Front Accessible Power-Zone 4 Switchgear

Flexibility

• 42” depth allows Power-Zone 4 switchgear to be used in more applications

• Suitable to mount against a wall or back to back

• Excellent for e-house applications as it removes the need for outer doors/work platforms resulting in cost savings for the building

• Expand into areas where switchgear previously would not fit

• Wide range of drawout circuit breaker arrangements to optimize footprint

Quality and Reliable Construction

• High short circuit/withstand ratings to support critical facilities

• Compartmentalized, maintenance-friendly switchgear with options for arc flash mitigation

• Captive splice and front accessibility speed installation and maintenance

• Industry leading MasterPacT drawout, stored-energy circuit breaker

• Standard, repeatable designs are factory wired, programmed, and tested in an ISO9001 facility

Advanced Technology

• Direct Ethernet circuit breaker connectivity for growing data communication needs

• EcoStruxure Power solutions from Schneider Electric to meet energy control and monitoring needs at every level

• Ability to retrofit aging infrastructure with latest smart technology

Technical Features

• ANSI C37.20.1 Rated. Listed to UL1558 & CSA C22.2, No. 31

• MasterPacT stored energy, drawout circuit breaker rated per ANSI C37 and Listed to UL1066

• Sections rated to 3200 A horizontal bus, 3200 A vertical bus

• Incoming mains or tie breakers up to 3200 A

• Feeder circuit breakers to 2000 A

• Bus short circuit ratings up to 100 kA, 635 Vac

• Bus short time withstand rating (60 cycle) up to 100 kA, 635 Vac

• Circuit breaker short circuit ratings up to 100 kA @ 508 Vac and 85 kA @ 635 Vac.

• Breaker short time ratings up to 85 kA, 635 Vac

• NEMA Type 1 enclosures

• Single or multiple main options

• 42-inch deep footprint

• Main sections with incoming cable provisions are 26 inches wide

• Main/Tie sections combined with feeders begin at 44 inches wide

• Feeder sections begin at 44 inches wide

• Silver plated bus (tin plated or insulated bus is optional)

• SPDs, high resistance grounding resistor/controls, communication networking and PowerLogic power meters/monitors are available

• A circuit breaker floor crane is available.

• NEMA Type 1 and Drip/Sprinkler Resistant Enclosures available

Floor space can be a premium in a number of ways:

• Additional construction cost of electrical room square footage

• Loss of building space for production (i.e. hospital beds, process lines, storage, etc.)

• Additional conditioned space costs

An example of Space savings is shown below. Front accessible lineups are wider than rear accessible lineups but have the advantage of eliminating the need for rear/side aisleways. The aisleway depth (front or rear) is mandated by NEC/CEC and is typically from 36-42 in. deep. Front Accessible switchgear shown requires only front aisleway as all breakers and cable access is in front.

The results on this typical example saved 37% of the original rear accessible footprint when considering the rear aisleway. This can present significant savings considering construction costs per square foot.

Significant savings in outdoor Electrical Houses (E-house) construction can be achieved when using Power-Zone 4 Front Accessible Switchgear. Traditional rear accessible switchgear requires a large interior footprint as shown above; or if the lineup is placed against one of the building’s walls, an additional working platform and access doors are needed on the outside of the building to gain access to the switchgear rear compartments. Front accessible switchgear only requires access from the front, eliminating the cost and need for these outside provisions as shown in eHouse.

The ability to reshape the switchgear lineup and eliminating the need for rear access can make front accessible switchgear the only choice for some room layouts. The ability to place Power-Zone 4 drawout switchgear against a wall or back to back with other equipment is possible as shown below. This allows switchgear to still be a viable solution in more places.

Power-Zone 4 Front Accessible Switchgear is based on the same rugged ANSI structure design as rear accessible Power-Zone 4 for critical applications. Each section has steel barriers separating the breaker from bus/cable compartments. Main sections can be offered in 2 types: Main Only or Main with Feeders. On the left end of the lineup shown in Front Accessible Single Main, Top Incoming Cable 70 in. W X 42 in. D total is a Mains Only section. These must always be shipped with a corresponding Feeder section in a shipping split. Main Circuit breakers can also be provided in the same section as a Feeder section as shown in Front Accessible Bottom Incoming Main with Feeders
58in. W X 42 in. D. These 2 main designs allow optimization of footprint based on feeder count. For more layout details, see Layout Arrangements and Section Widths section of this catalog.

