Liebert® EXM™ Distribution Cabinet

2.1.1 Unpacking and Preliminary Inspection

A quality installation begins on the receiving dock.

1. Inspect the shipment for damage or signs of mishandling before unpacking the unit(s).
2. If the Liebert EXM Distribution Cabinet was shipped in an export crate, open the shipping crate carefully. Use care to avoid puncturing the container with sharp objects that would damage the contents.
3. Remove the packing and vapor barriers and inspect the equipment for any obvious shipping damages.

4. If any damage is observed, immediately file a damage claim with the shipping agency and forward a copy to:

Vertiv Corporation
1050 Dearborn Drive
P.O. Box 29186
Columbus, Ohio 43229 USA

2.1.2 Handling Considerations

The Liebert EXM Distribution Cabinet is bolted to a wooden pallet to allow handling by forklift equipment.

The Liebert EXM Distribution Cabinet is furnished with casters to allow the unit to be rolled into place after it has been unbolted from the pallet. The unit should be kept on the shipping pallet until it has been moved by forklift as close as practical to its installation location.

Refer to the cabinet drawings furnished with the Liebert EXM Distribution Cabinet for the unit's size and weight. Typical cabinet dimensions and weights are shown in Figures 1 and 2.

The route to the Liebert EXM Distribution Cabinet's installation area should be planned to ensure that all passages, including doorways, elevators, ramps and hallways, are large enough to accommodate the unit and that the floors are strong enough to support the weight. Determine whether any corners or offsets would cause problems in maneuvering the unit.

Vertiv recommends removing the exterior side panels, if supplied, before the unit is moved. This will prevent scratches, dents and other damage to the panels.

Figure 1: Typical cabinet and floor planning dimension data, 23.6" (600mm) cabinet

This figure shows the dimensions and layout of the 23.6-inch (600mm) Liebert EXM Distribution Cabinet. It includes front, side, and top views with measurements for width, depth, and height. Key areas indicated are the Base Pan, Ventilation Area, E-Box Cover, Customer Input Conduit Plate, Panelboard Output, and Ventilation Cover Plate. Detail views A, B, and C provide closer looks at specific connection points and dimensions. The text notes that input and output conduit plates can be exchanged for top or bottom cabling.

Table 1: 23.6-inch (600mm) cabinet weight

Figure 2: Typical cabinet and floor planning dimension data, 34.6" (880mm) cabinet

This figure illustrates the dimensions and layout of the 34.6-inch (880mm) Liebert EXM Distribution Cabinet. It presents front, side, and top views with detailed measurements. Indicated components include Ventilation Area, Input Conduit Plate, Subfeed Output Conduit Plate, and E-Box Cover. Detail views A and B highlight specific connection points and dimensions. The accompanying text states that input and subfeed conduit plates can be exchanged for top or bottom cable entry.

Table 2: 34.6-inch (880mm) cabinet weight

2.1.3 Unit Preparation

The Liebert EXM Distribution Cabinet may be easily removed from the shipping pallet and installed by customer personnel. A typical procedure is:

1. Set the pallet assembly in a level area where there is enough room to move the Liebert EXM Distribution Cabinet off the pallet onto the floor.
2. Remove side panels from the Liebert EXM Distribution Cabinet, if supplied. An Allen wrench for the side panels is furnished in the installation packet.
3. Remove the bolts and two mounting brackets holding the unit to the shipping pallet. Mounting brackets are located on either side of the unit.
4. Use a forklift to move the unit off the pallet. If a ramp is available from the pallet, it can be used to roll the distribution cabinet off the pallet onto the floor.
5. Roll the Liebert EXM Distribution Cabinet to the installation area. For units to be placed on a raised floor, use care when positioning unit over the floor cutout to prevent the casters from falling through the cutout.

2.1.4 Location Considerations

The Liebert EXM Distribution Cabinet should be placed near the load(s) it will supply, preferably within the data center.

Equipment location should employ the shortest output distribution cable runs consistent with logical equipment arrangement and allowance for expansion.

The Liebert EXM Distribution Cabinet is intended for indoor installation in an area with ambient temperatures of 32°F to 104°F (0°C to 40°C) with a relative humidity of 0% to 95% (non-condensing).

Bottom clearance is required for units with bottom entry/exit of cables. This clearance may be provided by a raised floor at least 6" (150mm) high. Figures 1 and 2 show the typical raised-floor cutout dimensions for cables and cooling airflow.

Recommended minimum service clearances are shown in Figure 3. The National Electrical Code (NEC) requires the indicated front and rear clearances for service access. Clearance above the unit is required for cooling airflow (exhaust).

