1. What Is RW90 Cable?
RW90 cable is a Canadian Standard Association (CSA) certified building wire primarily used for open wiring and in raceways in both dry and wet locations. The "RW" designation indicates suitability for wet locations, while the "90" signifies a maximum conductor temperature rating of 90°C. Typically, RW90 cables feature cross-linked polyethylene (XLPE) insulation, offering excellent heat resistance, moisture protection, and mechanical durability.
2. RW90 Cable Construction and Properties
2.1 Conductor Material
RW90 cables commonly utilize bare copper conductors that conform to ASTM B8 standards, ensuring good electrical conductivity and mechanical strength.
2.2 Insulation Material
The insulation is made of XLPE, providing
Heat Resistance: Stable operation within a temperature range of -40°C to 90°C.
Moisture Resistance: Suitable for damp environments, meeting CSA C22.2 No. 38 standards.
Mechanical Protection: Offers resistance to abrasion and physical damage.
2.3 Voltage Rating
RW90 cables are typically rated for 600V applications, with some variants available up to 1000V, catering to different electrical requirements.
2.4 Sunlight Resistance
Certain RW90 cables are marked as "Sunlight Resistant," indicating that their outer jackets are treated to withstand UV exposure, making them suitable for outdoor use.
3. Can RW90 Be Used Outdoors?
3.1 Conditions for Outdoor Use
RW90 cables can be used outdoors under the following conditions:
Sunlight Resistance: Ensure the cable is marked with "Sunlight Resistant" to withstand UV exposure.
Installation Method: Use appropriate installation methods, such as placing the cable in raceways, to protect it from direct sunlight.
Ambient Temperature: Verify that the cable's operating temperature range aligns with the local environmental conditions.
3.2 Scenarios Where RW90 Is Not Suitable
Despite its outdoor capabilities, RW90 cables may not be suitable in the following scenarios:
Direct Burial: RW90 cables are generally not designed for direct burial applications unless specified by the manufacturer.
High-Temperature Environments: In areas with temperatures exceeding the cable's maximum rating, alternative cables with higher temperature tolerances should be considered.
4. Relevant Electrical Codes and Standards for RW90
RW90 cables comply with several key standards:
CSA C22.2 No. 38: Specifies requirements for thermoset-insulated wires and cables.
UL 44: Sets standards for thermoset-insulated wires and cables.
NEC 310: Provides guidelines for the installation of conductors.
These standards ensure that RW90 cables meet safety and performance criteria for various applications.
5. Typical Outdoor Use Cases for RW90
RW90 cables are versatile and can be used in various outdoor applications, provided they meet the necessary conditions:
5.1 Industrial Building Exterior Wiring
RW90 cables are commonly used along the exterior walls of industrial buildings to supply power to outdoor equipment such as fans, pumps, and lighting systems. When selecting a cable, ensure it is marked as "Sunlight Resistant" to withstand UV exposure.
Case Study 1: Pulp Mill Project in British Columbia
In this project, several hundred meters of 6 AWG RW90 cable were installed along the exterior walls to connect multiple exhaust fans. The cables selected were CSA RW90 certified and UV-resistant, ensuring stable operation in extreme weather conditions for over five years without any failures.
5.2 Commercial Building Rooftop Wiring
Commercial buildings often have rooftop installations like HVAC systems, solar inverters, and security cameras. RW90 cables, especially those with CSA RW90 specifications, are suitable for installation on rooftops, provided they are protected from direct sunlight.
Case Study 2: Shopping Center Rooftop Renovation in Ontario
During the renovation, over 1000 meters of 6 AWG RW90 cable were installed for the rooftop HVAC system. The cables were placed in EMT metal conduits and were UV-resistant, meeting the energy efficiency requirements and passing electrical safety inspections.
5.3 Surface Raceway Installations (Rigid or PVC)
In residential or distribution upgrade projects, RW90 cables are often run through underground PVC or metal conduits. Since RW90 is not suitable for direct burial, conduit installation is the primary method for safe and compliant underground or surface installations.
