Quick Tray Application Guide - Hoffman
®
Quick Tray Application Guide
Quick Tray Wire Mesh Cable Tray Application Guide
Table of Contents Components . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2 Quick Tray Wire Mesh Cable Tray Bolt Cutter and Connectors Cutting the Cable Tray . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4 Creating a 90 Degree Bend . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6 Creating a Large Radius Bend . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8 Creating an Elbow . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10 Creating a 90 Degree Tee . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12 Creating a Y Junction Tee . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .13 Reducing Quick Tray Width . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .14 Changing Levels . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .15 Quick Tray Fill and Load Calculations . . . . . . . . . . . . . . . . . . . . . . . . . . .16 National Electrical Code References . . . . . . . . . . . . . . . . . . . . . . . . . . .18 Quick Tray Catalog Number Reference Guide . . . . . . . . . . . . . . . . . . . .20
Data subject to change without notice
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1
Components Quick Tray Wire Mesh Cable Tray The Quick Tray Wire Mesh Cable Tray comes in straight 10 ft. sections that are easily modfied and combined to fit almost any configuration. • Smooth, round wires minimize dust buildup and cable snagging. • Zinc plating resists corrosion. • Large 2 x 4 in. (51 x 102mm) mesh allows cable to be routed into and out of the tray at any point without cutting the tray • Available with either 2 or 4 in (51 or 102mm) sidewalls to hold cable in the tray and in a variety of widths to accommodate different numbers of cables Different cable tray sizes can be joined using the techniques described in this manual to make a truly custom installation using standard parts.
Catalog Number
Width in.
QT2X2
2
51
2
51
QT2X4
4
102
2
51
QT2X6
6
152
2
51
QT2X8
8
203
2
51
QT2X12
12
305
2
51
QT2X16
16
406
2
51
QT2X18
18
457
2
51
QT2X20
20
508
2
51
QT2X24
24
610
2
51
QT4X4
4
102
4
102
QT4X8
8
203
4
102
QT4X12
12
305
4
102
QT4X16
16
406
4
102
QT4X18
18
457
4
102
QT4X20
20
508
4
102
QT4X24
24
610
4
102
2
Depth in. mm
mm
Data subject to change without notice
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Components Bolt Cutter and Connectors Sturdy side action bolt cutter is specially designed to provide a flush cut and help create a protective coating for the new cut.
DataCom Products
Bolt Cutter
Catalog Number
Description
QTBC
Side Action Bolt Cutter
Catalog Number
Description
Pkg. Qty.
QTBN1
1/4 in. round head screws with flange nuts
50
QTSSW1
1 in. (25mm) square splice washer
50
QTSSW2
1 1/2 in. (38mm) square splice washer
50
QTSSW3
2 in. (51mm) square splice washer
25
Connectors Splice Washers
Splice Washers are used with QTBN1 screws and flange nuts for bolting turns, bends, and tees; connecting tray sections; and fastening splice bars.
Splice Plate and Connection Tool
Splice Plate quickly connects tray sections. Made of zinc-coated steel. Requires special installation tool, included with each package and available separately.
Description
Pkg. Qty.
QTFS
Splice Platea
50
QTFST Splice Plate Connection Tool a Includes one QTFST Splice Plate Connection Tool
Splice Bars
Splice Bars provide extra support and stability to tray sides when connecting tray sections with splice washers. Universal bars can be cut to fit with bolt cutters and bent for use in tees and elbows. Made of zinc-coated steel. Requires QTSSW1 1 in. (25mm) Square Splice Washers and QTBN1 Screws and Flange Nuts to fasten to side of tray. Data subject to change without notice
Catalog Number
☎
1
Catalog Number
Description
QTTS
T Connection Splice Bar
50
QTUS10
10 in. (254mm) Universal Splice Bar
50
QTUS43
43 in. (1092mm) Universal Splice Bar
1
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Pkg. Qty.
3
Cutting the Tray Always use the Hoffman side action bolt cutter to cut the Quick Tray Wire Mesh Cable Tray. This cutter allows precision cuts that minimize sharp edges that could snag wire. Its action also helps to protect the new cut from corrosion. Decide which wires must be cut When cutting for a bend, always review the cutting pattern for the tray size and desired bend before cutting. Red areas on the drawings should be removed.
Cut the first side wire Starting with the top side wire, position the cutting jaws on the cradle wire. Make the cut at an angle away from the new end.
4
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Cutting the Tray Cut the remaining side wires Cut the remaining side wires, remembering to rest the cutting jaws on the cradle wire and cut at an angle away from the new end. Make one clean cut to eliminate grinding or touch-up.
Cut the bottom wires Turn the tray over and cut the bottom wires from the underside. Always rest the cutting jaws on the cradle wire and cut at an angle away from the new end. Make one clean cut to eliminate grinding or touch-up.
Cut from the outside wires to the inside
That’s it! The cable tray is now ready for installation or for bending to the desired shape. Data subject to change without notice
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Creating a 90° Bend At the desired bend location, cut the wires shown in red for the width of the cable tray. Cut the side, then the bottom wires Cut all the side wires at the bend location for the tray size.
6
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Creating a 90° Bend Bend the cable tray Turn the tray on the uncut side. Smoothly bend the tray up until the inside edges closest to the uncut side meet.The bend radius should be 5 in. (120mm).The table shows the outer bend size for selected sizes.
Width of Tray in. mm
Size in.
mm
4
102
15
375
6
152
17
430
8
203
17
430
12
305
21
530
18
457
25
630
24
610
29
730
Secure the bend Fasten at the location shown with QTBN1 screws and flange nuts and the splice washers indicated for the tray width. 4 in./ 102mm
2 in./ 51mm
6 to 24 in./ 152 to 610mm
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7
Creating a Large Radius Bend Large radius bends are formed by removing the outside and bottom wires at the bend location.
Cut the side and bottom wires Remove the wires from the outside and the bottom of every other mesh section at the location of the bend. Follow the cutting pattern shown for the size tray.
8
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Creating a Large Radius Bend Bend the cable tray Lay the tray on a flat surface and pull the ends on the uncut side towards each other until the remaining cut sides almost touch at the corners.
Assemble the bends Fasten the inside of the bends together with the hardware shown in the drawings and in the table. A and B assemblies, where used, can be in any sequence on the inside of the bend.
