Modular enclosure baying checklist before you order

Specify the complete joined assembly before ordering individual bays. Matching height and depth do not establish compatible joints, a sealed perimeter, or coordinated door access. You need documented interfaces, joint hardware, end closures, bonding provisions, and a disconnect arrangement that covers every affected door.

Treat baying as an assembly design, not a fastening accessory. The checks below define what needs approval before fabrication, wiring, and installation begin. They do not assume that separate enclosures can become a modular system simply by removing their sidewalls.

Confirm the bay arrangement

Start with an elevation drawing showing the entire lineup, including doors, exposed ends, and the intended disconnect location. Mark the viewing direction so left and right remain unambiguous throughout the drawing package.

• Identify each position as an end bay, intermediate bay, or disconnect bay using the proposed system's terminology.
• Record each bay's width, height, depth, door swing, and joint orientation.
• Confirm which sides are open and which require permanent exterior panels.
• Obtain written confirmation that the exact frames, joining interfaces, and accessories are compatible.
• Confirm whether the assembly must be joined before internal equipment is installed.
• Check the complete lineup against delivery openings, lifting access, and the installation route.

For example, a three-bay straight lineup has two bay-to-bay interfaces and two exposed outer ends. That describes the arrangement, not the required hardware quantity. Each interface may require several fasteners, separate seals, or additional structural parts.

Do not substitute a conventional enclosure with a sidewall cut away. Removing that wall can change stiffness, sealing, and the basis of its rating.

Match the joint hardware and sealing system

The joint needs a defined load path and a continuous seal. Bolts that pull two frames together do not establish either requirement by themselves.

• Specify the exact joining kit or documented interface drawing for each joint.
• Identify fastener material, thread, length, quantity, tightening sequence, and required torque from the system documentation.
• Confirm gasket material, profile, location, corner treatment, and intended compression.
• Identify compression stops or other features that prevent excessive gasket crushing, where the design uses them.
• Include filler plates, joint covers, and closures required around recessed frame features.
• Confirm whether joint gaskets are replaceable after assembly and whether separation requires new seals.
• Keep sealant out of the specification unless the documented joint design calls for it.

Do not choose gasket thickness to compensate for misaligned frames. Correct alignment and support first; excessive tightening can distort the sealing surfaces.

For material and compression fundamentals, use the guide to foam or rubber enclosure door gaskets. A bay joint still needs its own documented seal design; a suitable door gasket is not automatically suitable there.

Keep the rating tied to the complete assembly

NEMA type ratings are manufacturer ratings; our enclosures are not UL listed. For a modular lineup, request documentation covering the exact assembled configuration, not only the individual bay frames.

• State the required enclosure type and whether the project separately requires third-party listing.
• Describe indoor or outdoor exposure, airborne dust, hose-directed water, cleaning chemicals, and corrosion conditions.
• Include all end panels, joint covers, roofs, plinth interfaces, and entry plates in the assembly review.
• Confirm which mounting orientations and joining arrangements the documented rating covers.
• Identify every field modification and obtain approval before cutting or drilling.
• Specify the inspection and verification required after assembly, using the system documentation and project requirements.

Water protection depends on the entire boundary. A properly sealed bay joint cannot compensate for an unsuitable end panel or cable entry.

The same assembly-level limitation applies to devices mounted through the enclosure wall. See what enclosure rating remains after mounting devices when coordinating entries, controls, and cooling equipment.

A joint rating also does not establish chemical compatibility. Record the cleaning chemical, concentration, temperature, and exposure method rather than specifying only “washdown.”

Reserve wiring and subpanel access

Overall lineup width is not continuous usable mounting space. Frames, joint fasteners, disconnect mechanisms, and cable passages can interrupt the interior.