As do all electrical devices, the Liebert EXM Distribution Cabinet produces heat under normal operation (see Table 3). This heat must be accounted for when calculating the environmental conditions of the room.

Figure 3: Recommended minimum front and top clearances

This diagram shows the recommended minimum clearances around the Liebert EXM Distribution Cabinet for ventilation and service access. It indicates an 18-inch (457mm) minimum clearance above the unit and a 36-inch (914mm) clearance at the front. The diagram also shows a front view of the cabinet.

Table 3: Liebert EXM Distribution Cabinet heat output

Figure 4: Wiring diagram, 480V Liebert EXM 600mm Distribution Cabinet with transformer for panelboard

This is a wiring diagram for a 480V Liebert EXM 600mm Distribution Cabinet with a transformer for a panelboard. It illustrates the connections for utility input with and without a breaker, the panelboard with main breaker and sub-breakers, and the transformer. It includes a legend for factory-supplied and field-supplied wiring, and notes regarding grounding electrode conductor installation.

Figure 5: Wiring Diagram, 480V Liebert EXM 600mm Distribution Cabinet with subfeed breakers

This diagram shows the wiring for a 480V Liebert EXM 600mm Distribution Cabinet configured with subfeed breakers. It details the input breaker, input without breaker, subfeed breakers, distribution busbar, and power block connections. A legend identifies factory-supplied and field-supplied wiring, and notes on grounding are provided.

Figure 6: Wiring Diagram, 480V Liebert EXM 880mm Distribution Cabinet with subfeed breakers

This wiring diagram illustrates the connections for a 480V Liebert EXM 880mm Distribution Cabinet equipped with subfeed breakers. It covers input breaker configurations, subfeed breakers, distribution busbar, and power block connections. The diagram includes a legend for wiring types and notes on grounding electrode conductor installation.

Figure 7: Wiring diagram, 480V Liebert EXM 880mm Distribution Cabinet with transformer for subfeed

This diagram details the wiring for a 480V Liebert EXM 880mm Distribution Cabinet that includes a transformer for subfeed applications. It shows input connections (with and without breaker), subfeed breakers, transformer connections, and distribution busbar. A legend and notes on grounding are included.

Figure 8: Electrical connection locations for 23.6" (600mm) cabinet

This figure displays the electrical connection points within the 23.6-inch (600mm) Liebert EXM Distribution Cabinet. It shows front and side views indicating the locations of the Panelboard Output, Input Breaker, Lug Set Mech for Input Breaker, and Ground Connection. It also indicates the Top Input Cable connection for stand-alone configurations.

Figure 9: Subfeed SF2 electrical connection location for 23.6" (600mm) cabinet

This diagram illustrates the electrical connection locations for subfeed SF2 in the 23.6-inch (600mm) Liebert EXM Distribution Cabinet. It shows the positions of the Subfeed Breaker, Ground Busbar, Input Breaker, and Lug Set Mech for Input Breaker, as well as the Subfeed Breaker Output and Neutral Bar.

Figure 10: Ground lug detail for 23.6" (600mm) cabinet

This figure provides detailed dimensions and specifications for the ground lug used in the 23.6-inch (600mm) Liebert EXM Distribution Cabinet. It shows the lug's dimensions, notes its marking requirements (UL, CSA), and specifies the wire range (14 AWG to 2/0 STR copper or aluminum).

Figure 11: Electrical connection location for 34.6" (880mm) cabinet

This figure shows the electrical connection locations within the 34.6-inch (880mm) Liebert EXM Distribution Cabinet. It displays the positions of the Subfeed Breaker, Input Breaker, and associated Lug Set Mech components for input breaker, subfeed breaker, subfeed neutral, and input/subfeed ground.

Figure 12: Subfeed SF6 electrical connection location for 34.6" (880mm) cabinet

This diagram illustrates the electrical connection locations for subfeed SF6 in the 34.6-inch (880mm) Liebert EXM Distribution Cabinet. It indicates the positions of the Subfeed Breaker, Input Breaker, and the Lug Set Mech components for input breaker, subfeed breaker, subfeed neutral, and subfeed ground. It also shows the Subfeed Breaker Output.

Figure 13: Lug details for 34.6" (880mm) cabinet

This figure provides details for various lugs used in the 34.6-inch (880mm) Liebert EXM Distribution Cabinet. It includes specifications for the Ground Lug Detail (Item No. 14014), Neutral Lug Detail (Item No. 421-337), and Input and Subfeed Breaker Lug (Item No. 552950P1), including port count, conductor range, and torque specifications.

2.2.1 Input Power Connections

The 3-phase power input to the Liebert EXM Distribution Cabinet is supplied directly from the Liebert EXM UPS.