2 in./ 51mm
Data subject to change without notice
4 to 24 in./ 102 to 610mm
☎
Width of Tray in. mm
Assembly Qty. A B
Radius in. mm
Size in.
mm
4
102
0
3
9
229
20
508
6
152
0
4
11
279
26
660
8
203
2
2
11
279
26
660
12
305
4
2
17
432
35
889
16
406
6
2
18
457
42
1067
18
457
9
0
28
711
51
1295
20
508
0
9
28
711
51
1295
24
610
1
10
28
711
54
1372
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Creating an Elbow Two cable trays can be joined to create elbows at various angles. Cut side wires from each tray Follow the cutting pattern for the tray width, removing the portions shown in red.
16 in./ 406mm
4 in./ 102mm
18 in./ 457mm 6 in./ 152mm
20 in./ 508mm 8 in./ 203mm
24 in./ 610mm
12 in./ 203mm
10
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Creating an Elbow Align the wires of the two trays at the desired angle Fasten the tray as shown. Use two QTBN1 screws and flange nuts and the splice washers indicated for the tray size for each joint. To form an adjustable angle, use one QTBN1 screw and flange nut and the splice washers indicated for the tray size, centered as shown under Adjustable Elbows. Be sure each splice washer is over two tray bottom wires.
Tray Width 4 in./ 102mm
Tray Width 8 to 18 in./ 203 to 457mm
Tray Width 6 in./ 152mm
Adjustable Elbows
Data subject to change without notice
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Creating a 90° Tee The T-connection splice bar connects the two sections of Quick Tray Wire Mesh Cable Tray to form a 90° tee. Cut the side wires Cut the side wires from the tray forming the top of the tee as shown in the cutting guide for the size tray.
Connect the cable trays Use two 10 in. Universal Splice Bars, bent in the middle to 90°, or two T Connection Splice Bars to connect the trays. If using T Connection Splice Bars, always put the long side parallel to the widest tray, or the one planned to carry the heaviest load.
T Connection Splice Bars
Universal Splice Bars
12
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Creating a Y-Junction Tee The Y-Junction tee requires cutting both sections of Quick Tray Wire Mesh Cable Tray. Cut both tray sections Cut and remove the wires indicated for the size tray.
Bend side wires to 45°
Connect the tray sections Form the Y by connecting the side wires of the two trays as shown.The universal connectors must be cut to 3 in. Also connect the trays with splice washers and QTBN1 screws and flange nuts. Use one on 4 and 6 in. trays, two on 8 and 12 in. trays, and three on 16 in. and wider trays.
Data subject to change without notice
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Reducing Quick Tray Width Reduce Quick Tray Wire Mesh Cable Tray width to connect to smaller tray by cutting side and bottom wires. Cut the side and bottom wires Cut the wires shown in the cutting guides to make a four inch or eight inch reduction in tray width.
4 in./102mm Reduction
Connect the uncut side of the trays Use a QTUS10 Universal Splice Bar with fasteners shown.
Bend the cut wires of each tray Use a QTUS10 Universal Splice Bar with fasteners on each pair of tray wires.
14
Data subject to change without notice
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8 in./203mm Reduction
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Changing Levels Quick Tray Wire Mesh Cable Tray is easily formed to go around obstacles by removing side wires and bending to the desired angle. Remove side wire sections Remove every other side wire section at the bend location from both sides of the tray.The number of side wire sections removed determines the radius of the bend.
Bend the tray Bend the tray smoothly up or down to go around the obstruction.
Data subject to change without notice
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Quick Tray Fill and Load Calculations The folllowing tables and formulas are provided to help determine how many cables can be safely carried by each size wire mesh cable tray tray and to determine the appropriate distance between supports for the load, based on number of cables, cable tray size, and bracket type. Wire Mesh Cable Tray Fill Ratio
Use the following formula to calculate the number of cables that will result in a particular fill ratio, where:
Fill ratio = Cross section of cable Cross section of tray
A = Inside tray area, in in.2 D = Cable diameter, in inches
According to NEC 392.9 (B), when using ventilated tray with multiconductor control cable, the sum of the crosssectional areas shall not exceed 50 percent of the interior cross section of the tray.
F = Fill ratio in %
The Quick Tray Wire Mesh Cable Tray Fill Table below shows the number of cables and the load in lbf/lineal foot developed by typical 4 pair and 6 pair cable weighing 20 lb/kft and 40 lb/kft, respectively.While this table is a useful guide, actual loads must be calculated using the cable specified.
N=
N = Number of cables The formula is F ( 100 ) * ( [(D/2)A2 * Π])
EXAMPLE: The installation will use CAT cable at .19 in. diameter, 20 lb per 1000 ft2.The desired fill ratio is 40%.The wire mesh cable tray tray is 2 in. (51mm) high by 2 in. (51mm) wide. A = 3.5 in.2 D = .19 in. F = 40% N=
40 3.5 ( 100 ) * ( [(.19/2) 2 * Π])
= 49 cables
Load/foot = 49 cables * 20 lb = 0.98 lb/ft 1000 ft.
Quick Tray Wire Mesh Cable Tray Fill Table at 50% Fill Catalog Number
Height in.
Width in.
