Middle Atlantic MRK-2426 User Manual

• Fully welded construction

• 2,500 lb. weight capacity

• 1/8” thick structural steel internal braces

• 22” OD width with multiple depths available

• 1/2”, 3/4”, 1” & 1-1/2” electrical knockouts on rear plates top & bottom, easily
removable for cable pass-through, top plate additionally includes UHF/VHF knockouts

• Two wide pairs of 11-gauge, 10-32 threaded rackrail with numbered rackspace increments

• Keylocked solid rear door standard, optional vented rear door available

• Optional solid, fully vented, plexi and vented plexi front doors available

• Open top with configurable top panel options

• Durable black textured powder coat finish

• Seismic certified (when used with MRK-Z4 option) with an Ip value of 1.5

• UL Listed in the US and Canada

96-039 / rev 6b / 12-29-06 / MRK Series Enclosure

EIA compliant 19” gangable equipment rack shall be Middle Atlantic Products model #
MRK-__ (refer to chart). Overall dimensions shall be __”H x __”W x __”D (refer to
chart). Useable height shall be __ rackspaces, useable depth shall be __” (refer to
chart). Fully welded construction shall provide a 2,500 lb. weight capacity. Rack shall be
constructed of the following materials: top and bottom shall be 14-gauge steel,
horizontal braces shall be 16-gauge steel, rear door shall be 18-gauge steel and all
structural elements shall be finished in a durable black powder coat. Rack shall come
equipped with two pairs of 11-gauge steel rackrail with tapped 10-32 mounting holes in
universal EIA spacing, black e-coat finish and numbered rackspaces. The MRK shall have
a solid locking rear door. Rack shall have a removable rear knockout panel with 1/2”,
3/4”, 1” and 1-1/2” electrical knockouts and top BNC knockouts for UHF/VHF antennas.
Grounding and bonding stud shall be 1/4-20 threaded, installed in base of enclosure.
MRK Series enclosures shall satisfy the 1997 UBC and 2001 CBC Seismic Zone 4 and the
2000 IBC, 2003 IBC, 2002 ASCE Standard 7 and 2003 Ed. NFPA 5000 Seismic Use Group
III lateral force requirements for protecting 900 lbs. of essential equipment in upper
floor installations when used in conjunction with the MRK-Z4 seismic floor anchor
brackets with an Ip value of 1.5. Rack shall be OSHPD approved for fixed equipment
anchorage in California healthcare facilities. Rack shall be UL Listed in the US and
Canada. MRK enclosure shall be warrantied to be free from defects in material or
workmanship under normal use and conditions for the lifetime of the product.

OPTIONS

• Front doors shall be reinforced 16-gauge steel, model # FD-x (solid), VFD-x (vented,
22% open area), LVFD-x (vented, 63% open area), PFD-x (plexi), PVFD-44 (vented
plexi) (x = # of rackspaces)

• Vented rear doors shall be 16-gauge steel, model # MW-VRD-44 (vented top and
bottom), MW-LVRD-x (vented, 63% open area, excludes 24 and 37 space rack) (x = #
of rackspaces)

• Removable keylocked side panels shall be constructed of 16-gauge steel with recessed lift
handles, model # SPN-x-(267/312/36/423) (x = # of rackspaces), 267 = 26-1/2”
cabinet depth, 312 = 31-1/2” cabinet depth, 36 = 36” cabinet depth, 423 = 42”
cabinet depth

• Top panels shall be 16-gauge steel in four styles, model # MW-ST (solid), MW-10FT
(10” fan), MW-4FT (four 4-1/2” fans), MW-VT (vented), MW-LA (accepts 6” and 12”
wide cable ladders)

• Caster base shall add 1” to overall height, featuring four casters with a 1,300 lb. weight
capacity, UL Listed in the US and Canada. Model # CBS-MRK-x (x = cabinet depth)

• Fine floor friendly caster base shall have a 700 lb. weight capacity. Model #
CBS-MRK-xR (x = cabinet depth)

• Rail bracket adapters shall allow for mounting of panels vertically between rackrail
brackets. Available for 44 space enclosures. Model # RBA-MV44-x (x = 1, 2 or 3
rackspaces)

• Integrated fan tops with proportional speed thermostatic fan control shall include four
4-1/2” quiet fans, model # MW-4QFT-FC or one 10” fan, model # M-10FT-FC

• Additional rail kit, 11-gauge, 10-32 threaded, sold in pairs with hardware included shall
be MV-RRx (x = # of rackspaces)

• Seismic Zone-4 and Seismic Use Group III compliancy floor anchor kit shall be model #
MRK-Z4

• Slide-out AXS enclosure option available (See AXS Spec sheet # 96-055S)

