Underground Cable Applications of CCA
1. Introduction
1.1 Underground Cable Benefits
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MEDIA TODO| Benefit | Description |
|---|---|
| Reliability | Weather independent |
| Aesthetics | Not visible |
| Safety | No overhead hazards |
| Right-of-way | Smaller footprint |
1.2 CCA Opportunity
| Factor | Cu | Al | CCA |
|---|---|---|---|
| Conductivity | High | Moderate | Good |
| Cost | High | Low | Moderate |
| Weight | Heavy | Light | Light |
| Termination | Easy | Difficult | Easier than Al |
2. Underground Cable Types
2.1 Distribution Cables
| Type | Voltage | Application |
|---|---|---|
| Secondary | <1 kV | Service to customer |
| Primary | 5-35 kV | Distribution |
| Transmission | >35 kV | Bulk power |
2.2 Installation Methods
| Method | Description | CCA Use |
|---|---|---|
| Direct burial | In ground | Possible |
| Conduit | In pipe | Good |
| Cable tray | Above ground | Good |
| Duct bank | Multiple conduits | Good |
2.3 Insulation Types
| Insulation | Temperature | Application |
|---|---|---|
| XLPE | 90°C | Standard |
| EPR | 90°C | Flexible |
| PILC | 85°C | Legacy |
3. CCA Advantages
3.1 Cost Savings
| Comparison | Material Savings |
|---|---|
| CCA vs Cu | 30-50% |
| CCA vs Al | Similar cost, better performance |
3.2 Weight Savings
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MEDIA TODO| Material | Weight per kcmil |
|---|---|
| Cu | 0.37 kg/m |
| CCA | 0.14 kg/m |
| Al | 0.12 kg/m |
3.3 Termination Benefits
| Advantage | Description |
|---|---|
| Cu surface | Standard terminations |
| No oxide issues | Unlike Al |
| Standard hardware | Cu-rated connectors work |
3.4 Corrosion Resistance
| Environment | Cu | Al | CCA |
|---|---|---|---|
| Underground | Good | Poor | Good |
| Moisture | Good | Poor | Good |
| Soil | Good | Variable | Good |
4. Installation Considerations
4.1 Handling
| Practice | CCA |
|---|---|
| Pulling tension | Similar to Al |
| Bending radius | Per cable spec |
| Training | Standard |
4.2 Splicing
| Method | CCA Suitability |
|---|---|
| Compression | Good |
| Resin splice | Good |
| Heat shrink | Good |
4.3 Termination
| Type | CCA Practice |
|---|---|
| Lug termination | Standard Cu lugs |
| Spade terminals | Standard |
| Stress cone | Standard |
4.4 Sizing
| Cu Size | CCA-80% Equivalent |
|---|---|
| 4/0 | 250 kcmil |
| 2/0 | 175 kcmil |
| 2 AWG | 3/0 |
5. Standards and Codes
5.1 Applicable Standards
| Standard | Scope |
|---|---|
| ASTM B566 | CCA wire |
| ICEA S-94-649 | Underground cable |
| NEMA WC 57 | Distribution cable |
5.2 Code Compliance
| Code | Requirement |
|---|---|
| NEC | Conductor sizing |
| NESC | Installation practices |
| Local codes | Jurisdiction-specific |
5.3 Utility Specifications
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MEDIA TODO| Utility Type | Typical Requirements |
|---|---|
| Investor-owned | Per utility spec |
| Municipal | May allow CCA |
| Co-op | Cost-sensitive |
6. Conclusion
6.1 Summary
| Advantage | CCA Underground |
|---|---|
| Cost | 30-50% savings vs Cu |
| Weight | 60% lighter than Cu |
| Termination | Easier than Al |
| Corrosion | Good |
6.2 Recommendation
CCA is suitable for underground applications where:
- Cost savings desired
- Cu terminations preferred
- Weight reduction beneficial
- Corrosion resistance needed
7. References
- ICEA S-94-649. (2020). Underground Cable Standard.
- ASTM B566-20. (2020). Copper-Clad Aluminum Wire.
Frequently Asked Questions
Is CCA suitable for direct burial applications?
Yes, CCA is suitable for direct burial when properly insulated with XLPE or EPR. The copper surface provides good corrosion resistance, and the cable should be installed per local code requirements for burial depth and protection.
How do CCA splicing methods compare to copper?
CCA can be spliced using compression connectors, resin splices, and heat shrink methods similar to copper. Use connectors rated for the conductor type and follow manufacturer torque specifications.
What insulation types are recommended for CCA underground cables?
XLPE (cross-linked polyethylene) and EPR (ethylene propylene rubber) are standard insulation choices, both rated for 90°C operation. XLPE is most common for new installations due to excellent electrical and mechanical properties.
Do utilities accept CCA for underground distribution?
Acceptance varies by utility. Many municipal utilities and cooperatives accept CCA for cost-sensitive projects. Always verify with the specific utility's material specifications before specifying CCA.