Area in.2
CAT Cab Type (4 pair), .19 in. diameter, 20 lb/kft No. Cables Load at 50% Fill lbf/lineal ft
CAT Cab Type (6 pair), .26 in. diameter, 40 lb/kft No. Cables Load at 50% Fill lbf/lineal ft
QT2X2
2
1.75
3.5
62
1.24
32
1.28
QT2X4
2
3.75
7.5
133
2.66
70
2.8
QT2X6
2
5.5
11
195
3.9
103
4.12
QT2X8
2
7.5
15
266
5.32
141
5.64
QT2X12
2
11.5
23
408
8.16
216
8.64
QT2X16
2
15.5
31
550
11
291
11.64
QT2X18
2
17.5
35
621
12.42
329
13.16
QT2X20
2
19.5
39
692
13.84
367
14.68
QT2X24
2
23.5
47
834
16.68
442
17.68
QT4X4
4
3.75
15
266
5.32
141
5.64
QT4X8
4
7.5
30
532
10.64
282
11.28
QT4X12
4
11.5
46
816
16.32
433
17.32
QT4X16
4
15.5
62
1100
22
583
23.32
QT4X18
4
17.5
70
1242
24.84
659
26.36
QT4X20
4
19.5
78
1384
27.68
734
29.36
QT4X24
4
23.5
94
1668
33.36
885
35.4
16
Data subject to change without notice
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Quick Tray Fill and Load Calculations Supporting Quick Tray Wire Mesh Cable Tray The Quick Tray Wire Mesh Cable Tray is sized based on the number and type of cables required for the current and future need. A 50% fill ratio should equal the maximum number of cables pulled in a given cross section. Straight section supports installed at 5-foot (1.5m) centers are typical. For support spans greater than 5 feet (1.5m), cable loads must be evaluated to ensure that the span between the supports is suitable for the load.The support and Cable Tray Catalog Number
Maximum Load in lb/ft According to Span 5 ft 6 ft 7 ft 8 ft
9 ft
10 ft
QT2X2
17.17
12.54
7.51
6.04
4.77
3.86
QT2X4
18.10
14.00
11.30
9.30
7.40
5.10
QT2X6
25.10
19.80
16.00
13.40
11.00
9.00
QT2X8
25.10
19.80
16.00
13.40
11.00
9.00
QT2X12
36.00
27.70
22.10
18.10
14.60
10.50
QT2X18
65.00
45.50
33.80
26.10
19.40
15.00
QT2X20
65.00
45.50
33.80
26.10
19.40
15.00
QT2X24
67.00
48.70
37.80
30.30
23.70
17.00
QT4X8
43.80
35.90
30.10
25.40
21.20
17.00
QT4X12
57.95
43.77
27.77
22.94
18.12
14.68
QT4X20
89.80
71.00
57.70
47.60
38.50
22.00
QT4X24
89.80
71.00
57.70
47.60
38.50
22.00
anchor must be evaluated separately. Supports should be placed within 24 in. (610mm) of a splice on straight sections, and the span between supports should not exceed the length of tray. Additional supports will be required around bends and when the cable tray level changes. The load ratings of the hardware that supports the Quick Tray Wire Mesh Cable Tray must also be considered. Load ratings for some commonly used supports are shown in the Support Maximum Load table below. Once the load/foot has been determined, the weight on each support can be determined by multiplying the load/foot by the number of feet between supports. EXAMPLE: Weight of span = Load/foot * No. ft between supports Load/foot figure from the 2 x 2 in. cable tray with 40% fill ratio example: .98 lb/ft Weight of span = .98 * 5 = 4.9 lb Weight on support = weight of span / 2
Cross section- load versus span
Load in pounds
100 90 80
QT2 x 2 QT2 x 4
70 60 50 40 30
QT2 x 6(8) QT2 x 12 QT2 x 18(20) QT2 x 24 QT4 x 8 QT4 x 12
20 10 0
QT4 x 20(24)
5 ft
6 ft
7 ft
8 ft
9 ft
10 ft
Distance betw een supports
Support Maximum Load Catalog Number
Description
Bracket Width in. mm
Max. Load lbs
QTCB4
C Bracket
4
102
259
QTCB8
C Bracket
8
203
216
QTCB12
C Bracket
12
305
108
QTLB4
L Bracket
4
102
259
QTLB8
L Bracket
8
203
216
QTLB12
L Bracket
12
305
108
QTTH
Trapeze Hanging Clips
–
–
216
Data subject to change without notice
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National Electrical Code References 2002 NEC Cable Requirements
UL Grounding Requirements
The types of cables permitted by the 2002 NEC are indicated in Table 392.3 (A), Uses Permitted, Wiring Methods.They include:
All Quick Tray Wire Mesh CableTrays are UL classified with regard to suitability for use as an Equipment Grounding Conductor (EGC). Compliance with other appropriate NEC cable articles is required.The Cable Tray Institute (CTI) recommends compliance with National Electrical Manufacturers, NEMA, Standards Publications Nos.VE1 and VE2, and with the manufacturer's recommendations.
• Power and Control Tray Cable (Type TC) - NEC Article 340 • Power Limited Tray Cable (Type PLTC) - NEC Sections 725-61 and 725-71 • Instrument Tray Cable (Type ITC) - NEC Article 727 • Optical Fiber Cables - Article 770 • Fire Alarm Circuit Conductors - Article 760 • Communication Cables - Article 800 • Mineral Insulated (MI) Cable - Article 333 • Metal Clad (MC) Cable - Article 334 Other cables, particularly those specially approved for installation in cable trays, may also be permitted. Medium voltage (type MV) and single conductor cables in sizes 1/0 and larger are permitted, with some restrictions, in industrial establishments where qualified persons service the installation.
All Quick Tray Wire Mesh CableTray systems must be grounded [392.7(A)]. This is true whether or not the tray is being used as an equipment ground.There are many ways to meet this requirement.The most effective method is to treat the tray as if it were an equipment ground, meaning that the whole system is continuously bonded. However, the general requirement only calls for each section to be grounded. In order to be used as an equipment ground, several requirements must be met [392.7(B)]. First, the system must be bonded: where two sections meet, the connection should be solidly connected by an approved means, that is, a bolted connection. Additionally, supervision must ensure that only qualified personnel service the cable tray system [392.3(C)]. Therefore, when using Quick Tray Wire Mesh CableTray as an equipment grounding conductor, maintain continuous grounding by using the tray in conjunction with "nut and bolt" and steel splices as shown below.
18
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National Electrical Code References Additional Options for Grounding • Use a single conductor cable as the common EGC for all the circuits in the cable tray [NEC Section 392-3(b)(1) Exception 2]. • Use individual EGC conductors in each multiconductor cable in the cable tray (NEC Section 250-95).
Walking on Cable Trays Walking on cable trays must not be permitted. It violates the new version of NEMA standard VE-2, manufacturers' marking and recommendations, and the intent of the NFPA 70 Electrical Safety in Employee Work Practices.Walking on electrical equipment, conduits, cables or other electrical systems should also be avoided. In addition to the fall hazard, there is the risk of damage to equipment and possible contact with conductors.
High Voltage Cables High voltage cables can be installed in Quick Tray Wire Mesh CableTray. NEC permits type MC (Article 334) and type MV (Article 326) in industrial establishments where qualified persons will service the installation. Multiconductor cables rated over 600 volts must be separated from lower voltage cables by a separate cable tray or a solid fixed barrier.Type MC cables can be mixed with lower voltage cables. See NEC 392-6(f).
National Electrical Code Uses Permitted Article 392.3A Cable Type
Article
Armored Cable
320
Communications Raceway
800
Electrical Metallic Tubing
358
Electrical Nonmetallic Tubing
362
Fire Alarm Cables
760
Flexible Metal Conduit
348
Flexible Metal Tubing
360
Instrumentation Tray Cable
727
Liquid-tight Flexible Metal Conduit
350
Liquid-tight Flexible Nonmetallic Conduit
350
Metal-clad Cable
330
Mineral-insulated, Metal-sheathed Cable
332
Multiconductor Service Entrance Cable
338
Multiconductor Underground Feeder and Branch Circuit Cable
340
Multipurpose and Communications Cables
800
Nonmetallic Sheathed Cable
334
Power and Control Tray Cable Power-limited Tray Cablesa
336 –
Optical Fiber Cables
770
aSections 725-61 (c) and 721-71 (f).
