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DESIGNANDCONSTRUCTIONSTANDARDS

ELECTRICAL SERVICE LINE

2015

714 FOURTH AVENUE, SUITE 100 FAIRBANKS, ALASKA

PO BOX 74040 FAIRBANKS, AK 99707

(907) 455‐1500

WWW.DOYONUTILITIES.COM

ii

Distribution And Construction Standards Electrical Service Line

Revisions between 2014 Standard and 2015 Standard

Item or Location Description of Revision

SPECIFICATIONS

Cover Sheet Date “2014” changed to “2015”

All pages after Cover Sheet

Date in footer: “2014” changed to “2015”

TABLE OF CONTENTS

First Line Removed “2013”

Page 1 ‐ INTRODUCTION

Last paragraph added “To ensure equipment quality and to decrease the likelihood that the facility contractor will be required to replace newly installed equipment (at contractor expense) prior to electric hookup, all service equipment must be approved by DU via the submittal review process before installation. When service equipment is provided by DU,”

DESIGNANDCONSTRUCTIONSTANDARDSELECTRICALSERVICELINE

TABLEOFCONTENTS

2015 iii Doyon, Utilities, LLC

LIST OF REVISIONS……………………………………………………………………………………………………………………………….….ii

TABLE OF CONTENTS……………….………………………………………………………………………………………………………….….iii

INTRODUCTION ............................................................................................................................................. 1

SECTION 1 ‐ ELECTRICAL SERVICE STANDARDS ............................................................................................. 3

1.1 SERVICENAMINGCONVENTION ............................................................................................... 3

1.2 TYPICALPERMANENTOVERHEADSERVICE,TYPEA(NOTTOEXCEED200AMPS) .......... 5

1.3 TYPICALPERMANENTOVERHEADSERVICE,TYPEB(NOTTOEXCEED200AMPS) ......... 9

1.4 TYPICALPERMANENTUNDERGROUNDSERVICE(NOTTOEXCEED200AMPS) ............. 16

1.5 TYPICALMULTIPLEMETERSERVICEENTRANCE(SIXUNITSORLESS) ............................ 19

1.6 TYPICALMULTIPLEMETERSERVICEENTRANCE(MORETHANSIXUNITS) ................ 24

1.7 TYPICALCTMETEREDSERVICE(1000AMPSORBELOW) .................................................. 28

1.8 TYPICALCTMETEREDSERVICE(GREATERTHAN1000A) .................................................. 35

1.8.1 NEWCONSTRUCTION: ...................................................................................................... 35

1.8.2 RENOVATION/UPGRADES: .............................................................................................. 36

1.9 SHUNTTRIPREQUIREMENTS ................................................................................................. 36

1.10 PRIMARYMETERING ................................................................................................................ 36

SECTION 2 ‐ METERING AND SERVICE RELATED STANDARDS AND DETAILS .............................................. 39

2.1 SELF‐CONTAINEDMETERSOCKETS(100AND200AMPS) ................................................. 39

2.2. CURRENTTRANSFORMERMETERSOCKET ........................................................................... 39

2.3 GROUNDING ............................................................................................................................... 43

2.4 METERING/SERVICEEQUIPMENTLOCATIONREQUIREMENTS ......................................... 46

2.5 GUYINGDETAILS ....................................................................................................................... 46

2.5 ALUMINUMCONDUCTORSUBSTITUTIONTABLE ................................................................. 48

2.6 TRANSFORMERIMPEDANCEVALUES .................................................................................... 49

SECTION 3 – SERVICE APPLICATION CHECKLIST AND FORMS ..................................................................... 51

3.1 LOADANDPRINTINFORMATIONREQUIREDBYDU ............................................................ 53


2015 1 Doyon Utilities, LCC

INTRODUCTION Doyon Utilities (DU) standards of construction shall be utilized for all facilities to be owned, operated and maintained by the utility, to include hookups from the utility facility to the demarcation point. Generally, utility mains/distribution lines will be constructed by DU or by DU's contractor at DU expense. Thus, these standards will be followed by DU contractors. DU will be responsible for planning, designing and constructing utility water, wastewater, gas, heat mains and electrical distribution system improvements for new government facilities. This will require close cooperation and utility involvement in the government facility planning process. Without this coordination, facilities constructed will have no utility service. The government, Army, or Corps of Engineers will not be responsible for design, construction, or oversight of any utility owned facilities, whether main/distribution, lines, or hookups. Doyon Utilities will be responsible for construction of the hookup for the utility from the building to the utility main/electrical distribution system facility as described below:

