How To Calculate The Appropriate Size Of Mining Trailing Cable In Australia?
How To Calculate The Appropriate Size Of Mining Trailing Cable In Australia?
Blog Article
Selecting the correct size of Mining Trailing Cable is crucial to ensure safety, efficiency, and compliance with Australian standards.
Step 1: Determine the Electrical Load
The first step is to determine the total electrical load that the cable will carry.
This involves calculating the total power requirement (in watts or kilowatts) of the equipment the cable will supply.
For example, if the equipment requires 1000 watts, you need to convert this to amps using the formula:
Current (Amps)=Power (Watts)Voltage (Volts)Current
(Amps)=Voltage (Volts) Power (Watts)
For a 230V single-phase system, the current would be:
Current (Amps)=1000230≈4.35Amps
Current (Amps)=2301000≈4.35 Amps
Step 2: Consider the Voltage Drop
Voltage drop is the reduction in voltage in the electrical circuit between the source and the load.
Australian standards typically allow a maximum voltage drop of 5% for power circuits. The voltage drop can be calculated using the formula:
Voltage Drop (V)=Current (I)×Resistance (R)text{Voltage Drop (V)} = text{Current (I)} times text{Resistance (R)}Voltage Drop (V)=Current (I)×Resistance (R)
The resistance of the cable depends on the material (copper or aluminum), the length of the cable, and the cross-sectional area.
Step 3: Calculate the Length of the Cable Run
The length of the cable from the power source to the equipment and back impacts the size of the cable. Longer cable runs require larger cables to minimize voltage drop.
Step 4: Account for Environmental Factors
Consider the environmental conditions where the cable will be used. Factors such as ambient temperature, installation method (e.g., buried, in conduit, or exposed), and mechanical stress must be considered.
Higher ambient temperatures and harsher conditions typically require cables with better insulation and larger sizes.
Step 5: Select the Appropriate Cable Size
Using the information gathered, you can use a cable size calculator or reference tables from Australian Standards (AS/NZS 3008.1.1:2017) to determine the appropriate cable size.
These tables provide information on the current-carrying capacity of cables for different installation conditions.
Example Calculation
Assume you have a piece of equipment that requires 50 amps at 415 volts (three-phase) and the length of the cable run is 100 meters.
Using the voltage drop formula and the allowable voltage drop percentage, you can determine the minimum cross-sectional area of the cable required.
Current Calculation:
Load current = 50 amps
Voltage Drop Calculation:
Allowable voltage drop = 5% of 415V = 20.75V
Resistance Calculation:
Using tables or a calculator, find the cable size that limits the voltage drop to 20.75V over 100 meters.
Cable Size Calculators:
Online calculators can simplify this process by automating the calculations based on Australian standards.
Reference Tables:
AS/NZS 3008.1.1:2017 provides detailed tables for current-carrying capacity and voltage drop for various cable types and installation conditions.
Manufacturer Catalogues:
Cable manufacturers often provide detailed datasheets and selection guides that are specific to mining applications.
- By carefully considering these steps and utilizing the appropriate tools and resources, you can ensure the correct cable size for your mining application, which will enhance safety, efficiency, and compliance.