Instrumentation, Signal, and Telecommunications Cables Instrumentation, signal, and telecommunications cabling should be separated from power cabling, both to meet NEC requirements and to avoid noise and electromagnetic pickup from adjacent power cables.This can be accomplished by a separate cable tray system or by a divider within a cable tray.The requirements for cables that have an outer metal armor are less stringent than for plastic jacketed cables.The general rule is to separate communication, control, signal, and instrumentation cabling from power cabling. Power cabling includes 460 volt motor power, 120 volt power, and lighting circuits. Note that 120 volt circuits can generate noise. Generally, a separation of two inches (51mm) is minimum, but the individual circuit and cable are the determining factors in separation requirements.
Data subject to change without notice
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Quick Tray Catalog Number Reference Guide To create a bill of materials (BOM) for a cable tray system, determine the number and cross-section of trays, as well as the type and number of splices, supports, and accessories. Cable Tray Straight Section Catalog Number QT2X2 QT2X4 QT2X6 QT2X8 QT2X12 QT2X16 QT2X18 QT2x20 QT2X24 QT4X4 QT4X8 QT4X12 QT4X16 QT4X18 QT4X20 QT4X24
Description 2 in. x 2 in. electro zinc cable tray straight section 2 in. x 4 in. electro zinc cable tray straight section 2 in. x 6 in. electro zinc cable tray straight section 2 in. x 8 in. electro zinc cable tray straight section 2 in. x 12 in. electro zinc cable tray straight section 2 in. x 16 in. electro zinc cable tray straight section 2 in. x 18 in. electro zinc cable tray straight section 2 in. x 20 in. electro zinc cable tray straight section 2 in. x 24 in. electro zinc cable tray straight section 4 in. x 4 in. electro zinc cable tray straight section 4 in. x 8 in. electro zinc cable tray straight section 4 in. x 12 in. electro zinc cable tray straight section 4 in. x 16 in. electro zinc cable tray straight section 4 in. x 18 in. electro zinc cable tray straight section 4 in. x 20 in. electro zinc cable tray straight section 4 in. x 24 in. electro zinc cable tray straight section
Quantity
For your convenience when ordering Unit Price Total Price
Description
Quantity
For your convenience when ordering Unit Price Total Price
Quantity
For your convenience when ordering Unit Price Total Price
Splicing Hardware Catalog Number QTSSW1
Bag of 50, 1 in. Square Splice Washers
QTSSW2 QTSSW3 QTBN1 QTFS QTFST QTTS QTUS10 QTUS43
Bag of 50, 1-1/2 in. Square Splice Washers Bag of 25, 2 in. Square Splice Washers Bag of 50, 1/4 in. Round Head Screws with Flange Nuts Bag of 50, Fast Splice Plates; one tool included per bag Tool for Fast Splice Plate connection Bag of 50 T Connection Splice Bars Bag of 50, 10 in. Universal Splice Bars 43 in. Universal Splice Bar
Hanging Supports Catalog Number QTTH QTTM QTCB4 QTCB8 QTCB12 QTSS QTSHSB QTQHA QTCH12 QTCH24 QTLB16 QTLB20 QTLB24
20
Description Bag of 50 Trapeze Hanging Clips, Hex nuts required, 1/4 in. to 3/8 in. 39 in. Trapeze Mount. Use with L bracket or 2 threaded rods 4 in. C Bracket 8 in. C Bracket 12 in. C Bracket Suspension Shoe (for use with CAT 30) Bag of 50 Single Hanger Suspension Brackets for 1/4 in. threaded rods, hex nuts required (for use with CS profiles only) Bag of 50 Quick Hanging Accessories for CS Brackets 12 in. Center Hanger 24 in. Center Hanger 16 in. L Hanger 20 in. L Hanger 24 in. L Hanger
Data subject to change without notice
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Quick Tray Catalog Number Reference Guide Wall Supports Catalog Number
Description
QTWMA
Wall Mount Attachment
QTSIWS
Snap-In Wall Hanger Support
QTLB4
4 in. L Bracket
QTLB6
6 in. L Bracket
QTLB8
8 in. L Bracket
QTRWB4
4 in. Reinforced Wall Bracket
QTRWB6
6 in. Reinforced Wall Bracket
QTRWB8
8 in. Reinforced Wall Bracket
QTRWB12
12 in. Reinforced Wall Bracket
QTRWB16
16 in. Reinforced Wall Bracket
QTRWB20
20 in. Reinforced Wall Bracket
QTRWB24
24 in. Reinforced Wall Bracket
Quantity
For your convenience when ordering Unit Price Total Price
Quantity
For your convenience when ordering Unit Price Total Price
Quantity
For your convenience when ordering Unit Price Total Price
Under Floor Supports Catalog Number
Description
QTUFC
Under Floor Support Clamp
QTUFS
2.5 in. High Under Floor Support
QTUFS6X8
6 in. High x 8 in. Long Under Floor Support
Accessories Catalog Number
Description
QTDS2
2 in. Divider Strip
QTDS4
4 in. Divider Strip
QTBC
Bolt Cutter
QTDO
12 in. Cable Drop Out Accessory
QTDO4
4 in. Cable Dropout
QTWTB
Wall Termination Bracket
QTCN25
1/4 in. Coupling Nut
QTCN38
3/8 in. Coupling Nut
QTFW25
1/4 in. Flat Washer
QTFW38
3/8 in. Flat Washer
QTHN38
3/8 in. Hex Nut
QTTHRD25
1/4-20 x 72 in. Threaded Rod
QTTHRD38
3/8-20 x 72 in. Threaded Rod
QTBC38
3/8 in. Beam Clamp
QTHN25
1/4 in. Hex Nut
Data subject to change without notice
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21
®
Quick Tray Application Guide
HOFFMAN 2100 Hoffman Way Anoka, Minnesota 55303-1745 U.S.A 763 421 2240 Fax: 763 422 2178
Litho in USA
©2005 Hoffman Enclosures, Inc.