Electric: The electric hookup will be from the transformer to the load side of the disconnect. The utility will provide and install the meter. At a minimum for overhead services, Doyon Utilities will install the overhead service drop from the transformer to the service entrance mast. At a minimum for underground services, Doyon Utilities will install the service lateral from the transformer to the service side of the first (main) disconnect.

In most installations, Doyon will provide and install the service equipment up to and including the first (main) disconnect. However, in rare circumstances (with prior written approval of the utility), the facility contractor may be tasked with installation of the service entrance equipment at DU expense, including but not limited to meter base, CT enclosure, main disconnect, service entrance grounding, shunt trip devices, and mast/service entrance conduits. Regardless of installation, Doyon Utilities will own, operate and maintain the service hook‐up from the service transformer up to and including the first disconnect downstream of the transformer, which is the service point of demarcation. Regardless of the installer, the service entrance equipment shall be installed in accordance with these Electrical Service Line Standards as well as applicable local, military, and national codes. To ensure equipment quality and to decrease the likelihood that the facility contractor will be required to replace newly installed equipment (at contractor expense) prior to electric hookup, all service equipment must be approved by DU via the submittal review process before installation. When service equipment is provided by DU, coordination will be necessary so that the appropriate meters and equipment are on hand for the facilities to be constructed.



For new services or service upgrades, a completed Service Application including a request for service coversheet, all DU required load and print information and the appropriate Electric Service Checklist is required before work will begin by DU to provide service. See Pages 51‐58 of these Standards for samples of these forms. The conductor size and material that the customer intends to land on the Doyon’s disconnect is imperative to include on the Coversheet, this allows DU to provide the appropriate provisions for the customer to terminate their conductors. Without this information, the customer may be responsible to pay for the additional costs incurred to change out the loadside lugs. After receipt of paperwork and a site inspection has been completed, if DU determines that any of the customer’s electrical installation doesn’t meet all pertinent current electrical codes, they have the option to refuse service until such time code violations are rectified. Although Doyon will be responsible for installation of service equipment up to and including the main disconnect, Doyon Utilities is not responsible for correctly sizing the service entrance equipment and conductors in accordance with the NEC, including the grounding electrode conductor. The facility designer will be responsible for correctly designing those items and submitting the required sizes to Doyon with the Service Application. Doyon will size the service equipment, conductors and main breakers in accordance with the information provided on the Service Application. Doyon can supply customers with the following secondary voltages for both overhead and underground:

1. Single Phase, 120/240V, 3 wire 2. Single Phase, 240/480V, 3 wire 3. Three Phase, 120/208V, 4 wire* 4. Three Phase, 277/480V, 4 wire*

If a secondary voltage other than the above is required, contact DU. Three Phase service may not be available to all locations, DU will advise of the additional costs associated with providing three phase service where there is currently only single phase available.



SECTION1‐ELECTRICALSERVICESTANDARDS 1.1 SERVICENAMINGCONVENTION

In general, the service designation and detail will adhere to the following naming convention, SS‐AA‐B‐C D, explained as follows:

SS refers to Service Standard and is the first two letters of all service types.

AA refers to the service amperage rating and indicates hundreds of amperes of the

service rating, i.e SS‐01 would be for a 100 Amp Service, and SS‐12 would indicate a

1200 Amp Service.

B refers to the voltage of the service based on a numbering code, where 1=240/120V,

2=208/120V, 3=480/240V, and 4=480/277V

C refers to type of service entrance feed type, T=Top Feed (Overhead) and B=Bottom

Feed (Underground)

D is only applicable for Top Feed Services and refers to the style of deadending the

overhead service drop, where H=House Knob and M=Mast type deadending.

