Section Cover Page
Section 260924
2010-11-01 Low Voltage Switching

This Master Specification Section contains:

.1 This Cover Sheet

.2 Specification Section Text:

1. General

1.1 Related Requirements

2. Products

2.1 Components

3. Execution

3.1 Installation of Switches

3.2 Relay Cabinets

3.3 Wiring

3.4 Low Voltage Switch Wiring

BMS Basic Master Specification
Alberta Infrastructure
Master Specification System / Page 0
Section 260924
Plan No: Low Voltage Switching
Project ID: Page 2

1. General

1.1 RELATED REQUIREMENTS

.1 Electrical General Requirements: Section260010.

.2 Identification: Section260553.

2. Products

2.1 COMPONENTS

.1 Power supply transformers:[347/24V] [120/24V] as required, rated at 35VA current limiting type, complete with selenium rectifier on the 24V side.

.2 Low voltage relays:electrically operated, mechanically held, rated at 20A, mounted in rubber grommets.

.3 Low voltage switches:momentary contact, rocker action type, [] bakelite with clearly identified "On" and "Off" positions. Key operated switches of matching type. Pilot light type switches of matching type with red integral pilot light.

.4 Cabinets:Code gauge metal, prime coated, locking door, flush hinge, lock and latch assembly.

.5 Barrier cabinet into two compartments, one for line voltage wiring and one for 24 V wiring.

.6 Barriers to be full height, full depth and containing 20mm knockouts.

.7 In each cabinet, provide space for relays and spacers indicated and a minimum of two transformers.

.8 Provide terminal strips in both compartments for termination and connection of line and low voltage wiring. Line voltage terminal strips to be rated at 600V.

.9 Backboard:17mm G.I.S. fir plywood, one piece per installation.

3. Execution

3.1 INSTALLATION OF SWITCHES

.1 Install low voltage relay switches complete with mounting brackets and plates.

.2 Mount 1, 2 or 3 switches in single gang box, with box mounted horizontally and four switches in a 2 gang box.

.3 Provide special back box with one piece stainless steel faceplate when housing more than four switches.

3.2 RELAY CABINETS

.1 Mount metal cabinet on backing board to [] height.

3.3 WIRING

.1 Leads for line and low voltage connections to be 250mm length minimum.

.2 Strap or clip wiring into position.

3.4 LOW VOLTAGE SWITCH WIRING

.1 [No.18AWG] [] [colourcoded], installed [in conduit] [in conduit within walls or above nonremovable ceilings and exposed in other areas. Band multiple groups of wiring together.]

END OF SECTION

2010-11-01 BMS Version