Low Voltage Switchgear
Magnum DS Switchgear
Eaton's line of Cutler-Hammer Magnum DS Switchgear is backed by 50 years of power circuit breaker and switchgear development that have set industry standards for quality, reliability, maintainability and extended operating life. Magnum DS Switchgear is an assembly of metal enclosures housing power circuit breakers, and normally include control and measuring devices such as relays, instruments, meters and the necessary power bus work and control wiring for AC systems applications up to 600 volts.

Application Description
Switchgear is utilized in the protection, controlling, and monitoring of low voltage distribution systems. Although used as "stand-alone" distribution assemblies, they are quite often incorporated into secondary unit substations so that the equipment can be located more closely to the point of power utilization. Magnum DS Switchgear is ideally suited for all types of industrial, commercial and utility applications with distribution systems rated 600 volts or below.

Features, Benefits and Functions
Standard Finish - Light gray paint finish (ANSI 61) using a modern completely automated and continuously monitored electrostatic powder coating. This continually monitored system includes spray degrease and clean, spray rinse, iron phosphate spray coating spray rinse, non-chemical seal, oven drying, electrostatic powder spray paint coating and oven curing.

Integral Base - The rugged formed base greatly increases the rigidity of the structure and reduces the possibility of damage during the installation of the equipment and is suitable for rolling, jacking and handling. A lifting angle is permanently welded into the bus compartment structure for increased strength.

Heavy Duty Door Hinges - Each breaker door is mounted with hinge pins. Removal of the door is easily accomplished by just lifting the hinge pin. This allows easy access to the breaker internal compartment for inspection and maintenance.

Rear Cover/Doors - In Magnum DS Switchgear standard rear covers with captive hardware are the bolt-on type. They are split into two sections to facilitate handling during removal and installation. Optional rear doors are also available.

Through the Door Design - The following functions may be performed without the need to open the circuit breaker door: levering the breaker between positions, operate manual charging system and view the spring charge status flag, close and open breaker, view and adjust trip unit and read the breaker rating nameplate.

Front Accessible - When the door is open or removed each breaker compartment provides front access to isolated, vertical wireways, primary disconnects, cell current transformers and other breaker compartment accessories for ease of field wiring and troubleshooting field connections.

Four Position Drawout - Breakers can be in connected, test, disconnected or removed position. The breaker compartment door can be closed in the connected, test and disconnected positions.

Closing Spring Automatic Discharge - Mechanical interlocking automatically discharges the closing springs when the breaker is removed from its compartment.

Breaker Inspection - When withdrawn on the rails, breaker is completely accessible for visual inspection; tilting is not necessary. The rails are permanent parts of every breaker compartment. Interference interlocks are supplied on breakers and in compartments where the compartments are of the same physical size to assure an incorrect breaker cannot be inserted.
Standards and Certifications
Magnum DS Switchgear assemblies have undergone an extensive seismic qualification program. The test program utilized ANSI standard C37.81, the Uniform Building Code (UBC) and the California Building Code (CBC) as a basis for the test program. The assemblies have been tested and qualified to exceed these requirements. Magnum DS Switchgear conforms to the following standards: NEMA SG3 and SG5, CSA, ANSI C37.20.1, C37.51, and UL Standard 1558 and is built in an ISO certified facility.

Primary and Secondary Unit Substations
Often Switchgear Assemblies are configured as unit substations. A Unit Substation, as referred to in this publication, is defined as a coordinated assembly consisting of 3-phase transformers with high-voltage incoming line sections and an assembly of low-voltage distribution sections, with the following parameters:
Transformer kVA - 112.5 through 3750
Low-Voltage - 208, 240, 480 or 600V
Unit Substations may be indoor or outdoor, with a selection of high-voltage incoming sections, a choice of transformer types and an arrangement of Switchgear to suit the application. Unit substations follow the system concept of locating transformers as close as practicable to areas of load concentration at utilization voltages, thus minimizing the lengths of secondary distribution cables and buses. This concept provides several basic advantages, such as:

. Reduced power losses
. Improved voltage regulation
. Improved service continuity
. Reduced likelihood of faults
. Increased flexibility
. Minimized installation expense
. Efficient space utilization
. Complete coordination, both mechanical and electrical
. Flexibility with wide choice of components and ratings to meet exact application requirements
. Meets all applicable ANSI, IEEE, NEMA and UL Standards