So, for example, a 200 Amp, overhead, 1‐phase 240/120V service on the gable end of building where the mast does not penetrate the roof would be indicated by SS‐02‐1‐T‐H. A 600 Amp, underground, 3‐phase 480/277V service would be indicated by SS‐06‐4‐B Additional suffixes may be added to the service name to indicate additional features, like –G indicates group metering service entrance and ‐GM indicates a group metering installation with an overall main disconnect.



1.2 TYPICALPERMANENTOVERHEADSERVICE,TYPEA(NOTTOEXCEED200AMPS)1. Refer to detail SS‐AA‐B‐T‐M schematic and material lists (pages 5‐9)

2. Service Entrance Conductor shall extend out of the weather head a minimum of 18”.

3. Conductors shall be phased taped using the following convention: 120/240:Black/Red,

240/480:Brown/Orange, 120/208:Black/Red/Blue, and 277/480: Brown/Orange/Yellow

4. All service entrance masts that extend above the roof line shall be a minimum 2" rigid

metal conduit (RMC) or intermediate metal conduit (IMC) and shall be guyed using

minimum 1/8" aircraft cable and approved clamp. See Roof Guy Detail on page 47.

5. If roof overhang is less than 2 feet, provide suitable protection for meter from ice and

snow. Protection by overhanging roof is preferred. An acceptable alternative is a protective

hood made of 18 gauge (minimum) galvanized steel, fastened at the roof edge or wall, and

extending out a minimum of 6" beyond face of meter and 6" on each side of the service

equipment.

6. The use of split‐bolts is not allowed.

7. Couplings in the conduit shall be below roof line.

8. Telephone drop may not be attached to mast. See NEC 230.28.

9. Meter base shall be able to handle a ring‐type meter, with test bypass. Ringless are not

acceptable.

10. Meter base shall be per the material call out or approved equal.

11. Locking provisions shall be factory installed, no field installed or modified locking provisions

are acceptable.

12. Contractors shall provide and maintain a minimum 4 ft. wide clearing between service

entrance and the Doyon Utilities pole.

13. Utility service drop is limited to a maximum 150' span.

14. See NEC 230.24 for required clearances over roof. If Army requirements call for vertical

clearance of service drop conductors to be greater than 3 ft. or a flat roof is classified as

accessible, then the mast assembly and guying will be designed by a qualified engineer.

Mast designs shall be submitted to the Doyon Utilities Engineering Services Department for

review prior to installation.

15. Conductor insulation shall be type XHHW‐2.

16. Maintain all NEC required clearance at all times. See NEC 230.9 and 230.24.

17. lf the grounding electrode conductor is exposed to physical damage it shall be run in

conduit securely fastened to the structure. See NEC 250.64(B).

18. Install sealing lock nuts or hubs on all conduit penetrations of outdoor enclosures.

19. Install intersystem bonding termination per NEC 250.94. Doyon doesn’t allow the use of

the NEC exceptions under this rule in any circumstance.

20. AIC Ratings of Specified Equipment are 10K AIC, except for 200 Amp, 480V Service, which

are 22K AIC. If Engineer determines higher ratings are required, adjust equipment callouts

accordingly.



1.3 TYPICALPERMANENTOVERHEADSERVICE,TYPEB(NOTTOEXCEED 200AMPS)

1. Refer to detail SS‐AA‐B‐T‐H schematic and material lists (pages 11‐15)

2. Service drop conductors shall be above or at least 36" from any door, opening window,

building vent, or other building opening.

3. Service Entrance Conductor shall extend out of the weather head a minimum of 18”.

4. Conductors shall be phased taped using the following convention: 120/240:Black/Red,

240/480: Brown/Orange, 120/208: Black/Red/Blue, and 277/480: Brown/Orange/Yellow

5. The use of split‐bolts is not allowed.

6. Telephone drop shall be more than 12" (vertical clearance) below power cable at all points.

See NESC 235C1, Exception 3.

7. Conductor insulation shall be type XHHW‐2.

8. If the grounding electrode conductor is exposed to physical damage it shall be run in conduit

securely fastened to the structure. See NEC 250.64(B).


10. Meter base shall be able to handle a ring‐type meter, with test bypass. Ring less aren’t

acceptable.

