jim, NRECA, Arlington, VA, (Former Coordinator)

Our thanks and appreciation are also extended tothe following organizations and companies who have
provided photographs, tables, charts, and figures that are used inthe bulletin:

American National Standards Institute Kullman Electric
‘American Society of Civil Engineers Lapp Insulator Co.

American Society for Testing Materials MeGraw Hill, ne

Bitronics Mitsubishi

Cooper Power Systems National Electrical Manufacturers Association
GE-Hitachi HVB, Ine Nova Net, Inc.

Haefely Trench Pedersen Power Products

Hubbell Power Systems Siemens

International Conference of Building Officials Southern States, Inc.

Insulated Cable Engineers Association, Inc. TM Sales, Inc

Institute of Electrical and Electronics Engineers Yokogawa

Keamey

RUS extends special thanks to Bil Kahanck, Lower Colorado River Authority, Austin, Texas, Chair of

the

IRECA T&D Engineering Committee's Substation Subcommittee who provided a great deal of
1 and effort to integrate the text and graphics into one whole document.

Finally our special thanks and appreciation to Allgeier Martin & Associate, Inc. who provided the
substation photo on the cover page.

BLAINE D. STOCKTON
Assistant Administrator
Electric Program

38. An example of an outage consideration for a
substation would include a transmission switching

Station that operates with a simple main bus. An
age ofthe bas results in a complet inten
tion of power through the substation, The

mgineer will need to consider other equipment in
the substation, such as a transfer bus or diferent
muli-bus arrangement, The engineer should also
evaluate the adjacent system to determine i x
Toad can be divened around the substation fo
outages to minimize the equipment hat is
installed in a substation

39. ample of confusion over the definition
‘of terms tha ean be experienced exist fr ih
term “outage.” An industrial firm with a
‘arible-speed drive (VSD) required a minimum
number of outages on the incoming feed since
‘ny otage resulted in the drive down,
Several hours” delay in the retar, and possible
environmental consequences during the outage
The utility reviewedits own outage criteria and
determine it met the customers requirement
Alter instalation, the customer complained
bout the large number outages forcing the VSD.
motor 0 de-nergize Further discussion

revealed the customers definition of outage was
ny voltage drop of 20 percent or more for more
than three cycles, The wily’ defini

Outage was any discontinuance of ser

ali o oeder filo

of common terms real

10 the instal

41. requirements when equipment À

Med. These requirements shoul
bbe considered with the utility
ability to serve the load during any

48. ‘Alaska Note: a
For coastal areas and islands,
‘use nearest contour

49. KI Special Wind Region
+ Population Center

Location V mph_(nvs)
705

Hawal (7)
Puerto Rico 125 (56)
[Guam 170 (76)
Virgin Islands 125 (56)
[American Samoa 125 _ (56)

1. Values are 3-second gust speeds In miles per hour (mis) at 33 ft
(10m) above ground for Exposure C category and are associated
with an annual probability of 0.02.

2. Linear interpolation between wind speed contours is permitted.

3. Islands and coastal areas shall.use wind speed contour of coastal
area

4. Mountainous terrain, gorges, ocean promontories, and special wind
regions shall be examined for unusual wind' conditions.

60. ons,
(Glow PHASING AND, TERMINAL
DESIGNATION ON VECTORS)

INFORMATION SAME AS
INCLUDE ALL IMPEDANCES
INCL "ON MVA Bast

61. ure = TPE
NO — FR = TPE

_ A
— KV BIL

KV BIL

62. 3 - MFR - TYPE

__ KV
{OR MFR CAT. NO.)

63. à CONN

Depicrs “INTERRUPTING MEDIUM

à ror arr
6 For ott
a“ VER vacuum
tine oo

— MFR = TYPE

66. DRAWOUT VACUUM NED. VOLTAGE

POWER CIRCUIT BREAKER

CIRCUIT BREAKER (LOW VOLTAGE)

RESISTANCE OR HEATING ELEMENT
ACTOR

DISCONNECT ON DRAWOUT CONNECTION

GROUND CONNECTION

STRESS RELIEF DEVICE

TEST SWITCH (POT. OR ISOLATION)

TEST SWITCH (CURRENT SHORTING)
INDICATING LIGHT
FIBER-OPTIC CIRCUIT

MICROWAVE PATH

67. ARROW INDICATES
DIRECTION OF TRIPPING

DO To OTHER RELAYS
X METE! REQUI
POTENTIAL CONNECTIONS, AS
REQUIRED, AT RIGHT ANGLES
TO CURRENT CONNECTIONS

To POTENTIAL
SOURCE

«A PARTIAL LISTING OF Di

A (FOR AMMETER)
V (FOR VOLTHETER)
W (FOR WATIMETER)
WH (FOR WATT-HOUR METER)
VOUT AMPERE REACTIVE METER)

WITH ANSI STO, €;

