3M TTS-5-1-OJ, Application Manual

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To use the 3M Heat Trace Bill of Materials Tool, visit 3M.ca/HeatTrace To use the 3M Heat Trace Bill of Materials Tool, visit 3M.ca/HeatTrace
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Note: Due to TTS™ Self-Regulating Heating Cable self-regulating feature, TTS™ Self-Regulating Heating Cable will increase power when exposed to ice and snow.
When the cable has cleared the area, the power output will decrease, reducing energy consumption.
Heating Cable Length Multipliers
Metal Roofs
Select a multiplier from the examples shown based on the type of roofing material utilized. If gutters and downspouts
will also require protection, be sure to add the cable requirements (see
Table 2.2.3
) to the roof overhang footages.
Metal roofing materials such as standing seam or corrugated, as well as tile/concrete
roofing materials that have distinct ridges or grooves, must be properly addressed
when installing heat tracing. Metal roofs in particular pose an avalanche potential
that could damage the heating cable if it were installed in a serpentine pattern. To
combat this, the cable is installed parallel to the standing seams or along the length
of a corrugation. This partial sketch depicts TTS™ Self-Regulating Heating Cable as it
would be installed on a standing seam metal roof.
TTS Cable
Roof
RG-CMC
Gutter
Section Detail
To help determine the layout pattern for TTS™ Self-Regulating Heating Cable on metal roofs, use Table 2.2.1 in
conjunction with measurements of the spacing of the seams, corrugations or ridges in the roofing material. This spacing,
combined with the desired level of protection, will determine what multiplier to use to determine the footage of cable
required (heating cable does not have to be installed on every seam, corrugation, etc). Be sure to add extra cable to
reach the power connection point for each circuit.
To help determine the amount of cable required, select the overhang distance that fits the application and follow this
row across to the spacing pitch column that corresponds to the roofing material. The number where the row and
column intersect is the multiplier for that application. You then need to multiply this number by the number of linear
feet of roof eave to be protected and add sufficient cable to reach the power supply junction box plus any additional
cable to allow for on-site variations.
Spacing Pitch
Overhang
Distance
10" 12" 14" 16" 18" 20" 22" 24"
12"
18"
24"
30"
36"
4.2
5.4
6.6
7.8
9.0
3.7
4.7
5.7
6.7
7.7
3.3
4.2
5.0
5.9
6.7 3.0
3.8
4.5
5.3
6.0
Heavy Condition Multipliers Moderate Condition Multipliers
2.8
3.5
4.1
4.8
5.5
2.6
3.2
3.8
4.4
5.0
2.5
3.0
3.6
4.1
4.7
2.4
2.9
3.4
3.9
4.4
Table 2.2.1: Metal Roofs
Determining how far up the roof
the heating cable should travel
Overhang Distance
The heating cable should loop past
the point where an imaginary line
extending up from the inside wall
would pass through the roof.
All roof and gutter snow and ice melting systems should be controlled to turn the heating cable on and off as conditions
warrant. There are three easy ways to activate a roof and gutter system:
1. Manual On/Off Switch with Timer:
Economical and simple to install; requires diligence on the part of the operator.
2. Ambient Sensing Control: Turns system on and off based on ambient temperature. Heating cable will frequently be
energized during non-required times.
3. Automatic Control:
Roof- or gutter-mounted ice sensor turns system on when moisture is detected and
temperatures are in the range when freezing can occur on roof overhangs or in gutters.
Attention: The Canadian Electrical Code requires ground-fault protection of equipment to be provided for branch circuits supplying
fixed outdoor electric snow-melting equipment.
Step 5: Establish control method needed to operate system.
!