11. Meter base shall be per the material call out or approved equal.

12. Locking provisions shall be factory installed, no field installed or modified locking provisions

are acceptable.

13. Contractors shall provide and maintain a minimum 4 ft. wide clearing between Service

entrance and the Doyon Utilities pole.

14. Utility service drop is limited to a maximum 150' span.

15. Maintain all NEC required clearance at all times. See NEC 230.9 and 230.24.

16. Install intersystem bonding termination per NEC 250.94. Doyon doesn’t allow the use of the

NEC exceptions under this rule in any circumstance.



accordingly.



1.4 TYPICAL PERMANENT UNDERGROUND SERVICE (NOT TO EXCEED

200AMPS)

1. Refer to detail SS‐AA‐B‐B schematic and material lists (pages 17‐19)

2. Service entrance location shall be approved by DU and shall be located as close as possible

to existing DU facilities.

3. Conduit for service cable shall be sized per NEC but shall not be less than 2 inches.

4. The Army Facilities' service equipment shall conform to the NEC and State of Alaska Codes

and shall be inspected and approved prior to connection of service by DU.

5. Any deviation from this standard shall be approved in writing by DU's Engineers.

6. If grounding electrode conductor is exposed to physical damage it shall be run in conduit


7. Equipment shall be mounted so that center of meter is located at height of 5’‐0” minimum

and 6’‐0” maximum above grade.


9. Service Lateral Conductors shall be phased taped using the following convention:

120/240:Black/Red, 240/480:Brown/Orange, 120/208: Black/Red/Blue, and 277/480:

Brown/Orange/Yellow





accordingly.



1.5 TYPICALMULTIPLEMETERSERVICEENTRANCE(SIXUNITSORLESS)

1. Refer to detail SS‐04‐B‐B‐G schematic and material lists (pages 21‐23)









7. The bottom of the service entrance equipment shall not be less than 36" above finished

grade or finished floor. Choose equipment size to maintain this minimum distance and

maximum height of 6'‐7" to the horizontal centerline of the highest breaker or handle of the

disconnecting means.




Brown/Orange/Yellow



11. Coordinate additional requirements with DU if overhead service is desired for this type of

installation.

12. AIC Ratings of Specified Equipment are 10K AIC. If Engineer determines higher ratings are

required, adjust equipment circuit breaker callouts accordingly.

22

23



1.6 TYPICALMULTIPLEMETERSERVICEENTRANCE(MORETHANSIXUNITS)

1. Refer to detail SS‐AA‐B‐B‐GM schematic and material lists (pages 25‐27)




4. The Army facilities' equipment shall conform to the NEC and State of Alaska Codes and shall

be inspected and approved prior to connection of service by DU.


6. The bottom of the service entrance equipment shall not be less than 36" above finished

grad or finished floor. Choose equipment size to maintain this minimum distance and

maximum height of 6'‐7' to the horizontal centerline of the highest breaker or handle of the

disconnecting means.




Brown/Orange/Yellow.



10. AIC Ratings of Specified Equipment are 10K AIC. If Engineer determines higher ratings are

required, adjust equipment circuit breaker callouts accordingly.



1.7 TYPICALCTMETEREDSERVICE(1000AMPSORBELOW)

1. Refer to detail SS‐AA‐B‐B schematic and material lists (pages 29‐34)

2. The maximum ampacity of a new overhead service shall be limited to 200 Amps without

special permission from Doyon Utilities. If a service greater than 200 Amps is required than

it will be served by an underground connection.






6. CT cabinet, meter enclosure, and main disconnect(s) shall be grouped together on the

outside of building. All enclosures shall be raintight (NEMA 3R). Inside locations are not

permitted without written Doyon approval prior to installation.

7. Conduit for conductors between CT’s and Meter shall be at least 1 inch diameter and no

longer than 30 feet. Conduit shall be GRS. Conduit used for CT circuits shall be of the

threaded type.

8. CT's shall be mounted at right angles to enclosure panels with polarity marks facing source

side.