User-00002
Rev. B 1/05
Quick Tray Application Guide
Quick Tray Wire Mesh Cable Tray Application Guide
Table of Contents Components . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2 Quick Tray Wire Mesh Cable Tray Bolt Cutter and Connectors Cutting the Cable Tray . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4 Creating a 90 Degree Bend . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6 Creating a Large Radius Bend . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8 Creating an Elbow . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10 Creating a 90 Degree Tee . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12 Creating a Y Junction Tee . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .13 Reducing Quick Tray Width . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .14 Changing Levels . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .15 Quick Tray Fill and Load Calculations . . . . . . . . . . . . . . . . . . . . . . . . . . .16 National Electrical Code References . . . . . . . . . . . . . . . . . . . . . . . . . . .18 Quick Tray Catalog Number Reference Guide . . . . . . . . . . . . . . . . . . . .20
Data subject to change without notice
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1
Components Quick Tray Wire Mesh Cable Tray The Quick Tray Wire Mesh Cable Tray comes in straight 10 ft. sections that are easily modfied and combined to fit almost any configuration. • Smooth, round wires minimize dust buildup and cable snagging. • Zinc plating resists corrosion. • Large 2 x 4 in. (51 x 102mm) mesh allows cable to be routed into and out of the tray at any point without cutting the tray • Available with either 2 or 4 in (51 or 102mm) sidewalls to hold cable in the tray and in a variety of widths to accommodate different numbers of cables Different cable tray sizes can be joined using the techniques described in this manual to make a truly custom installation using standard parts.
Catalog Number
Width in.
QT2X2
2
51
2
51
QT2X4
4
102
2
51
QT2X6
6
152
2
51
QT2X8
8
203
2
51
QT2X12
12
305
2
51
QT2X16
16
406
2
51
QT2X18
18
457
2
51
QT2X20
20
508
2
51
QT2X24
24
610
2
51
QT4X4
4
102
4
102
QT4X8
8
203
4
102
QT4X12
12
305
4
102
QT4X16
16
406
4
102
QT4X18
18
457
4
102
QT4X20
20
508
4
102
QT4X24
24
610
4
102
2
Depth in. mm
mm
Data subject to change without notice
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Components Bolt Cutter and Connectors Sturdy side action bolt cutter is specially designed to provide a flush cut and help create a protective coating for the new cut.
DataCom Products
Bolt Cutter
Catalog Number
Description
QTBC
Side Action Bolt Cutter
Catalog Number
Description
Pkg. Qty.
QTBN1
1/4 in. round head screws with flange nuts
50
QTSSW1
1 in. (25mm) square splice washer
50
QTSSW2
1 1/2 in. (38mm) square splice washer
50
QTSSW3
2 in. (51mm) square splice washer
25
Connectors Splice Washers
Splice Washers are used with QTBN1 screws and flange nuts for bolting turns, bends, and tees; connecting tray sections; and fastening splice bars.
Splice Plate and Connection Tool
Splice Plate quickly connects tray sections. Made of zinc-coated steel. Requires special installation tool, included with each package and available separately.
Description
Pkg. Qty.
QTFS
Splice Platea
50
QTFST Splice Plate Connection Tool a Includes one QTFST Splice Plate Connection Tool
Splice Bars
Splice Bars provide extra support and stability to tray sides when connecting tray sections with splice washers. Universal bars can be cut to fit with bolt cutters and bent for use in tees and elbows. Made of zinc-coated steel. Requires QTSSW1 1 in. (25mm) Square Splice Washers and QTBN1 Screws and Flange Nuts to fasten to side of tray. Data subject to change without notice
Catalog Number
☎
1
Catalog Number
Description
QTTS
T Connection Splice Bar
50
QTUS10
10 in. (254mm) Universal Splice Bar
50
QTUS43
43 in. (1092mm) Universal Splice Bar
1
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Pkg. Qty.
3
Cutting the Tray Always use the Hoffman side action bolt cutter to cut the Quick Tray Wire Mesh Cable Tray. This cutter allows precision cuts that minimize sharp edges that could snag wire. Its action also helps to protect the new cut from corrosion. Decide which wires must be cut When cutting for a bend, always review the cutting pattern for the tray size and desired bend before cutting. Red areas on the drawings should be removed.
Cut the first side wire Starting with the top side wire, position the cutting jaws on the cradle wire. Make the cut at an angle away from the new end.
4
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Cutting the Tray Cut the remaining side wires Cut the remaining side wires, remembering to rest the cutting jaws on the cradle wire and cut at an angle away from the new end. Make one clean cut to eliminate grinding or touch-up.
Cut the bottom wires Turn the tray over and cut the bottom wires from the underside. Always rest the cutting jaws on the cradle wire and cut at an angle away from the new end. Make one clean cut to eliminate grinding or touch-up.
Cut from the outside wires to the inside
That’s it! The cable tray is now ready for installation or for bending to the desired shape. Data subject to change without notice
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Creating a 90° Bend At the desired bend location, cut the wires shown in red for the width of the cable tray. Cut the side, then the bottom wires Cut all the side wires at the bend location for the tray size.
6
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Creating a 90° Bend Bend the cable tray Turn the tray on the uncut side. Smoothly bend the tray up until the inside edges closest to the uncut side meet.The bend radius should be 5 in. (120mm).The table shows the outer bend size for selected sizes.
Width of Tray in. mm
Size in.
mm
4
102
15
375
6
152
17
430
8
203
17
430
12
305
21
530
18
457
25
630
24
610
29
730
Secure the bend Fasten at the location shown with QTBN1 screws and flange nuts and the splice washers indicated for the tray width. 4 in./ 102mm
2 in./ 51mm
6 to 24 in./ 152 to 610mm
Data subject to change without notice
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Creating a Large Radius Bend Large radius bends are formed by removing the outside and bottom wires at the bend location.
Cut the side and bottom wires Remove the wires from the outside and the bottom of every other mesh section at the location of the bend. Follow the cutting pattern shown for the size tray.
8
Data subject to change without notice
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Creating a Large Radius Bend Bend the cable tray Lay the tray on a flat surface and pull the ends on the uncut side towards each other until the remaining cut sides almost touch at the corners.
Assemble the bends Fasten the inside of the bends together with the hardware shown in the drawings and in the table. A and B assemblies, where used, can be in any sequence on the inside of the bend.
2 in./ 51mm
Data subject to change without notice
4 to 24 in./ 102 to 610mm
☎
Width of Tray in. mm
Assembly Qty. A B
Radius in. mm
Size in.
mm
4
102
0
3
9
229
20
508
6
152
0
4
11
279
26
660
8
203
2
2
11
279
26
660
12
305
4
2
17
432
35
889
16
406
6
2
18
457
42
1067
18
457
9
0
28
711
51
1295
20
508
0
9
28
711
51
1295
24
610
1
10
28
711
54
1372
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Creating an Elbow Two cable trays can be joined to create elbows at various angles. Cut side wires from each tray Follow the cutting pattern for the tray width, removing the portions shown in red.
