Proper cable sizing promotes safety, efficiency, and dependability.
Important factors include:
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Current Carrying Capacity
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Voltage Drop
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Short Circuit Rating
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Environmental Conditions
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Cable Type and Insulation
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Regulatory Compliance
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Installation Method
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Future Expansion and Cost
1). Current Carrying Capacity
The cable must be able to carry the intended load without overheating, taking into account the ambient temperature, grouping, & installation method.
2). Voltage Drop
Keep voltage drop to 2-5% to preserve equipment operation, and modify cable size for extended distances.
3). Short Circuit Rating
Determine whether the cable can sustain short-circuit currents based on fault levels & protective device clearance time.
4). Environmental Conditions
To select the appropriate insulation and protection, consider temperature, moisture, chemicals, & mechanical stress.
5). Cable Type and Insulation
Use copper or aluminum conductors with appropriate insulation (PVC, XLPE, etc.), shielding for EMI protection, & correct sheathing.
6). Regulatory Compliance
Adhere to NEC, IEC, BS, and IEEE standards for safety, fire resistance, & installation requirements.
7). Installation Method
Conduits, trays, buried, and aerial installations all have an impact on heat dissipation & performance.
8). Future Expansion and Cost
Plan for prospective load expansion while balancing cost versus long-term performance.