When determining the cable size for installing a split air conditioner, several factors need to be considered, including the distance from the main distribution board (MDB). For longer distances, voltage drop becomes a critical concern to ensure the proper functioning and efficiency of the air conditioner. To calculate the appropriate cable size, you need to consider the following:
Voltage and Current Requirements: Check the specifications of the air conditioner to determine its voltage (V) and current (A) requirements. These values will be essential for the cable sizing calculation.
Voltage Drop Limit: Determine the acceptable voltage drop limit for the installation. The common practice is to limit the voltage drop to 3% for electrical appliances like air conditioners. However, in some cases, local electrical codes or guidelines may specify a different limit.
Conductor Material: Decide on the conductor material. Copper conductors are more conductive than aluminum and are commonly used for power transmission.
Single Phase or Three Phase: Determine if the air conditioner requires a single-phase or three-phase power supply.
Assuming the air conditioner requires a single-phase power supply, here's a general guide on how to calculate the cable size:
Step 1: Determine the Full Load Current (FLC) of the air conditioner: FLC (Amps) = Total BTU / (Voltage * Efficiency * Power Factor)
Step 2: Determine the voltage drop allowed (usually 3%): Voltage Drop (V) = 0.03 * Voltage (V)
Step 3: Calculate the Maximum Allowable Conductor Resistance (MAR): MAR (Ohms) = Voltage Drop (V) / FLC (Amps)
Step 4: Consult a cable manufacturer's or electrical code table to find the appropriate cable size that meets the calculated MAR value for the specific cable length (80 meters).
Keep in mind that this is a general guide, and specific cable sizing should always be performed by a qualified electrician or electrical engineer who can consider additional factors like ambient temperature, cable installation method, and local electrical codes.
Since the installation involves a significant distance, it is highly advisable to seek professional guidance to ensure compliance with electrical safety standards and efficient performance of the air conditioner. A qualified electrician can accurately calculate the cable size based on your specific air conditioner's requirements and the installation conditions.