Middle Atlantic ERK40SPREAR EXT3in. in. D - ERK-40-R-EXT3

Middle Atlantic ERK-40-R-EXT3 40U Rear Door Extender Bay

Overview

The Middle Atlantic ERK-40-R-EXT3 is a 40U rear door extender bay that adds 3 inches of usable depth to ERK series open-frame racks — the right answer when rear-mounted gear (cable managers, brush panels, PDU arms, or deep patch management hardware) pushes past the standard footprint. If you've ever lost the last inch of clearance behind a patch bay or had a PDU bracket fighting for space inside a rack column, this is the targeted fix.

At 75.86 inches tall and 23 inches wide, the ERK-40-R-EXT3 spans the full 40U height of the ERK column. The included rear door closes off the rear of the extended bay cleanly, which matters both for airflow management and for keeping rear cable runs protected in open telecom or security head-end rooms. Finish is black, consistent with Middle Atlantic's ERK rack family aesthetics.

Seismic rating is standard on this unit — relevant for deployments in California, Pacific Northwest facilities, or any site operating under IBC or OSHPD seismic compliance requirements. If your project specs call out seismic-rated rack infrastructure, the ERK-40-R-EXT3 covers that requirement without needing an aftermarket brace or separate certification document for the extension.

Key Features

• 3-Inch Depth Extension (40U Height): adds exactly 3 in (7.6 cm) of rear clearance across the full 40U column — enough to accommodate rear PDU arms, cable management bars, or deep keystone patch panels that would otherwise interfere with door closure or airflow baffles behind the rack.
• Integrated Rear Door: the rear door ships as part of the unit, so you don't need to source a separate door kit after install. This closes off the extended bay and maintains a consistent rear face on the rack assembly — important in shared equipment rooms where aesthetics and cable protection both matter.
• No Front Door: front of the extension is open, which keeps front-access workflow unobstructed. If you need front door coverage you'll handle that at the base ERK enclosure — the ERK-40-R-EXT3 is rear-depth-only by design.
• Seismic Rated: qualifies for seismic-compliance installations without add-on hardware. For healthcare, education, government, or West Coast commercial deployments where the structural spec sheet matters, this rating is on the unit itself — not an aftermarket modification.
• Black Finish: matches the standard ERK series finish directly. In mixed-rack environments or glass-door server rooms, consistent finish matters for professional presentation and audit-ready installations.
• 37 lb Shipping Weight: the unit ships at 37 lbs (16.8 kg) — plan for two-person handling during installation, particularly when fitting into an already-populated rack room with limited floor space around the column.
• Compatible with ERK Base Series: designed specifically for the ERK rack family. This is not a universal depth extender — it's engineered to mate with ERK series columns, which means fit and finish are precise and no field modification is required at install.

Integration & Compatibility

The ERK-40-R-EXT3 is built for the Middle Atlantic ERK rack series and is not cross-compatible with other rack families without verification. Before ordering, confirm your base rack is an ERK series column — the extender mates to ERK-specific mounting points and column geometry.

This unit is particularly useful in open-frame rack enclosures deployed in security head-end rooms, telecom closets, and AV equipment bays where rear cable density is high. In surveillance infrastructure specifically, head-end racks housing NVRs, PoE switches, and patch panels often accumulate significant rear cable depth — the 3-inch extension prevents rear equipment from pressing against door hardware or restricting airflow at the back of the rack.

If you are sizing power distribution for a head-end rack, consider pairing this extender with appropriate rack PDU solutions that mount in the newly created rear depth. For structured cabling behind the rack, rack cable management accessories from the same ERK ecosystem will align correctly with the extended bay dimensions.

For projects requiring full enclosure planning, reviewing a rack enclosure planning guide before finalizing depth requirements helps prevent the need for field modifications after equipment is racked.

Frequently Asked Questions

Q: What rack series is the ERK-40-R-EXT3 compatible with?

A: The ERK-40-R-EXT3 is designed specifically for Middle Atlantic's ERK base series rack columns. It is not a universal extender — confirm your base rack is ERK series before ordering.

Q: Does the ERK-40-R-EXT3 include a rear door?

A: Yes. The unit includes a rear door as part of the assembly. There is no front door — the front of the extension remains open.

Q: Is the ERK-40-R-EXT3 seismic rated?

A: Yes, the ERK-40-R-EXT3 is seismic rated, making it suitable for installations subject to IBC or similar seismic compliance requirements.

Q: How many rack units does the ERK-40-R-EXT3 span?

A: It spans 40 rack units (RU), matching the full height of a 40U ERK series rack column at 75.86 inches (192.7 cm).

Q: What is the exact depth added by the ERK-40-R-EXT3?

A: The extender adds exactly 3 inches (7.6 cm) of depth to the rear of the ERK rack column.

Q: What is the shipping weight of the ERK-40-R-EXT3?

A: The unit ships at 37 lbs (16.8 kg). Plan for two-person handling during installation.

Marty Allison

I specify the ERK-40-R-EXT3 on head-end rack builds where rear cable density is the design constraint — specifically the 3-inch depth gain across the full 40U column height is what makes this a targeted solution rather than a workaround. On a populated ERK rack running NVRs, managed PoE switches, and a patch field, you can easily exhaust rear clearance before you run out of rack units, and this extender closes that gap cleanly without rebuilding the rack assembly.

Technical Highlights:

• 3 in (7.6 cm) Depth Extension: enough rear clearance for PDU arm brackets, horizontal cable managers, or deep keystone patch modules that would otherwise prevent proper rear door closure or restrict exhaust airflow paths.
• Seismic Rating: this is not a retroactive add-on — seismic compliance is built into the ERK-40-R-EXT3 as delivered, which satisfies seismic infrastructure requirements in regulated environments without a separate engineering sign-off on the extension hardware.
• Integrated Rear Door at 40U: the door is included and spans the full 75.86 in column height, so the rear of the extended bay is closed and consistent — no exposed rear cable runs, no gap between the extender and the base enclosure's rear face.

Deployment Considerations:

• The ERK-40-R-EXT3 is ERK-series specific — verify the base rack model before it ships to the job site. Installing on a non-ERK column will require field modification that voids the engineered fit.
• At 37 lbs shipping weight, this is a two-person lift for overhead or elevated rack positions. Plan install sequence so the extender goes on before the rack is fully populated — adding it after equipment is installed in a tight room is a more difficult job.

For security head-end rooms and telecom closets where a 40U ERK rack is the backbone of the infrastructure and rear depth is the binding constraint — particularly on NVR/switch/patch-heavy builds in healthcare or education facilities with seismic requirements — the ERK-40-R-EXT3 is the correct part.