The input feeder circuit should be sized in accordance with the NEC and any local building codes to ensure the feeder's ability to safely carry the system's full load current, including losses.

Typical conductor size data is shown in Table 5. All connections must comply with the NEC and all other applicable codes.

The main input feeder should consist of 3-phase conductors and one (safety) ground conductor (3W + G).

Stand-alone distribution cabinets have an input circuit breaker; attached distribution cabinets do not have an input circuit breaker.

Figure 14: Typical Liebert EXM 600mm Distribution Cabinet equipment arrangement

This diagram shows a typical equipment arrangement for the Liebert EXM 600mm Distribution Cabinet system. It illustrates the layout of a Battery Cabinet #1, UPS, MBC, and Distribution Cabinet, with overall dimensions and notes on clearances, cable entry, and positioning.

Figure 15: Typical Liebert EXM 880mm Distribution Cabinet equipment arrangement

This figure depicts a typical equipment arrangement for the Liebert EXM 880mm Distribution Cabinet system. It shows the configuration of Battery Cabinet #1, UPS, MBC, and Distribution Cabinet, including overall dimensions and important notes regarding clearances, cable entry, and component placement.

2.2.2 Equipment Grounding

Equipment grounding is primarily for safety. Correct implementation of grounding also enhances equipment performance. All power feeders must include equipment grounding means as required by the NEC and local codes.

An insulated ground conductor is recommended to be run in each feeder conduit. Ground conductors must be at least the minimum size per NEC Table 250-66. Larger wire sizes may be used for increased system performance.

If the input power feeder conduit is used as a grounding conductor, adequate electrical continuity must be maintained at all conduit connections.

2.2.3 Grounding Electrode Conductor for Liebert EXM Distribution Cabinets with Transformer

Required by code - The Liebert EXM Distribution Cabinet with transformer must be grounded according to the safety practices of NEC 250-26. A local grounding electrode conductor is recommended in addition to the equipment safety ground which is normally run with the input power conductors. (See Figures 8 through 13.)

2.2.4 Output Power Connections

Output circuit breaker(s) and/or panelboards with ground and neutral provisions are provided inside the unit for connecting load(s) as required. (See Figures 8 through 13.)

Code Compliance—All output cables and connections must comply with the NEC and all other applicable codes.

3.1 Internal Inspection

A detailed internal inspection should be performed after the unit is in place and before it is energized, to ensure trouble-free startup. The same internal inspection should be carried out when performing preventive maintenance.

Open the unit - Gain access to the internal components of the Liebert EXM Distribution Cabinet unit by removing the exterior panels and internal accent panels.

Visually inspect - Be sure wiring and components are not damaged.

Check power connections - Check all power connections for tightness. Refer to Tables 8 through 11 for torque requirements of all electrical connections.

Perform formal detailed inspection - Follow the procedures described in 5.0 - Inspection and Startup Checklist when performing detailed inspection.

3.2 Startup

Checklists

Follow the detailed step-by-step checklist (5.0 - Inspection and Startup Checklist) when installing and starting up the Liebert EXM Distribution Cabinet.

Initial System Startup

A qualified electrician must be employed to perform the equipment inspection and startup. Liebert system startup may be arranged by calling your local Vertiv sales representative or Vertiv. In the United States, call 1-800-543-2378.

Warranty

A copy of the appropriate checklist (furnished with the equipment) must be completed, signed, dated and returned to Vertiv. Warranty coverage of the equipment is not effective unless the checklist has been received by the factory.

4.1 Startup Procedures

Before the unit is placed into service after initial installation, after equipment relocation, or after equipment has been de-energized for an extended period of time, perform equipment inspection and startup procedures as detailed in 3.0 - Equipment Inspection and Startup and 5.0 - Inspection and Startup Checklist.

After initial system startup, the following guidelines can be used for standard equipment operation. These guidelines should be reviewed for any special equipment modifications, special site considerations or company policies that may require changes to the standard equipment operation.

5.1 Exterior Inspection

Exterior Inspection Checklist

• Confirm that the exterior of the unit is undamaged.
• Confirm that service and ventilation clearances are adequate. (See Figure 3).

5.2 Internal Inspection

A detailed internal inspection should be performed after the unit is in place and before it is energized to insure trouble-free startup. The same internal inspection should be carried out when performing preventive maintenance.

Gain access to the internal components of the Liebert EXM Distribution Cabinet™ unit by removing the external and interior side panels.

