Siemens 480V manual Construction Details, General, Finish, Assembly Construction

480V Metal-Enclosed Switchgear

Construction Details

General

General

The Siemens 480 volt switchgear assem- bly consists of one or more metal- enclosed, vertical sections. Normally the end sections are designed to allow for installation of future sections.

Each vertical section consists of up to four individually enclosed breaker or auxil- iary compartments which are sized to provide uniform height.

Included in each assembly are various components such as circuit breakers, instrumentation and control equipment, transformers, relays, three-phase bus work, and all internal wiring, connectors, and other supporting equipment.

In accordance with ANSI C37.20.1, the maximum temperature for parts that are handled is 50°C. The main bus maximum temperature rise is 65°C above 40°C ambient. The temperature rise of the air surrounding the cable connection points is limited to 45°C above 40°C ambient.

Finish

During construction, the structural steel parts, panels, and compartments are all prepared for painting by a five-stage wash system. Standard finish color is light gray ANSI 61. If a different finish color is required, it is applied over the standard finish with conventional spray equipment and is allowed to air cure. The completed finish has a nominal 2 mils dry film thickness.

Assembly Construction

Siemens metal-enclosed power switchgear is constructed of preformed, full-depth, 14-gauge steel sheets bolted together and reinforced with cross-mem- ber braces to form a rigid, self-supporting compact assembly. The top and rear plates, and side sheets are all 14-gauge steel. When two vertical sections are mounted together, two sheets of 14- gauge steel separate adjacent circuit breaker compartments.

Bolted steel / glass polyester compart- ments housing each power circuit break- er are mounted in the vertical section to form the switchgear assembly. This iso- lates the circuit breakers from the bus / cable section and from adjacent circuit breaker compartments.

The bus / cable section includes main horizontal bus, riser bus, connections from the main bus to each set of primary disconnects, and load side copper run- back bus.

Grounded metal barriers can be provided to isolate the main bus from cable con- nections. Barriers are also available to isolate the incoming line to the main cir- cuit breakers from the main load bus of the switchgear.

c

b

a

e

d

aInter-Unit Wiring Trough

bMeter and Auxiliary Compartment c Ventilation and Lifting Structure d Telescoping Breaker Drawout Rails

e Ventilation Openings (RL-2000, RL-3200, RL-4000 and RL-5000)

4

480V Metal Switchgear- Enclosed

CSI Section 16470	Siemens Electrical Products and Systems	51
	Specification Guide