9. DU shall install CT secondary wiring and test switch.




12. Conductor insulation shall be type XHHW‐2 for conduit installations.



Brown/Orange/Yellow



15. AIC Ratings of Specified Equipment are 65K AIC for 120/208V services, 35K AIC for 400

Ampere and 600 Ampere 277/480V services, and 50K AIC for 800 Ampere and 1200 Ampere

277/480V services. If Engineer determines higher ratings are required, adjust equipment

callouts accordingly.



1.8 TYPICALCTMETEREDSERVICE(GREATERTHAN1000A)

1.8.1 NEWCONSTRUCTION:

Ft. Wainwright and Ft. Greely: At the time of design of a new service greater than 1000A, Doyon shall be notified. It is the intent of Doyon to append a metering and main breaker section or sections to the Building MDP and have it integrated into the MDP from the MDP manufacturer. Doyon will provide the contractor procuring the MDP with their requirements and reimburse the facility contractor for the cost adder of the additional Doyon sections. Coordination with Doyon Utilities during the facility design process will be required. The following minimum requirements shall be met for these installations:

1. Adequate interior working space shall be provided for the interior installation.

Refer to the interior Doyon service equipment working space detail (page 37)

for minimum requirements.

2. The metering and CT section of the MDP shall be built to EUSERC standards for

the ampacity and voltage of the service size. The CT section shall include

removable bus sections to accommodate window type CT’s appropriate for the

ampacity of the switchgear.

3. The main breaker shall include a shunt trip module for connection to exterior

located shunt trip knife switch. The MDP shall also include a 15A, 1 pole breaker

to power the shunt trip circuit. At Doyon’s discretion and expense, they may

request the facility electrical contractor install the shunt trip circuit and shunt

trip disconnect on the exterior of the building. See pages 36, 38 and 39 for

shunt trip requirements and details.

4. CT meterbases for these installations shall be installed on exterior of building

and accessible to DU employees. The conduit for conductors between CT’s and

Meter shall be installed by the facility electrical contractor, and shall be at least

1 inch diameter and no longer than 30 feet. Conduit shall be RMC.

5. In locations where an exterior CT meterbase is not feasible or cannot meet the

requirements of item 4, written acceptance of an interior meter location from

DU is required. In such instances, the installation shall include installation of a

1” RMC from the meter location to a DU accepted location on exterior of the

building to accommodate installation of a remote meter reading antenna on the

exterior of the building.

6. The service equipment shall conform to the NEC and State of Alaska Codes and

shall be inspected and approved prior to connection of service by DU.

7. DU employees shall have access to service equipment installed indoors in

facilities at all times.



JBER Richardson: At the time of design of a new service greater than 1000A, Doyon shall be notified. It is the intent of Doyon to supply a metering and main breaker/disconnect section on the exterior of the building. Only with Doyon’s written approval shall any of their equipment be located inside. Such interior installations shall meet the requirements noted above.

1.8.2 RENOVATION/UPGRADES:

Ft. Wainwright and Ft. Greely: At these above posts, the first choice is to modify existing installation to add a metering and main breaker section. It is imperative to contact Doyon Utilities at the time of planning to determine the feasibility of this retrofit. If an interior retrofit isn’t possible, DU will install their equipment on the exterior. In the case where exterior mounting is chosen, DU will reimburse the Army for the work required to reconnect the new service equipment to the existing equipment within the building. JBER Richardson: At Richardson any electrical service renovation work will include relocating the service equipment outside if applicable. DU will reimburse the Army for the work required to reconnect the new service equipment to the existing equipment within the building.

1.9 SHUNTTRIPREQUIREMENTSA minimum 8” x 8” Red Placard with White Letters shall be installed at each Shunt Trip location. The Placard shall read “Service Shunt Trip Utility”. In the case of multiple shunt trips for the same building, the placard shall also indicate specifically which room the main breaker is located in and the panel voltage it controls. The shunt trip switch shall be of the safety switch style and disconnect the main breaker in the off position. Handle shall be lockable in the ON and OFF position. See Shunt Trip details on page 38.

1.10 PRIMARYMETERINGWhere primary voltage metering is desired, coordinate with Doyon Utilities for primary metering availability and requirements.