• Obtain usable mounting-panel dimensions and panel-to-door clearance for each bay.
• Show the joint frame envelope on the internal layout, including bolt heads and installation-tool access.
• Confirm whether mounting panels can be installed or removed after adjacent bays are joined.
• Identify any split panels, joining supports, or removable rails required by the documented system.
• Reserve cross-bay wireways and protect conductors at frame openings.
• Check conductor bending space at terminals and clearance around disconnect operating mechanisms.
• Separate power, control, and communications wiring as required by the equipment instructions and electrical design.
• Calculate heat loss and check airflow paths across each bay rather than assuming uniform internal temperature.

Use the backplate and DIN rail layout guide for component spacing and wiring fundamentals. The baying drawing should then show what the joint removes from that usable area.

Keep routine service items accessible without dismantling neighboring equipment. A removable panel is not practically removable if its extraction path is blocked by cross-bay wiring.

Coordinate disconnects and every door

A disconnect in one bay does not automatically isolate every circuit in the lineup. Door interlocks also do not establish that exposed parts are de-energized.

• Mark the disconnect location, operating-handle position, and every door associated with its interlock arrangement.
• Request a documented compatibility review for the disconnect, operating mechanism, linkage, and door hardware.
• Define the permitted opening and closing sequence for all affected doors.
• Confirm that linkage travel and alignment remain correct across the full assembled lineup.
• Identify incoming supply terminals, separately supplied controls, stored energy, and any other sources that remain hazardous after opening the main disconnect.
• Document isolation points, required barriers, warnings, and the procedure for controlling all energy sources.
• Require qualified verification of interlock operation before energization and after adjustments affecting alignment.

Do not assume that an access interlock is a safety-rated function. Any required safety function needs an appropriate design and validation for the machine and its risks.

Interlocks do not replace lockout/tagout or verification of absence of voltage. Do not accept a layout that requires bypassing an interlock for routine operation.

Plan bonding and structural support

Mechanical joining and protective bonding are separate design requirements. Gasketed joints, coatings, and removable panels can interrupt electrical continuity.

• Obtain the documented bonding arrangement between frames, exterior panels, doors, and mounting panels.
• Identify dedicated bonding points and any bonding jumpers required across joints.
• Do not rely on ordinary joint bolts as the protective bonding path without supporting design documentation.
• Verify protective bonding continuity using the applicable inspection procedure before energization.
• Record equipment mass by bay, including mounting panels, transformers, drives, and supported cable loads.
• Confirm lifting provisions for the actual assembly and loading condition.
• Coordinate base alignment, floor level, anchor locations, and support beneath the joined frames.

The grounding and bonding guide explains the fault-current path. The assembly drawings must identify how that path continues through the complete lineup.

For anchoring details, use mounting a freestanding enclosure to the floor. Bay joints do not replace floor anchors, and anchors should not pull a twisted lineup into alignment.

Send a complete quote package

Send one coordinated drawing package rather than separate enclosure descriptions. Include the electrical and mechanical requirements that determine whether the proposed arrangement is suitable.

• Arrangement: Dimensioned front, side, and plan views; bay identifiers; joint locations; exposed ends; door swings; installation access.
• Environment: Required enclosure type, listing requirement, ambient temperature, water exposure, corrosion conditions, and cleaning chemicals.
• Construction: Material, finish, joint interfaces, joining hardware, gasket requirements, end closures, and base arrangement.
• Interior: Equipment layout, usable panel dimensions, equipment mass, heat losses, cable passages, and service-removal paths.
• Electrical access: Disconnect details, interlock sequence, barriers, additional energy sources, bonding provisions, and required labels.
• Responsibilities: Who assembles the lineup, who verifies sealing and bonding, and who approves the completed electrical assembly.

We build custom enclosures with customer-defined material, dimensions, and cutouts, starting from one piece. That capability does not establish compatibility with a modular bay system. Request application review before treating any custom enclosure as a joined bay or accepting a modular assembly requirement.

If the layout does not actually require joined bays, use the enclosure selector to compare usable dimensions and listing requirements for an individual enclosure. Check thermal suitability separately before releasing the order.

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