Case Study 3: City Park Lighting System Upgrade in Alberta
Municipal engineers used RW90 cables installed in Schedule 40 PVC conduits to replace outdated lighting circuits. The installation ensured proper ventilation, enhancing system capacity and leveraging the cable's 90°C high-temperature rating to handle summer heat.
5.4 Outdoor Electrical Panel Connections
RW90 cables are also used to connect internal electrical panels to outdoor secondary panels, breaker boxes, or control systems. With appropriate conduit protection, their excellent insulation and flame-retardant properties make them ideal for short-distance, critical node applications.
5.5 Temporary Outdoor Construction Power
During construction projects, RW90 cables are often used for temporary outdoor power needs. Their flexibility and moisture resistance make them convenient for temporary wiring on construction sites. However, this usage should comply with CSA and NEC temporary power regulations and avoid prolonged exposure to sunlight.
These real-world examples and usage scenarios demonstrate that RW90 cable is a safe and efficient choice for outdoor environments-provided that cable RW90 is clearly marked as Sunlight Resistant and installed according to local electrical codes and best practices. Whether you are using CSA RW90 for rooftop power distribution or 6awg RW90 as a main feeder cable, its performance, reliability, and cost-effectiveness make it one of the most popular choices for outdoor electrical applications.
6. Alternatives to RW90 for Outdoor Use
In certain specific applications, other types of cables may be better suited than RW90. These include:
USE-2 Cable: Suitable for direct burial in electrical installations.
XHHW Cable: Offers higher temperature resistance, ideal for high-temperature environments.
TECK90 Cable: Provides superior mechanical protection and is designed for rugged and hazardous conditions.
Choosing the appropriate type of cable should be based on the specific project requirements and environmental conditions.
7. Best Practices for Outdoor RW90 Installation
When installing RW90 cable outdoors, the following best practices are recommended:
Avoid Direct Sunlight Exposure: Even though RW90 may be UV-resistant, prolonged exposure to direct sunlight should still be minimized.
Use Proper Installation Methods: Install in raceways or conduits to avoid direct contact with soil or ground surfaces.
Regular Inspections: Periodically inspect the cable's outer jacket and performance to detect and address any issues early.
8. RW90 Cable Cost and Availability
The cost of RW90 cable varies depending on brand, specification (such as 6awg RW90), and supplier. Generally, RW90 is considered a cost-effective solution for most building and industrial electrical installations. Popular manufacturers include Southwire, Shawflex, and Nexans, all of which offer CSA-certified RW90 products with various options for insulation, conductor size, and environmental resistance.
FAQ：
1. Is RW90 rated for wet locations?
Yes, RW90 is designed for use in both dry and wet environments.
2. Can RW90 be exposed directly to sunlight?
Only if the cable is marked "Sunlight Resistant".
3. Can I bury RW90 cable directly in the ground?
No, RW90 is not rated for direct burial unless installed in a proper conduit.
4. What temperature is RW90 cable rated for?
RW90 is typically rated for 90°C in dry and wet conditions.
5. What is the voltage rating for RW90?
RW90 is generally rated for 600V.
6. Can RW90 be used in conduit outdoors?
Yes, it's commonly used in EMT, PVC, or other conduits for outdoor installations.
7. Is RW90 suitable for cold climates?
Yes, especially the CSA-certified types, which are tested for Canadian winters.
8. How do I know if my RW90 cable is sunlight resistant?
Look for "Sunlight Resistant" or "SR" markings on the cable jacket.
9. Can RW90 be used in industrial environments?
Yes, it's widely used in both commercial and industrial settings.
10. Is RW90 more affordable than other outdoor-rated cables?
Yes, it's often more economical than armored or jacketed cables like TECK90.
The project is under tight schedule, but you still can't decide on the cable selection? Dongguan Greater Wire & Cable Co., Ltd. provides you with a one-stop solution. Our engineering consultant team can also provide you with cable wiring guidance and installation suggestions to ensure the smooth progress of the project. Call our service hotline or send an inquiry email immediately to communicate with our experienced team to make your project power system faster, more stable and safer!