37

38

39



SECTION2‐METERINGANDSERVICERELATEDSTANDARDSANDDETAILS

2.1 SELF‐CONTAINEDMETERSOCKETS(100AND200AMPS)

1. Manual bypass sockets are not allowed unless specifically approved by DU prior to

installation; all meter bases shall be of the Test Block Bypass style.

2. As required by NEC 110.15 the phase conductor in the service entrance having the higher

voltage to ground shall be identified by the color ORANGE, and be located on the right hand

lug of the meter base (4‐wire delta only).

2.2. CURRENTTRANSFORMERMETERSOCKET

1. Meter base enclosure for any of the above metering configurations shall include provisions

for a DU provided test switch. The maximum distance between the meterbase and CT’s

shall be 30’ assuming the use of #10 CU XHHW‐2. In applications where this distance will be

exceeded, contact DU to determine if the actual distance is acceptable, given the exact CT’s

and conductor that will be used on the project.

2. Unless specific variance is granted by DU, DU shall provide and install the meterbase, CTs

and test switch, including wiring.

3. As required by NEC 110.15, the phase conductor in the service entrance having the higher

voltage to ground shall be identified by the color ORANGE, and be located on the right hand

lug of the meter base. (4‐wire delta only).

4. If the test switch doesn’t have built in capabilities of shunting the neutral wires together,

this shall be done.

5. Individual wires between the X2 on each CT and each test switch phase neutral is required.

One wire between the test switch and CT cabinet isn’t allowed.

6. Depending on the manufacture of the test switch, the X1 and X2 locations may be swapped

from detail. The X1 position(hot) identified by determining which switch has the shorting

fingers. At the time of this writing, the wiring diagram shows a Millbank style test switch

with X1 on the left. Cooper B‐Line’s normal standard is the exact opposite; however, they

are intending to provide Doyon with test switches that conform to the same standard as

Milibank (X1 on the left). Contact Doyon if there is a question on the identification of X1.

7. For single phase CT services, see Meter Connection Diagram 4S on page 41.

8. For three phase CT services, see Meter Connection Diagram 9S on page 42.

41

42



2.3 GROUNDING

1. Bond grounding electrode conductor to metal water pipe and other available grounding

electrodes as required by NEC 250.50 “Grounding Electrode System”.

2. If grounding requirements of NEC 250.50 cannot be met, and made electrodes are utilized

as the sole type of grounding electrodes, then the resistance requirements of NEC 250.56

shall be met. Electrodes may be directly bonded together with grounding electrode

conductor, individually routed to the neutral bus, or connected to an optional terminal bus

as stated in item 12. A ground rod is required by DU even if a metal water pipe or other

electrodes listed in NEC 250.50 are used.

3. For new construction, it is the responsibility of the facility electrical contractor to provide

and install the grounding electrode conductors and bonding, sized and installed in

accordance with the requirements of NEC article 250, for each of the available electrodes of

the building listed in NEC 250.52. Sufficient additional conductor shall be left coiled at the

service entrance to allow connection to the service entrance ground bus without splicing the

conductor. Auxiliary grounding electrodes (ground rods) at the service entrance shall be

installed by DU or DU’s contractor.

4. Supply side equipment bonding jumper shall be sized in accordance to NEC 250.102(C) with

minimum size to be #4 CU as required by DU. Equipment bonding jumper shall be

continuous throughout service equipment.

5. Grounding electrode conductors sized in accordance to NEC 250.66 with minimum size to be

#4 CU in accordance with DU requirements. For specific service entrance, see approved DU

load data for minimum permissible grounding electrode conductor size. See item 12 for

another grounding electrode bonding jumper connection option. Grounding conductors

shall be continuous as per NEC 250.64(C) and protection from physical damage as per NEC

250.64(B).

6. Use #4 CU conductors to bond CT meter enclosure. CT meter bonding conductor shall be

continuous between bonding points.

7. All neutral buses shall be either directly or indirectly effectively bonded to enclosures in

accordance with NEC 250.92. Install separate grounding lug in enclosure if neutral bus is not

directly bonded to enclosure. Factory supplied neutral bus bonding means are subject to

approval.

8. Per NEC 250.12 and 250.96, paint shall be removed from surfaces in contact with grounding

fittings. Exposed metal at ground points shall be protected with conductive corrosion

inhibitor.

