Installation

If liquids such as moisture, chemicals, and condensation contact the electronics, circuit breaker, fuses, bussing, or other electrical components, do not attempt to clean or repair the equipment as this may lead to unrepairable damage. If the equipment is energized, de-energize it. If equipment is not energized, do not energize it. Contact the Schneider Electric Customer Care Center at 888-778-2733.

The weight of the average complete switchgear unit is 2500–2900 lb. (1134–1315 kg) for up to 50 kA and 3200 lb. (1451 kg) for 63 kA. Refer to Switchgear and Component Weights and Individual Components to determine switchgear and component weights for handling and structural considerations.

The switchgear is designed for installation on a concrete pad. Refer to the factory order drawings for any additional mounting details which may be required on specific orders. The pad must be flat and leveled to 0.06 in. (1.6 mm) per square yard to help ensure proper alignment and to help prevent distortion of the gear.

Provide a seven ft. (2.1 m) wide aisle space in front of the mounting pad, flush with and finished to the same tolerance as the mounting pad. This level surface is necessary for the circuit breaker lift truck and for inserting the circuit breakers into the bottom compartment.

Floor Plan for Switchgear Rated Up to 50 kA

Masterclad Extended Floor Plan for 63 kA-Rated Switchgear

Stub conduits a maximum of one inch. (25 mm) above floor level. To simplify moving the switchgear into place, keep the conduit flush with the surface of the floor. Position the conduit accurately so that there is no mechanical interference with the assembly frame. Eliminate continuous loops of reinforcing rod or structural steel that do not enclose all conductors of the same circuit. Floor Plan for Switchgear Rated Up to 50 kA and Masterclad Extended Floor Plan for 63 kA-Rated Switchgear illustrate typical floor plans. Refer to the customer order drawings before using the typical foundation specifications. Customer order drawings are created to comply with specific customer requirements and therefore supersede the information provided here.

1. The switchgear may be shipped in one or more shipping sections. Review the assembly drawings to verify that switchgear sections will be assembled in the correct order.

2. Verify that the conduit placement on the foundation is accurate according to customer drawings. Error in conduit placement may prohibit the proper installation of switchgear as described in this section (see the note below).

3. Sweep the pad and remove debris before installing any sections.

1. Move the sections, with skids attached, into place. Install the shipping section that allows the most maneuverability first. If rollers must be used, move with the skid in place. Remove the skid only when the switchgear is in proper position on the pad. Lower the first section onto the pad. Do not pry directly on the structure, doors, or covers.

2. Before proceeding, verify:

   • The conduits are in the center of the cutouts.

   • The back of the unit is perpendicular to the pad and has proper clearance.

   • The mounting holes line up with the mounting channels.

3. Move an adjacent switchgear shipping section into place.

4. Level each section before installing the next. Install steel shims, when necessary, between floor channels and switchgear.

5. Verify that the switchgear sections are level, aligned, and fit snugly together. If the sections do not fit properly, lift the most recently placed section by crane, remove any obstructions, and re-install.

6. Bolt switchgear shipping sections together.

   NOTE: All shipping sections must be bolted together in place before bolting them to the channel sills or installing the horizontal main bus.
7. Repeat steps 4–5 for additional switchgear shipping sections.
8. Verify that all switchgear shipping sections are in the correct position according to the job drawing after all sections are bolted together.

9. Install all cable compartment floor plates to create a barrier between cable compartment and space below the switchgear.

3000 A sections with auxiliaries on the top have the two rear bolt locations covered by a ventilation duct. In order to access those two locations, the two screws holding the ventilation boxes on left and right side need to be removed. Then the entire ventilation duct can be slid forward to access the anchor points. Replace the duct to its original position once the switchgear is bolted or welded.

Access to Rear Bolt Locations in Auxiliary-3000 A Sections

Install the main bus at the shipping split only after all sections are securely anchored in place and no additional movement of the assembly occurs. Bus bar extensions for shipping splits are shipped with the miscellaneous items.

A typical main bus assembly is shown in (see Main Bus Assembly). The side and rear views (see Main Bus Assembly) of the assembly show the general arrangement of the main bus and riser. The side (see Main Bus Connections-Side View) and top (see Main Bus Connections-Top View) views show the different bus connections and the orientation of the filler and splice plates. When aluminum bus is furnished, some of the circuit breaker connections and splice or filler plates are copper.

Main Bus Assembly

Main Bus Connections-Side View

Main Bus Connections-Top View

The standard switchgear is furnished with fiberglass-polyester bus barriers between bays. Porcelain “pass-throughs” are available as an option for 50 kA and below only.