16 in./ 406mm
4 in./ 102mm
18 in./ 457mm 6 in./ 152mm
20 in./ 508mm 8 in./ 203mm
24 in./ 610mm
12 in./ 203mm
10
Data subject to change without notice
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Creating an Elbow Align the wires of the two trays at the desired angle Fasten the tray as shown. Use two QTBN1 screws and flange nuts and the splice washers indicated for the tray size for each joint. To form an adjustable angle, use one QTBN1 screw and flange nut and the splice washers indicated for the tray size, centered as shown under Adjustable Elbows. Be sure each splice washer is over two tray bottom wires.
Tray Width 4 in./ 102mm
Tray Width 8 to 18 in./ 203 to 457mm
Tray Width 6 in./ 152mm
Adjustable Elbows
Data subject to change without notice
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Creating a 90° Tee The T-connection splice bar connects the two sections of Quick Tray Wire Mesh Cable Tray to form a 90° tee. Cut the side wires Cut the side wires from the tray forming the top of the tee as shown in the cutting guide for the size tray.
Connect the cable trays Use two 10 in. Universal Splice Bars, bent in the middle to 90°, or two T Connection Splice Bars to connect the trays. If using T Connection Splice Bars, always put the long side parallel to the widest tray, or the one planned to carry the heaviest load.
T Connection Splice Bars
Universal Splice Bars
12
Data subject to change without notice
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Creating a Y-Junction Tee The Y-Junction tee requires cutting both sections of Quick Tray Wire Mesh Cable Tray. Cut both tray sections Cut and remove the wires indicated for the size tray.
Bend side wires to 45°
Connect the tray sections Form the Y by connecting the side wires of the two trays as shown.The universal connectors must be cut to 3 in. Also connect the trays with splice washers and QTBN1 screws and flange nuts. Use one on 4 and 6 in. trays, two on 8 and 12 in. trays, and three on 16 in. and wider trays.
Data subject to change without notice
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Reducing Quick Tray Width Reduce Quick Tray Wire Mesh Cable Tray width to connect to smaller tray by cutting side and bottom wires. Cut the side and bottom wires Cut the wires shown in the cutting guides to make a four inch or eight inch reduction in tray width.
4 in./102mm Reduction
Connect the uncut side of the trays Use a QTUS10 Universal Splice Bar with fasteners shown.
Bend the cut wires of each tray Use a QTUS10 Universal Splice Bar with fasteners on each pair of tray wires.
14
Data subject to change without notice
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8 in./203mm Reduction
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Changing Levels Quick Tray Wire Mesh Cable Tray is easily formed to go around obstacles by removing side wires and bending to the desired angle. Remove side wire sections Remove every other side wire section at the bend location from both sides of the tray.The number of side wire sections removed determines the radius of the bend.
Bend the tray Bend the tray smoothly up or down to go around the obstruction.
Data subject to change without notice
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Quick Tray Fill and Load Calculations The folllowing tables and formulas are provided to help determine how many cables can be safely carried by each size wire mesh cable tray tray and to determine the appropriate distance between supports for the load, based on number of cables, cable tray size, and bracket type. Wire Mesh Cable Tray Fill Ratio
Use the following formula to calculate the number of cables that will result in a particular fill ratio, where:
Fill ratio = Cross section of cable Cross section of tray
A = Inside tray area, in in.2 D = Cable diameter, in inches
According to NEC 392.9 (B), when using ventilated tray with multiconductor control cable, the sum of the crosssectional areas shall not exceed 50 percent of the interior cross section of the tray.
F = Fill ratio in %
The Quick Tray Wire Mesh Cable Tray Fill Table below shows the number of cables and the load in lbf/lineal foot developed by typical 4 pair and 6 pair cable weighing 20 lb/kft and 40 lb/kft, respectively.While this table is a useful guide, actual loads must be calculated using the cable specified.
N=
N = Number of cables The formula is F ( 100 ) * ( [(D/2)A2 * Π])
EXAMPLE: The installation will use CAT cable at .19 in. diameter, 20 lb per 1000 ft2.The desired fill ratio is 40%.The wire mesh cable tray tray is 2 in. (51mm) high by 2 in. (51mm) wide. A = 3.5 in.2 D = .19 in. F = 40% N=
40 3.5 ( 100 ) * ( [(.19/2) 2 * Π])
= 49 cables
Load/foot = 49 cables * 20 lb = 0.98 lb/ft 1000 ft.
Quick Tray Wire Mesh Cable Tray Fill Table at 50% Fill Catalog Number
Height in.
Width in.