9. Equipment bonding jumpers and CT meter bonding conductor shall be routed through the

conduit. Each end of the conduit shall be bonded as required by DU.

10. Threadless couplings and connectors are not allowed for bonding service equipment. OZ

Gedney Type CHM‐T or similar UL listed with piercing screw approved for bonding are



acceptable for bonding bushings. Standard locknuts or sealing locknuts are not acceptable

for bonding at service equipment.

11. Compression or screw‐type connectors are acceptable means of splicing conductors. Split

bolt type are not allowed.

12. Optional terminal bus can be added to connect bonding jumpers form multiple grounding

electrodes. Optional terminal bus shall be effectively bonded to enclosure. A grounding

electrode conductor shall connect the optional bus with the neutral bus and it shall be sized

as per NEC 250.66.



14. At all newly constructed facilities with concrete foundations, it is the facility contractor’s

responsibility to install an appropriate concrete encased grounding electrode per NEC

250.52‐A(3). The facility contractor shall also install a copper grounding electrode conductor

from the concrete encased electrode to the service entrance equipment location for

connection to the service grounding electrode system. That grounding electrode conductor

shall be sized in accordance with NEC 250.66.

15. See Grounding Detail on page 45 for typical service entrance grounding detail.

45



2.4 METERING/SERVICEEQUIPMENTLOCATIONREQUIREMENTS

1. Whenever possible, metering and service equipment shall be installed nearest Doyon’s

primary facilities to minimize the extension of the required primary system. Coordinate

with Doyon Utilities during facility design to determine optimal location for metering and

service equipment.

2. For services less than 1200A at Ft. Wainwright and Ft. Greely, metering and service

equipment shall be located on the exterior of the building unless Doyon provides written

consent that the location may be on the interior. At JBER Richardson, any variance from

locating the metering and service equipment on the exterior requires written consent.

3. At locations that require multiple metered services, all equipment shall be grouped

together.

4. Metering and service equipment shall be readily accessible to Doyon at all times and not in a

locked location, unless Doyon has granted permission to the contrary.

5. Metering and service equipment shall be located in a safe, non hazardous, above ground

location that is free from mechanical damage including falling snow and ice.

6. Metering and service equipment shall be mounted on a rigid surface, with an attachment

system capable of securing the full weight of the equipment in accordance with applicable

codes and standards.

7. Metering and service equipment shall be located so to allow a minimum of 5’ working space

around the equipment without any obstacles.

8. Metering equipment shall be mounted such that the meter is at a height between 60” and

72” above final grade, with a desired height of 66”. In the case of multiple meters, the

equipment shall be centered at 66” whenever possible, while still maintaining a maximum

height of 72”. The preferred location of the center of the disconnect(s) is 66”, where there

are multiple disconnects, the middle of the uppermost disconnect(s) handle shall not be

greater than 79”.

9. Meter base shall maintain a minimum of 3’ away from gas facilities.

10. Doyon shall have access to the meter at all times without prior notification.

2.5 GUYINGDETAILS

1. See page 47 for service mast guying details.

2. No other attachments are permitted on the mast.

3. For mast heights greater than 60” contact DU. Mast designs shall be submitted to DU’s

Engineers for review and approval prior to installation.

47



2.5 ALUMINUMCONDUCTORSUBSTITUTIONTABLE1. See page 49.

49



2.6 TRANSFORMERIMPEDANCEVALUES The table below shows the assumed % impedance and phase angle for distribution transformers on the transformer base. Where fault current involves on one‐half of the low voltage winding, the % impedance values, based on full rated kVA, are 1.5 and 1.2 times the full winding %R and %X respectively. An infinite bus is assumed on high side of the transformer. If a overhead transformer bank is feeding the service, the %Z that shall be used in fault calculations is the %Z for one of the OH transformers. EX: 112.5kVA(3‐37.5kVA) bank is feeding service, use %Z of 1.6.