5.2.1 Interior Inspection Checklist

• Inspect all wire and conductor insulation for damage.
• Check all breaker connections for tightness. Retorque if necessary. Unless otherwise labeled, use the recommended tightening torque as shown in Table 10.
• Check all terminal block connections for tightness. Retorque if necessary. Unless otherwise labeled, use the recommended tightening torque as shown in Table 11.
• Verify that input phase cables A, B and C are properly connected to the input breaker (standalone units) with the correct phase rotation. Refer to Figures 4 and 7 for additional details. When the Liebert EXM Distribution Cabinets are attached, the input power connects to a busbar or transformer.
• Verify that the input ground cable connects to the internal customer ground busbar.
• Verify that the internal customer ground busbar is connected to the Liebert EXM Distribution Cabinet frame.
• Verify that the output neutral cable is connected to the internal customer ground busbar.
• Verify that the output ground cable is connected to the internal customer ground busbar.
• Remove any foreign objects from the components or the interior area of the unit.

5.3 Startup

A qualified electrician should be employed to perform the equipment inspection and startup. Liebert system startup may be arranged by calling your local Vertiv sales representative or Vertiv. In the United States, call 1-800-543-2378.

A copy of the appropriate checklist (furnished with the equipment) must be completed, signed, dated and returned to Vertiv. Warranty coverage of the equipment is not effective unless the checklist is received by the factory.

5.3.1 Startup Checklist

• Make certain that all circuit breakers are in the Off position and that power to the unit is locked out.
• Verify proper input power connections to unit, including the equipment grounding conductor.
• Turn On the building power to the unit.
• Check the phase rotation at the input busbars. Phase rotation should be A, B, C, left-to-right.
• Check and record the input voltage. Measured voltages should correspond to the unit's nameplate input voltage.

Input Voltage Measurements:

Volts, Phase A to Phase B = ______

Volts, Phase B to Phase C = ______

Volts, Phase C to Phase A = ______

• Check the phase rotation at the panelboard main breakers. Phase rotation should be A, B, C, left-to-right.
• Check the phase rotation at the transformer output. Phase rotation should be A, B, C, left-to-right.
• Check and record the input voltage at each of the panelboard main breakers. Measured voltages should correspond to the unit's nameplate input voltage.

If output voltage or phase rotation is incorrect, check for wiring errors or incorrect input voltage, Contact Vertiv at 1-800-543-2378) in the USA or the local factory representative for assistance.

• Turn On the panelboard main breakers.
• Replace internal and external panels, if supplied.

6.1 Repair

Even the most reliable equipment may fail. Vertiv is at your service to ensure fast repair of your unit and minimum downtime of your installation.

Standard electrical troubleshooting procedures should be used to isolate problems in the unit. If there are questions, don't hesitate to contact Vertiv.

Repair or replacement of standard items, such as circuit breakers, fuses, transformers, capacitors and indicator lights can either be handled by qualified electricians or referred to Vertiv.

Repairs related to the monitoring system should be referred to Vertiv. To contact Vertiv for information or repair service in the United States, call 1-800-543-2378.

6.2 Inspection and Cleaning

Air circulation through the cabinet may cause dust to accumulate on internal components. Cleaning should be done as necessary during electrical inspections.

Annual general system inspections, cleaning, and operation checks are recommended to ensure system performance and long service life.

6.2.1 Inspection Schedule

• It is difficult to establish a schedule for periodic cleanings because conditions vary from site to site. Inspections after the first 24 hours, 30 days and 6 months of operation should help determine a pattern for the inspection schedule.
• Electrical connections and component mountings should be inspected after the first 24 hours, 30 days, and 6 months of operation. Inspections should be conducted annually thereafter.
• Ventilation openings and grilles should be inspected and cleaned every 6 months to one year.
• A complete inspection and operational checkout should be performed annually. This is best done by performing the inspection and startup procedure as detailed in 5.0 - Inspection and Startup Checklist.
• Vertiv offers a complete range of preventive maintenance services. These include thorough equipment performance checks and calibration of electronics. Contact Vertiv in the United States by calling 1-800-543-2378 for details.

Table 4: Physical standards and parameters

Table 5: Suggested minimum input wire size data--208V Units

Input data with Transformer (3-Phase + Ground)

Subfeed (3-Phase + 2 Neutral + Ground)

Table 6: Suggested minimum input wire size data--480V Units, No Transformer

Input data without Transformer (3-Phase + Ground)

Subfeed (3-Phase + Ground)

Table 7: Main input circuit breaker interrupt rating

* Refer to unit specification sheet for units equipped with non-standard main input breakers.

Table 8: Torque specifications, general

Table 9: Panelboard main circuit breaker torque specifications

Table 10: Branch circuit breaker torque specifications

Table 11: Terminal block compression lug torque specifications