Area in.2
CAT Cab Type (4 pair), .19 in. diameter, 20 lb/kft No. Cables Load at 50% Fill lbf/lineal ft
CAT Cab Type (6 pair), .26 in. diameter, 40 lb/kft No. Cables Load at 50% Fill lbf/lineal ft
QT2X2
2
1.75
3.5
62
1.24
32
1.28
QT2X4
2
3.75
7.5
133
2.66
70
2.8
QT2X6
2
5.5
11
195
3.9
103
4.12
QT2X8
2
7.5
15
266
5.32
141
5.64
QT2X12
2
11.5
23
408
8.16
216
8.64
QT2X16
2
15.5
31
550
11
291
11.64
QT2X18
2
17.5
35
621
12.42
329
13.16
QT2X20
2
19.5
39
692
13.84
367
14.68
QT2X24
2
23.5
47
834
16.68
442
17.68
QT4X4
4
3.75
15
266
5.32
141
5.64
QT4X8
4
7.5
30
532
10.64
282
11.28
QT4X12
4
11.5
46
816
16.32
433
17.32
QT4X16
4
15.5
62
1100
22
583
23.32
QT4X18
4
17.5
70
1242
24.84
659
26.36
QT4X20
4
19.5
78
1384
27.68
734
29.36
QT4X24
4
23.5
94
1668
33.36
885
35.4
16
Data subject to change without notice
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Quick Tray Fill and Load Calculations Supporting Quick Tray Wire Mesh Cable Tray The Quick Tray Wire Mesh Cable Tray is sized based on the number and type of cables required for the current and future need. A 50% fill ratio should equal the maximum number of cables pulled in a given cross section. Straight section supports installed at 5-foot (1.5m) centers are typical. For support spans greater than 5 feet (1.5m), cable loads must be evaluated to ensure that the span between the supports is suitable for the load.The support and Cable Tray Catalog Number
Maximum Load in lb/ft According to Span 5 ft 6 ft 7 ft 8 ft
9 ft
10 ft
QT2X2
17.17
12.54
7.51
6.04
4.77
3.86
QT2X4
18.10
14.00
11.30
9.30
7.40
5.10
QT2X6
25.10
19.80
16.00
13.40
11.00
9.00
QT2X8
25.10
19.80
16.00
13.40
11.00
9.00
QT2X12
36.00
27.70
22.10
18.10
14.60
10.50
QT2X18
65.00
45.50
33.80
26.10
19.40
15.00
QT2X20
65.00
45.50
33.80
26.10
19.40
15.00
QT2X24
67.00
48.70
37.80
30.30
23.70
17.00
QT4X8
43.80
35.90
30.10
25.40
21.20
17.00
QT4X12
57.95
43.77
27.77
22.94
18.12
14.68
QT4X20
89.80
71.00
57.70
47.60
38.50
22.00
QT4X24
89.80
71.00
57.70
47.60
38.50
22.00
anchor must be evaluated separately. Supports should be placed within 24 in. (610mm) of a splice on straight sections, and the span between supports should not exceed the length of tray. Additional supports will be required around bends and when the cable tray level changes. The load ratings of the hardware that supports the Quick Tray Wire Mesh Cable Tray must also be considered. Load ratings for some commonly used supports are shown in the Support Maximum Load table below. Once the load/foot has been determined, the weight on each support can be determined by multiplying the load/foot by the number of feet between supports. EXAMPLE: Weight of span = Load/foot * No. ft between supports Load/foot figure from the 2 x 2 in. cable tray with 40% fill ratio example: .98 lb/ft Weight of span = .98 * 5 = 4.9 lb Weight on support = weight of span / 2
Cross section- load versus span
Load in pounds
100 90 80
QT2 x 2 QT2 x 4
70 60 50 40 30
QT2 x 6(8) QT2 x 12 QT2 x 18(20) QT2 x 24 QT4 x 8 QT4 x 12
20 10 0
QT4 x 20(24)
5 ft
6 ft
7 ft
8 ft
9 ft
10 ft
Distance betw een supports
Support Maximum Load Catalog Number
Description
Bracket Width in. mm
Max. Load lbs
QTCB4
C Bracket
4
102
259
QTCB8
C Bracket
8
203
216
QTCB12
C Bracket
12
305
108
QTLB4
L Bracket
4
102
259
QTLB8
L Bracket
8
203
216
QTLB12
L Bracket
12
305
108
QTTH
Trapeze Hanging Clips
–
–
216
Data subject to change without notice
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17
National Electrical Code References 2002 NEC Cable Requirements
UL Grounding Requirements
The types of cables permitted by the 2002 NEC are indicated in Table 392.3 (A), Uses Permitted, Wiring Methods.They include:
All Quick Tray Wire Mesh CableTrays are UL classified with regard to suitability for use as an Equipment Grounding Conductor (EGC). Compliance with other appropriate NEC cable articles is required.The Cable Tray Institute (CTI) recommends compliance with National Electrical Manufacturers, NEMA, Standards Publications Nos.VE1 and VE2, and with the manufacturer's recommendations.
• Power and Control Tray Cable (Type TC) - NEC Article 340 • Power Limited Tray Cable (Type PLTC) - NEC Sections 725-61 and 725-71 • Instrument Tray Cable (Type ITC) - NEC Article 727 • Optical Fiber Cables - Article 770 • Fire Alarm Circuit Conductors - Article 760 • Communication Cables - Article 800 • Mineral Insulated (MI) Cable - Article 333 • Metal Clad (MC) Cable - Article 334 Other cables, particularly those specially approved for installation in cable trays, may also be permitted. Medium voltage (type MV) and single conductor cables in sizes 1/0 and larger are permitted, with some restrictions, in industrial establishments where qualified persons service the installation.
All Quick Tray Wire Mesh CableTray systems must be grounded [392.7(A)]. This is true whether or not the tray is being used as an equipment ground.There are many ways to meet this requirement.The most effective method is to treat the tray as if it were an equipment ground, meaning that the whole system is continuously bonded. However, the general requirement only calls for each section to be grounded. In order to be used as an equipment ground, several requirements must be met [392.7(B)]. First, the system must be bonded: where two sections meet, the connection should be solidly connected by an approved means, that is, a bolted connection. Additionally, supervision must ensure that only qualified personnel service the cable tray system [392.3(C)]. Therefore, when using Quick Tray Wire Mesh CableTray as an equipment grounding conductor, maintain continuous grounding by using the tray in conjunction with "nut and bolt" and steel splices as shown below.
18
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National Electrical Code References Additional Options for Grounding • Use a single conductor cable as the common EGC for all the circuits in the cable tray [NEC Section 392-3(b)(1) Exception 2]. • Use individual EGC conductors in each multiconductor cable in the cable tray (NEC Section 250-95).
Walking on Cable Trays Walking on cable trays must not be permitted. It violates the new version of NEMA standard VE-2, manufacturers' marking and recommendations, and the intent of the NFPA 70 Electrical Safety in Employee Work Practices.Walking on electrical equipment, conduits, cables or other electrical systems should also be avoided. In addition to the fall hazard, there is the risk of damage to equipment and possible contact with conductors.
High Voltage Cables High voltage cables can be installed in Quick Tray Wire Mesh CableTray. NEC permits type MC (Article 334) and type MV (Article 326) in industrial establishments where qualified persons will service the installation. Multiconductor cables rated over 600 volts must be separated from lower voltage cables by a separate cable tray or a solid fixed barrier.Type MC cables can be mixed with lower voltage cables. See NEC 392-6(f).
National Electrical Code Uses Permitted Article 392.3A Cable Type
Article
Armored Cable
320
Communications Raceway
800
Electrical Metallic Tubing
358
Electrical Nonmetallic Tubing
362
Fire Alarm Cables
760
Flexible Metal Conduit
348
Flexible Metal Tubing
360
Instrumentation Tray Cable
727
Liquid-tight Flexible Metal Conduit
350
Liquid-tight Flexible Nonmetallic Conduit
350
Metal-clad Cable
330
Mineral-insulated, Metal-sheathed Cable
332
Multiconductor Service Entrance Cable
338
Multiconductor Underground Feeder and Branch Circuit Cable
340
Multipurpose and Communications Cables
800
Nonmetallic Sheathed Cable
334
Power and Control Tray Cable Power-limited Tray Cablesa
336 –
Optical Fiber Cables
770
aSections 725-61 (c) and 721-71 (f).