Distribution Transformer Size [kVA/Phase]

% Impedance [% Z]

Phase Angle [degrees]

% R +jX [% Z]

5 2.1 30 1.819 + j1.050

10 1.6 30 1.386 + j0.800

15 1.6 40 1.226 + j1.028

25 1.6 45 1.131 + j1.131

37.5 1.6 45 1.131 + j1.131

50 1.6 52.5 0.974 + j1.269

75 1.6 52.5 0.974 + j1.269

100 1.6 60 0.800+ j1.386

150 1.7 60 0.850 + j1.472

167 1.7 60 0.850 + j1.472

225 1.7 60 0.850 + j1.472

300 1.7 60 0.850 + j1.472

500 1.7 60 0.850 + j1.472

750‐2000 5.75 60 2.875 + j4.980



SECTION3–SERVICEAPPLICATIONCHECKLISTANDFORMS

Doyon Utilities, LLCWO# (for Doyon’s Use)

COVER SHEETELECTRICAL LOAD DATA AND ELECTRICAL PRINT

Application Name Telephone

Business Name Telephone

Mailing Address

New Service Location

Architect/Engineer Telephone

Electrical Contractor Telephone

Mailing Address

AK Specialty Contractor License#

Service Requested Amps Configuration: Volts

DU has adopted the National Electrical Code (NEC) as the minimum standard acceptable for electrical installations it serves. The Contractor should be aware that in addition to NEC requirements there may be more stringent requirements imposed by the Utility.

DU requires a detailed electrical print and detailed listing of the electrical load by a registered electrical engineer or licensed electrical contractor on all multi-residential, commercial and industrial services. Please ensure all applicable information required on the list below is attached to this cover sheet.

Checklist of Required Information

Site PlanConnected Load

Motors and StartersDiversified DemandElectrical Print

Typical Electrical Service ChecklistConductors and ConduitsOver-current Device(s)Meter(s) Equipment Bonding and GroundingSealing ProvisionsReduced Neutral Calculations

When you have submitted the required information, DU will prepare a “ Service Entrance Equipment Requirement” sheet. A copy of this sheet will be sent to the applicant. DO NOT ORDER equipment prior to receiving this “Service Entrance Equipment Requirement” sheet.

Load and Print Data Submitted by Date

Load and Print Data Received by Date

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3.1 LOADANDPRINTINFORMATIONREQUIREDBYDU Site Plan Site plan shall include property lines or adjacent roadways; location of structure to be served by utility with respect to the property lines or roadways; location of service entrance equipment; location of DU transformer pole that is to serve your structure; distance between DU transformer pole and your service entrance equipment. Site plan shall be provided in AutoCAD format. Connected Load and NEC Load Calculation Provide the total connected load in kilovolt‐amps (kVA) as well as the NEC service load in kVA, computed in accordance with the current edition of the National Electric Code. This calculation shall be performed by or under the supervision of a registered professional electrical engineer. Motors and Starters: DU conducts a motor starting study for motors 10 horsepower and larger. If the load contains motor(s) rated 10 horsepower or larger, then the following data is required for each motor:

o Rated horsepower

o NEC locked‐rotor indicating code letter

o Voltage

o Indicate whether single phase or three phase

o Indicate motor starting method (full voltage, reduced voltage [auto

transformer], or drive)

o Indicate motor starting and running sequence for multiple motors

Diversified Demand: If the load is a dwelling type load, then the demand (in kilowatts) shall be the load computed per the current edition of the National Electric Code. It shall include a calculation for the individual dwelling units as well as the total load on the service equipment. Electrical Print Include a one‐line diagram AND riser diagram of service equipment from service entrance conductors through the main disconnect and describing all physical details of installation. Although not required at initial application, these prints should be stamped by a professional electrical engineer registered in the State of Alaska, and Doyon Utilities may request a set of stamped drawings prior to service hook‐up. Refer to the typical electric service checklists on pages 55 and 56.

o Conductors and conduits ‐ type, insulation, size, and number

o Over‐current Device(s) and Equipment AIC rating



o Meter(s) ‐ including numbering system

o Equipment Bonding and Grounding ‐ per NEC and DU Electrical Service Entrance

Requirements

o Sealing Provisions ‐ All access to unmetered conductors or bussing shall have

provisions for installing split/lock seals in accordance with DU Service Security

Equipment Sealing program. All meter retaining rings shall be the screw type.

More detailed information is available on request.

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