Main Bus Pass-Through, Porcelain—Optional for 50 kA and Below Only

For porcelain pass-throughs only, O-rings must be installed inside the passthroughs to cushion the bus bars under short-circuit conditions.

Schneider Electric recommends the following installation steps for installing two bus bars:

1. Place the larger O-ring around both bars at the correct distance from the end, and the smaller rings around each bar approximately one inch (25 mm) on each side from the large O-ring.

2. Slide both bars into the porcelain (one end of the porcelain may have a larger opening).

   NOTE: When bus bar stand-off insulator installation is required on shipping sections, fiberglass/polyester washers and rubber O-rings must be installed as shown.

   Stand-Off Bus Support

   

3. Remove the main bus covers and the insulating boots.

4. Install one phase at a time by sliding the bus bar through the bus barriers and loosely bolting the horizontal bus to the vertical bus. Do not bend or force the bus to make this connection. The through bushings and the divided insulating barrier may be loosened if necessary. They have sufficient clearance and adjustment to compensate for minor field misalignment of shipping sections.

5. Tighten the bolts holding the bus bar joints only after all three bus bars are in place and properly fitted. Use a torque wrench to make sure that the bolts for bus bar connections are tightened in accordance with recommended bolt torque values.

6. Reinstall all boots ensuring they are properly closed.

Consult the customer wiring diagram for reconnection of wiring at the shipping break. Each wire is identified and has been previously connected during assembly and verified at the factory. If the identification is missing or blurred, ring-out before connecting to avoid control circuit and instrument panel problems at start-up.

Follow these instructions for the initial install of the circuit breaker:

1. De-energize all primary and control power circuits.

2. Insert each circuit breaker into the connected position of its respective circuit breaker compartment. Observe the operation of the ground contacts, shutters, and disconnect position latch.

3. Remove each circuit breaker from its compartment. Open the shutters and check that tracks made in the contact grease by the fingers of the main disconnects extend back a minimum of 0.5 inch (13 mm) from the front edge of each bar. Make sure that the ground shoe leaves tracks on the ground bus.

Do not force circuit breakers into circuit breaker compartments. Compartment rating interlocks help prevent inserting circuit breakers into incorrect sections.

1. Withdraw the drawout control power fuse drawer and the drawout voltage transformer drawer. Observe their operation. Verify that the static grounding contacts touch the moving drawout contacts and that the primary and secondary contacts make proper contact.

2. Prior to energization, verify spacing of all VT, CPT and fuse drawout cabling.

   The VT Cables are designed to run parallel and perpendicular to the barriers across their length in the cubicle. They are positioned and spaced correctly (from phase and ground) by the porcelain.

3. Verify the cables are routed properly and the porcelain bushings are not displaced from their designed location. Visually inspect for any damage to the insulation or accumulation of dust on the cable on both sides of the barrier.

   Examples of Cable Breakers

   
4. If there is any visible sign of damage, replace the cables. Clean possible dust accumulation with a lint free cloth and denatured alcohol. Two types of cable pass through insulators are used within Masterclad, a porcelain bushing and a nylon cable gland. The cable gland was introduced to the assemblies in 2021. If the equipment contains nylon cable glands to route cables, disregard the information pertaining to porcelain bushings.

5. Make sure that all the VT cables pass freely through the porcelain bushings without stressing their placement in the barrier.

6. The bushings cannot tilt or displace because of interference with the cables. If needed, reshape the cables so that their axes match the axes of the bushing bores.

7. Make sure the O-rings are firmly in place in their mounting grooves.

O-rings and Mounting Grooves

In general, the cables must always maintain the following minimum clearances:

For additional information on proper field installation of customer cabled transformer connections, refer to document 46010-520.

Before making external power connections, perform a high-potential (hi-pot) dielectric withstand test on the bus and circuit breakers as an assembly.

Use a reliable transformer-type tester with a built-in voltmeter and milliamp meter for hi-pot testing. Capacitor loaded bench-type testers with neon bulb indicators do not have sufficient capacity to give reliable results.

In accordance with NEMA standards, all bus within the switchgear is phased A-B-C left to right, top to bottom, and front to back when viewing the assembly from the front (the circuit breaker compartment side). If, for any reason, the bus must be phased differently, the different phases are identified on the bus with a label.

The equipment enclosure provides anchorage tie-down points to accept anchor attachments to the building structure or foundation. Masterclad 5-15 kV Metal-Clad indoor enclosures provide enclosure base frame clearance holes to accept bolted anchorage attachments as shown in Non-seismic Switchgear Anchor Assembly. Four anchors are required for each section, two in the front and two in the rear located per the Floor Plan for Switchgear Rated Up to 50 kA and Masterclad Extended Floor Plan for 63 kA-Rated Switchgear.

Non-seismic Switchgear Anchor Assembly