Sections can be provided with optional barriers between them and between the cable and bus compartments to provide a fully compartmentalized lineup.

Horizontal wireway, top and bottom allow for control cabling requiring only front accessibility as shown in Front Accessible Single Main Section + Feeders Section, Doors Open. Shipping spit terminal blocks and pluggable communication cables are provided for reconnection of shipping split wiring at site. When running wires vertically down the section, ample room to the right of each breaker compartment is provided. Thanks to front-facing cable compartments wiring is not needed to the rear and virtually all control wiring can be accessed from the front.

Front Accessible Power-Zone 4 Switchgear is available in NEMA Type 1 enclosures only. Ventilation of the enclosure is necessary to cool bus, breaker and cable compartments to meet stringent ANSI C37.20.1 UL temperature rise tests. Vents are included on rear of enclosure and on top and front of cable compartments as shown in Rear View of Front Accessible PZ-4 showing vents:

The overhead lifter is not available on Front Accessible PZ-4 due to top conduit areas overlapping the lifter rail. A floor crane is available in 2 styles for lifting the breaker out of the section and transporting away from the gear for maintenance. See Breaker Racking, Moving and Handling Options section for further information

Other enclosure options for front accessible include Drip Hoods and Sprinkler Resistant design which includes drip hoods, transparent breaker covers, ventilation louvers, and cover/door gasketing (See Sprinkler Resistant Enclosures section for more details)

Each feeder section is divided into 4 cells containing MasterPacT MTZ2 or NW standard width breakers. The breaker compartment for the feeder section is always on the left with its corresponding cable compartment always on the right. Auxiliary and Instrumentation Compartments are also available in place of breaker compartments. Breaker cells are contained in steel compartments to barrier them from bus or cable areas. Other features of rear accessible Power-Zone 4 switchgear are featured on front access construction.

Circuit Breaker Types:

Mains/Ties are available from 1600 – 3200 A. Feeder are available from 800 – 2000 A. MicroLogic X (MTZ) and MicroLogic S, A, P, H (NW) are available.

Breaker features, accessories, and performance in the front accessible offering are the same as featured in the rear accessible offering. See Circuit Breakers section for details on breakers.

The front facing cable compartment in front accessible Power-Zone 4 provides the same function for cables entering the lineup as rear accessible. However, the accessibility from the front can provide an easier maintenance process. Covers are standard on the cable compartment with optional padlockable doors available. Cables can be routed for top or bottom entry. In the case of a main in the same section as feeders the feeders must exit the opposite direction of the main. Conduit entry areas are similar to rear accessible and are shown in Front Facing Conduit Entry Area.

One key feature provided by the cable compartment in front accessible Power-Zone 4 is the ability to access splice connections from the front via the cable compartment. This allows for completion of the horizontal cross bus installation from the front of the gear. A unique rotating splice design is used to provide a captive splice bar which rotates counterclockwise to create the splice between sections (see Rotating Splice Bus).

In front accessible PZ-4, the vertical bus and horizontal bus are contained in the rear compartment separated from the breakers by steel barriers. As shown in Bus Compartment at Rear the rear is not accessible as all splicing and maintenance can occur from the front. As in rear accessible all bus joints consist of SAE Grade 5 hardware and conical spring (e.g. Belleville ) washers to withstand mechanical forces exerted during short circuits. These are considered maintenance free joints. Horizontal cross bus is mounted at the bottom or top depending on incoming main power direction.

Sectional Side barriers between bus and cable compartments can be added optionally for further isolation. A neutral bus can be added up to 150% capacity of the main phase bus. In addition, a full-length ground bus is provided with front splicing capability. Optional bus mounted CT’s can be mounted in the compartment and wired to front accessible shorting terminal blocks.