21 (DISTANCE RELAY)
7 (UNDERVOLTACE RELA
(DIRECTIONAL POWER RELAY)
(INSTANTANEOUS OVERCURRENT RELAY)
(AC TIME OVERCURRENT RELAY)
(AC DIRECTIONAL OVERCURRENT RELAY)
(ALARM RELAY)
(DIFFERENTIAL PROTECTIVE RELAY)

70. CRE

130. TYPICAL, ONE-LINE DIAGRAM

Gain

PLAN VIEW—TYPICAL BAY

Xx 4
TLEVATIN=TWICAL BY

134. Ea CE

PLAN VIEW-TYPICAL BAY
ELEVATION TYPICAL BAY

135. TYPICAL ONE-LINE DIAGRAM

PLAN VIEW—TYPICAL BAY

ELEVATON—TYPICAL BAY

137. ls
y
T

AP

TYPICAL ONE-LINE DIAGRAM

PLAN VIEW—TYPICAL BAY

‘weve he

ELEVATION —TYPICAL BAY

138. Lina Lech, cree

143. SUMED

WAST OR SHIELD WIRE

149. Table 4-4: Typical Characteristics of Cap and Pin-Type Insulators. Ref. Std. ANSI C29.8-1985, Table 1
Reproduced with permission of the National Electrical Manufacturers Association.

BIL(IMPULSE | TECHNICAL | UPRIGHT CANTILEVER] UNDERHUNG CANTILEVER! BOLT
WITHSTAND) | REFERENCE ‘STRENGTH ‘STRENGTH CIRCLE HEIGHT |LEAKAGE DISTANCE

Kv NUMBER | POUNDS | (NEWTONS) | POUNDS | (NEWTONS) | IN] CM] m. | CM | m Cm
5 T 2,000 6.896) 7,000 aaa | 3 [ren] 75 [as] 75 | om
95 si 4,000 (17,792) 3,000 asus | 3 |e} 8 || 8 (20.3)
110 4 2,000 (6.896) 1.000 gag | 3 [762] 10 | @54| 120 | (05)
110 44 4,000 (17,792) 3,000 aaa | 5 |a2n| 10 | @s4| 140 | (56)
150 7 2,000 (6.896) 1.000 aa) | 3 | 762)| 12 | @o5)| 200 | (508)
150 46 4,000 (17,792) 3.000 aaa | 5 [an] 12 | Gos| 180 | (457)
190 147 3,000 (13/344) 2.000 esos) | 3 |(762)| 145 | (668)| 260 | (660)
200 10 2.000 (6.896) 1,000 (ss | 3 |os)| 15 | Gen] 280 | (710
200 49 4,000 (17,792) 3.000 aaa | 5 can] 15 | Gan} 280 | win
210 140 7.000 (31,196) 4,000 (7792) | 5 can] 145 | G68| 330 | (638
210 141 10.000 | (44,480) 6.000 esse) | 5 |(127| 15 | Ges} 330 | (838
210 142 10.000 | (44,480) 6.000 (25.588) | 7 |(17e| 145 | Ges} 330 | (838)
210 191 20.000 | (88,960) 12,000 (3.376) | 7 |(78| 145 | Win] 330 | (838)
210 164 4,000 (17,792) 3,500 (15,568) | 3 [ee] 145 | (668)| 330 | (838)
250 13 2,000 (6.896) 1,000 (ses | 3 | 762)| 18 | 457] 360 | (014)
250 165 3.000 (13,344) 2.000 esse | 3 |7e2| 18 | (57| 360 | (0140
350 16 1.500 (6672) 1,000 was) | 3 | (762)| 2 | (737)| 50 | (1320)
350 56 3.000 (13,344) 2,350 (10,453) | 5 | 127] 280(1) | 73.7} 660 | (168.0)
350 166 2,000 (6896) 2,000 (ses) | 3 | (7.62)| 2801) | can | 680 | (168.0)
560 19 1,700 (7562) 1.470 (6539) | 5 | (127)| 43.5(1) |(111.0)] 990 | (2520
550 167 1,000 (4,448) 1.000 was | 3 | 762) | 43.5(1) [(1110)| 990 | (2520)
650 170 1.000 (4,448) 1:000 (4.448) | 3 |(762)| 540(1) | (1372)| 1080 | (2743)
750 168 1,000 (4,448) 1,000 was) | 3 | (7.62 | 58.0(1) | (1473) | 1320 | (9353)
750 25 1200 (6.338) 1.070 (4759) | 5 | (127 | 58.0(1) |(1470)| 1320 | (35.0)
750 123 2.000 (6.896) 1,750 are | 5 | (127)| 58.0(1) | (147.0)] 1320 | (350
900 126 910 (4.048) 840 (736) | 5 |(127)| 725(1) | (1840)| 1650 | (4190)
900 27 1450 (6.450) 1,350 (6005, | 5 |(127)| 725(1) | (1840)| 1650 | (419.0)
1050 128 750 (3.336) 700 rs | 5 | (12.7)| 87.0(1) [@210)| 1980 | 603.0)
1050 28 1,170 (5204) 1,100 ws) | 5 |(127)| 87.o(1) |(221.0)| 1980 | (6030
1050 196 2300 (10,230) 2.300 (10,230) | 7 |(178)| 871 |(210)| 198 | (503.0)
1300 133 1,000 (4,448) 950 (4.226) | 7 | (17.8)| 101.5(1) | (257.8) | 281 | (686.7
1300 197 2.000 (8.896) 2.000 ses) | 7 Jura | 101.511) | @57.8)| 231 | (6867
Notes:

(1) Does not include 3.5-inch (8.89 cm) high sub-base that is required for ful BIL.