96-039 / rev 6b / 12-29-06

Features

Enclosure Accessories
ADDITIONAL RAIL KIT
CASTER BASE
CONFIGURABLE TOPS
COPPER BUSS BAR
CRATING SERVICE
DOCUMENT POCKET
DOOR LATCH
GANGING HARDWARE
INNER PLATFORM BASE
LEVELING FEET
REMOVABLE SIDE PANELS
SEISMIC FLOOR ANCHOR BRACKETS
TOP RAILS
UNIVERSAL FRONT DOORS
VENTED REAR DOORS
WRINKLE TOUCH-UP PAINT

for details - see Master Catalog or
visit middleatlantic.com

The MRK Series 19” gangable enclosures
Narrow design for large multi-bay jobs

Architects’ and Engineers’ Specifications

MRK Series Enclosure

Engineered Mounting Solutions

US: New Jersey • California • Illinois • Voice: 973-839-1011 Fax: [phone] • middleatlantic.com

Canada: Ontario • British Columbia • Voice: 613-836-2501 Fax: [phone] • middleatlantic.ca

customizable specification clips available at middleatlantic.com

MRK-4426

middleatlantic.com

Middle Atlantic Products, Inc.

EIA/TIA Compliant

SEISMIC CERTIFIED

US: New Jersey • California • Illinois • Voice: 973-839-1011 Fax: [phone] • middleatlantic.com

Canada: Ontario • British Columbia • Voice: 613-836-2501 Fax: [phone] • middleatlantic.ca

MRK basic dimensions

A B C D

Overall Useable Overall Useable

Part # Height Height Depth Depth

MRK-4426 83.125” [2112] 77.125” [1959] 26.40” [671] 24.00” [610]
MRK-4026 76.125” [19341 70.125” [1781] 26.40” [671] 24.00” [610]
MRK-3726 70.875” [1800] 64.875” [1648] 26.40” [671] 24.00” [610]
MRK-2426 48.125” [1223] 42.125” [1070] 26.40” [671] 24.00” [610]
MRK-4431 83.125” [2112] 77.125” [1959] 31.40” [798] 29.00” [737]
MRK-4031 76.125” [1934] 70.125” [1781] 31.40” [798] 29.00” [737]
MRK-3731 70.875” [1800] 64.875” [1648] 31.40” [798] 29.00” [737]
MRK-2431 48.125” [1223] 42.125” [1070] 31.40” [798] 29.00” [737]
MRK-4436 83.125” [2112] 77.125” [1959] 36.00” [914] 33.60” [853]
MRK-4036 76.125” [1934] 70.125” [1781] 36.00” [914] 33.60” [853]
MRK-4442 83.125” [2112] 77.125” [1959] 42.00” [1067] 39.60” [1006]
MRK-4042 76.125” [1934] 70.125” [1781] 42.00” [1067] 39.60” [1006]

TOP VIEW OF MRK SIDE

SECTIONAL DETAIL

REAR VIEW TOP & BOTTOM

TOP VIEW

REAR VIEW

BOTTOM VIEW

SIDE VIEW

FRONT VIEW

rackrail to front
door clearance
(with rackrail in
forward-most
position)

2.227 [56.57]
solid/vented

2.04 [51.82]
plexi door

MRK-XX26=21.5 [546.1]
MRK-XX31=26.5 [673.1]
MRK-XX36=31.1 [789.9]
MRK-XX42=37.1 [942.3]

FLOOR MOUNTING LOCATIONS

Middle Atlantic Products, Inc.

1/4 - 20 X 1”

grounding stud

(1 place only)

18.88
[479]

2.19 [56]

3.28 [83]

22.00 [559]

1.72 [44]

2.19 [56]

5/8” [15.9] dia. KO
for UHF/VHF
antenna

1/2” [13] & 3/4” [19]
EKO

1” [25] & 1-1/2” [38]
EKO

removable EKO plates

1.50 [38]

2.13 [54]

8.41

[214]

C

D

max. rear

rail setback

1.56 [40]

C

22.88 [581]

19.50
[495]

22.00 [559]

19.25
[489]

2.07 [53]

17.13
[435]

2.45 [62]

Ø0.44 [Ø11] -

8x 0.79 [20]

19.88
[505]

.90 [23]

All dimensions in inches unless otherwise noted [All dimensions in brackets are in millimeters]

A

B

MRK-XX26=24.29 [617]
MRK-XX31=29.29 [744]
MRK-XX36=33.89 [860.8]
MRK-XX42=39.89 [1013]

Middle Atlantic Products, Inc.

3.00 [76]

2.07 [53]

FRONTREAR

front rail setback

1.50 [38]

MRK top options

removable plate opening

accommodates 2 space panel

MW-10FT MW-4FT MW-ST MW-VT

removable plate removable plate

laser knockouts

configurable -1 to 4

4-1/2” fans

removable plate

(

)

removable plate

opening for

10” fan

MW-LA

17.50

[444.5]

14.125
[358.8]

accommodates 12” and 6”

width cable ladders

17.75

[450]