Instrumentation, Signal, and Telecommunications Cables Instrumentation, signal, and telecommunications cabling should be separated from power cabling, both to meet NEC requirements and to avoid noise and electromagnetic pickup from adjacent power cables.This can be accomplished by a separate cable tray system or by a divider within a cable tray.The requirements for cables that have an outer metal armor are less stringent than for plastic jacketed cables.The general rule is to separate communication, control, signal, and instrumentation cabling from power cabling. Power cabling includes 460 volt motor power, 120 volt power, and lighting circuits. Note that 120 volt circuits can generate noise. Generally, a separation of two inches (51mm) is minimum, but the individual circuit and cable are the determining factors in separation requirements.
Data subject to change without notice
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Quick Tray Catalog Number Reference Guide To create a bill of materials (BOM) for a cable tray system, determine the number and cross-section of trays, as well as the type and number of splices, supports, and accessories. Cable Tray Straight Section Catalog Number QT2X2 QT2X4 QT2X6 QT2X8 QT2X12 QT2X16 QT2X18 QT2x20 QT2X24 QT4X4 QT4X8 QT4X12 QT4X16 QT4X18 QT4X20 QT4X24
Description 2 in. x 2 in. electro zinc cable tray straight section 2 in. x 4 in. electro zinc cable tray straight section 2 in. x 6 in. electro zinc cable tray straight section 2 in. x 8 in. electro zinc cable tray straight section 2 in. x 12 in. electro zinc cable tray straight section 2 in. x 16 in. electro zinc cable tray straight section 2 in. x 18 in. electro zinc cable tray straight section 2 in. x 20 in. electro zinc cable tray straight section 2 in. x 24 in. electro zinc cable tray straight section 4 in. x 4 in. electro zinc cable tray straight section 4 in. x 8 in. electro zinc cable tray straight section 4 in. x 12 in. electro zinc cable tray straight section 4 in. x 16 in. electro zinc cable tray straight section 4 in. x 18 in. electro zinc cable tray straight section 4 in. x 20 in. electro zinc cable tray straight section 4 in. x 24 in. electro zinc cable tray straight section
Quantity
For your convenience when ordering Unit Price Total Price
Description
Quantity
For your convenience when ordering Unit Price Total Price
Quantity
For your convenience when ordering Unit Price Total Price
Splicing Hardware Catalog Number QTSSW1
Bag of 50, 1 in. Square Splice Washers
QTSSW2 QTSSW3 QTBN1 QTFS QTFST QTTS QTUS10 QTUS43
Bag of 50, 1-1/2 in. Square Splice Washers Bag of 25, 2 in. Square Splice Washers Bag of 50, 1/4 in. Round Head Screws with Flange Nuts Bag of 50, Fast Splice Plates; one tool included per bag Tool for Fast Splice Plate connection Bag of 50 T Connection Splice Bars Bag of 50, 10 in. Universal Splice Bars 43 in. Universal Splice Bar
Hanging Supports Catalog Number QTTH QTTM QTCB4 QTCB8 QTCB12 QTSS QTSHSB QTQHA QTCH12 QTCH24 QTLB16 QTLB20 QTLB24
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Description Bag of 50 Trapeze Hanging Clips, Hex nuts required, 1/4 in. to 3/8 in. 39 in. Trapeze Mount. Use with L bracket or 2 threaded rods 4 in. C Bracket 8 in. C Bracket 12 in. C Bracket Suspension Shoe (for use with CAT 30) Bag of 50 Single Hanger Suspension Brackets for 1/4 in. threaded rods, hex nuts required (for use with CS profiles only) Bag of 50 Quick Hanging Accessories for CS Brackets 12 in. Center Hanger 24 in. Center Hanger 16 in. L Hanger 20 in. L Hanger 24 in. L Hanger
Data subject to change without notice
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763 422 2211 • FAX 763 422 2600 • www.hoffmanonline.com
© 2004 Hoffman Enclosures Inc.
Quick Tray Catalog Number Reference Guide Wall Supports Catalog Number
Description
QTWMA
Wall Mount Attachment
QTSIWS
Snap-In Wall Hanger Support
QTLB4
4 in. L Bracket
QTLB6
6 in. L Bracket
QTLB8
8 in. L Bracket
QTRWB4
4 in. Reinforced Wall Bracket
QTRWB6
6 in. Reinforced Wall Bracket
QTRWB8
8 in. Reinforced Wall Bracket
QTRWB12
12 in. Reinforced Wall Bracket
QTRWB16
16 in. Reinforced Wall Bracket
QTRWB20
20 in. Reinforced Wall Bracket
QTRWB24
24 in. Reinforced Wall Bracket
Quantity
For your convenience when ordering Unit Price Total Price
Quantity
For your convenience when ordering Unit Price Total Price
Quantity
For your convenience when ordering Unit Price Total Price
Under Floor Supports Catalog Number
Description
QTUFC
Under Floor Support Clamp
QTUFS
2.5 in. High Under Floor Support
QTUFS6X8
6 in. High x 8 in. Long Under Floor Support
Accessories Catalog Number
Description
QTDS2
2 in. Divider Strip
QTDS4
4 in. Divider Strip
QTBC
Bolt Cutter
QTDO
12 in. Cable Drop Out Accessory
QTDO4
4 in. Cable Dropout
QTWTB
Wall Termination Bracket
QTCN25
1/4 in. Coupling Nut
QTCN38
3/8 in. Coupling Nut
QTFW25
1/4 in. Flat Washer
QTFW38
3/8 in. Flat Washer
QTHN38
3/8 in. Hex Nut
QTTHRD25
1/4-20 x 72 in. Threaded Rod
QTTHRD38
3/8-20 x 72 in. Threaded Rod
QTBC38
3/8 in. Beam Clamp
QTHN25
1/4 in. Hex Nut
Data subject to change without notice
☎
763 422 2211 • FAX 763 422 2600 • www.hoffmanonline.com
© 2004 Hoffman Enclosures Inc
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®
Quick Tray Application Guide
HOFFMAN 2100 Hoffman Way Anoka, Minnesota 55303-1745 U.S.A 763 421 2240 Fax: 763 422 2178
Litho in USA
©2005 Hoffman Enclosures, Inc.
User-00002
Rev. B 1/05