(2) The insulators listed are representative of those currently available. Additional ratings are available for some voltages. Refer to
‘manufacturers’ data for information.

(3) The characteristics listed are typical. Refer to manufacturers’ data for actual ratings and additional characteristics.

150. Table 4-5: Typical Characteristics of Post-Type Insulators. Ref. ANSI Std. C29.9-1983, Tables 1 and 2.
Reproduced with permission of the National Electrical Manufacturers Association.

BIL (IMPULSE | TECHNICAL UPRIGHT UNDERHUNG BOLT CIRCLE
CANTILEVER CANTILEVER,
WITHSTAND) | REFERENCE ‘STRENGTH ‘STRENGTH TOP BOTTOM | HEIGHT TEAKAGE
DISTANCE
o_o m (CM)
7.62) | 75 |(1917| 105 | (287
(12.7) | 75 | (19:1) | 105 | (267)
(7.62) | 10 | (254) | 155 | (39.4)
(12.7) | 12 | (05) | 155 | (294)
(7.62) | 14 | (356) | 24 | (510)
(27) | 15 | @8n)| 24 | (610)
(7.62) | 18 | (45.7) | 37 (94)
(12.7) | 20 | (50.8) | 37 (94)
(7.62) | 22 | (55) | 43 | (109)
(127) | 24 | (610) | 43 | (109)
(7.62) | 30 | (762) | 72 | (183)
(127) | 30 | (762) | 72 | (183)
(127) | 45 | (114) | 99 | (251
(127) | 45 | (114) | 99 | (251
(12:7) | ss | (137) | 116 | ss)
(127) | 54 | (137) | 116 | (295
(127) | 62 | (157) | 132 | (335)
(12.7) | 62 | (157) | 132 | (335)
(127) | 80 | (203) | 165 | (419)
(12:7) | 80 | (208) | 165 | (419)
(12.7) | 92 | (234) | 198 | (503)
(127) | 92 | (234) | 198 | (503)
(173) | 92 | (234) | 198 | (503)
(12.7) | 106 | (269) | 231 | (587)
(178) | 106 | (269) | 231 | (687)
(178) | 106 | (260) | 231 | (587)
(178) | 106 | (269) | 231 | (687)

kv NUMBER _ [POUNDS | (NEWTONS) | POUNDS | (NEWTONS)
95 202 2000 (8896) 2000 (8896)
95 202 4000 | (17782) 4000 (17792)
110 205 2000 (8896) 2000 (8896)
110 225 4000 | (17792) 4000 (17792)
150 208 2000 (6896) 2000 (8896)
150 227 4000 | (17792) 4000 (17792)
200 210 2000 (8896) 2000 (8896)
200 231 4000 | (17792) 4000 (17792)
250 214 2000 (8896) 2000 (8896)
250 267 4000 | (17792) 4000 (17782)
350 216 1500 (6872) 1500 (6672)
350 278 3000 | (13344) 3000 (13344)
550 286 1700 (7562) 1700 (7562)
550 287 2600 | (11564) 2600 (11564)
650 288 1400 (6227) 1400 (6227)
650 289 2200 (9786) 2200 (9786)
750 291 1200 (5338) 1200 (5338)
750 295 1850 (8229) 1850 (8229)
900 304 950 (4226) 950 (4226)
900 308 1450 (6450) 1450 (6450)
1050 312 800 (3558) 800 (3558)
1050 316 1250 (5560) 1250 (5560)
1050 362 2300 | (10230) 2300 (10230)
1300 324 1000 (4448) 1000 (4448)
1300 367 1450 (6450) 1450 (6450)
1300 368 2000 (8896) 2000 (8896)
1300 369 2050 (9118) 2050 (9118)
Notes:
(1) The insulators listed are representative of those currently available. Additional ratings are available for some voltages. Refer to manufacturers’ data for
information,
(2) The characteristics listed are typical. Refer to manufacturers’ data for actual ratings and additional characteristics.

E

Cm

7.82)
(12.7)
(7.52)
(12.7)
(7.52)
(12.7)
(7.52)
(12.7)
(7.52)
(127)
(7-62)
(12.7)
(127)
(127)
(127)
(127)
(127)
(127)
(127)
(12.7)
(12.7)
(127)
(178)
(127)
(127)
(178)
(12.7)

2

152. Pt
¡aaa

= SÍ
> VA VA

Sy

|
À
|

166. PROFILE AND WIND DIRECTION

Z
©

4% = RATIO OF SPAN LENGTH TO VERTICAL DIMENSION OF BUS CONDUCTOR

175. UREMENT DIRECT