1. What is RW90 XLPE Cable?
RW90 XLPE cable is a single-conductor wire insulated with cross-linked polyethylene (XLPE), typically used for building wiring, electrical distribution, and panelboard applications. The designation "RW90" means:
R: Rubber-insulated (thermoset insulation)
W: Suitable for wet or dry locations
90: Maximum operating temperature of 90°C
RW90 XLPE cable offers excellent resistance to heat, UV, moisture, and chemicals. It comes in both copper and aluminum conductor options and is available in common sizes ranging from 12 AWG RW90 to 3/0 AWG RW90, suitable for various current-carrying applications.
2. Does RW90 Need Conduit?
1. Installation Environment
Whether RW90 XLPE cable requires conduit depends heavily on the installation environment:
Indoor dry locations: In these conditions, RW90 can often be installed without conduit, especially smaller sizes like 12 AWG RW90, which are typically hidden behind walls or above ceilings.
Wet or outdoor locations: If exposed to rain, humidity, or corrosive air, it's recommended or required to use conduit, especially for 10 AWG RW90 and 3/0 AWG RW90.
Underground installations: While RW90 has some moisture resistance, direct burial is not recommended. Use rigid or flexible conduit to protect against soil pressure, corrosion, and animal damage.
2. Local Electrical Code Requirements
RW90 cable installations must comply with national or regional electrical codes:
Canadian Electrical Code (CEC): Allows RW90 to be installed in conduit, on cable trays, or exposed, but mandates conduit in public areas or where physical damage is possible.
National Electrical Code (NEC - USA): While RW90 is not directly named, similar XLPE-insulated conductors must follow environmental guidelines. Larger cables like 3/0 AWG RW90 often require conduit for mechanical protection.
3. Safety and Maintenance
Even though RW90 offers good mechanical durability, conduit is recommended in high-traffic areas, near machinery, or where fire protection is a concern, to minimize risks and make maintenance easier.
3. Comparing RW90 XLPE with Other Cable Types
Engineers often compare RW90 with TW, THHN, or XHHW cables. Here's how they differ in terms of conduit usage:
| Cable Type | Requires Conduit? | Key Features |
|---|---|---|
| RW90 XLPE | Not always; depends on environment | Heat, moisture, flame-resistant; versatile |
| TW Cable | Usually yes | Only for dry locations; limited durability |
| THHN Cable | Typically installed in conduit | Heat-resistant, not UV-rated |
| XHHW Cable | Usually in conduit | Similar to RW90 but more common in conduit |
4. Practical Scenarios for RW90 Installation and Conduit Use
The following table shows typical scenarios involving RW90 XLPE, with conduit recommendations for various sizes like 10 AWG RW90, 12 AWG RW90, and 3/0 AWG RW90:
| Installation Environment | Conduit Recommended? | Typical Size Used | Reason |
|---|---|---|---|
| Indoor wall cavities | No | 12 AWG RW90 | Protected from damage |
| Industrial ceilings | Yes | 10 AWG RW90 | Risk of mechanical damage |
| Outdoor walls/balconies | Yes | 3/0 AWG RW90 | UV exposure and weather |
| Underground piping | Yes | All sizes | Moisture and corrosion risk |
| Cable tray installations | Depends on shielding | 3/0 AWG RW90 | Conduit optional if covered |
5. Conduit Considerations for Different RW90 Sizes
Conduit needs also vary by cable size:
12 AWG RW90: Common for lighting and outlet circuits; can be installed without conduit in protected spaces.
10 AWG RW90: Suitable for HVAC or small machinery circuits; conduit strongly recommended for high-heat or open installations.
3/0 AWG RW90: Used for panel feeders and building mains; due to its size, must be carefully planned for conduit space and bend radius.
Tip: When running multiple 10 AWG RW90 or 3/0 AWG RW90 cables in the same conduit, pay attention to heat derating factors and conduit fill percentages to ensure code compliance.
6. Best Practices for Installing RW90 XLPE Cable
To ensure long-term safety and performance, follow these best practices:
Check cable labeling for UV resistance if used outdoors
Always use conduit for outdoor or underground installs
Avoid direct contact with hot surfaces
Follow CEC or NEC guidelines-hire certified electricians
Use proper conduit diameter for larger cables like 3/0 AWG RW90
Dongguan Greater Wire & Cable Co., Ltd. has a strong international certification system to ensure that all products meet the market entry standards of mainstream markets around the world. Whether it is UL certification for the US market, Australian SAA, German VDE, or EU CE and international IEC, we have it all covered. Our cables are not only compliant, but also stable, durable and have outstanding performance. We welcome all kinds of international engineering customers to cooperate with us to share high-quality products and efficient services. Please contact us now to get the model information and cooperation plan you need.