Equipment Advisory

Adv. No. 2015-006 R0 Supersedes: N/A

Issue Date: January 30, 2015 File: 1649.10

Information Bulletin: Equipment and Connection Changes for Secondary Underground Customer Services, 120/240 V up to 600A, Single Phase

1.0 Items Covered Customer owned secondary service equipment. ES53 S1-01.01 SECONDARY CUSTOMER SERVICES SINGLE PHASE UP TO TO 600 A 120/240 V REVENUE METER SOCKET CONNECTIONS S1-01.09

2.0 Overview This bulletin contains major improvements to the secondary services developed over the past few years by BC Hydro and various equipment manufacturers.

CEC Part I 2012 Rule 6-206(3) permitted installation of the customer service main outside of the building, which facilitated development and approval of an integrated assembly comprising service main and revenue meter socket. In July 2014, Hydel Enterprises introduced CSA approved 400 A 120/240 V wall mounted, integrated assembly for improved service connection and safety access to the integral 400 A CT block. In addition to the wall mounted integrated assembly, other manufacturers offer free-standing pad-mounted kiosk type 400 A and 600 A service assemblies. BC Hydro did not have applicable distribution standards for such service connections.

The majority of 120/240 V services for single family dwellings, rated for 200 A or less, have a relatively low fault withstand and interrupting rating of 10 kA or less, including the corresponding BC Hydro self-contained revenue meters. Current development trend for high density subdivisions necessitate the use of larger pad-mounted transformers, such as 100 kVA or 167 kVA, having high available fault currents, which could be located at short distance away from the customer services. New distribution standards have been developed to provide a method of limiting the high available fault currents to below 10 kA using current limiting fuses.

Occasionally, 400 A 120/240 V customer services are located within the 3 m critical touch potential zone of BC Hydro LPT, i.e. 167 kVA supplying two adjacent fourplex buildings. For these installations, customer must install a gradient ground control

This Advisory is for the information of personnel working on BC Hydro’s distribution equipment, and is not for public distribution. Page 1 of 3

Adv. No. 2015-006 R0 conductor, as necessary around the service enclosure - below ground, to mitigate elevated touch potentials.

3.0 Action All customer underground secondary single phase services up to 600 A 120/240 V supply shall be installed in compliance with the applicable rules of CEC Part I 2012 and amendments by BCSA. In addition, all services shall comply with BC Hydro Requirements for Secondary Revenue Metering Installations (750 Volts or Less).

https://www.bchydro.com/content/dam/BCHydro/customer-portal/documents/accounts-billing/forms-guides/requirements-secondary-72.pdf

Prior to any installation, the customer shall submit proposed service equipment drawings to BC Hydro designer, clearly showing the sealing and locking provisions, the size of utility cable compartment, size and type of conductor termination lugs and access for BC Hydro personnel. Furthermore, the following requirements shall be met:

a. All customer service equipment shall have adequate bus extensions and cable lugs inside utility compartment for cable terminations. Termination of service conductors into the lugs of the customer service main will no longer be acceptable.

b. All unmetered conductors and bus work shall be assembled inside sealed cable ducts or metal enclosures having BC Hydro seal for restricted access by BC Hydro personnel only.

c. External hinged cover doors on outdoor type customer service equipment, shall be equipped with a double hasp for the installation of customer as well as BC Hydro padlocks.

d. BC Hydro designer or a consultant shall calculate the available fault current for 120/240 V services and specify current limiting fuses – if necessary.

e. Customer service main for 400 A or 600 A services shall be rated for 22 kA minimum fault withstand and interrupting.

f. Large 400 A and 600 A service equipment must not be installed inside the building - regardless of the unrestricted access to BC Hydro personnel. An electrical closet on the side of a building, a free-standing outdoor type kiosk, detached building or a power shed located on customer’s property - having unrestricted access for BC Hydro personnel – are acceptable to BC Hydro.

g. Customer service equipment or a revenue meter socket, located less than 3 m away from BC Hydro LPT shall have adequate gradient control conductors connected to the customer service building ground.

This Advisory is for the information of personnel working on BC Hydro’s distribution equipment, and is not for public distribution Page 2 of 3