A borehole motor can be perfectly sized and installed, yet still perform poorly due to one overlooked issue: the cable.
Cable selection is not a minor detail. It directly affects motor performance, energy efficiency, voltage stability, and equipment lifespan.
Why Cable Selection Matters
Electric power travels through cables from the control panel or inverter to the motor. If the cable is too small or too long, resistance increases, causing voltage drop, power loss, and heat buildup.
What Is Voltage Drop?
Voltage drop is the reduction in voltage as electricity travels along a cable. Longer distances and smaller cables increase this effect.
In borehole systems, long cable runs are common due to depth and layout, making voltage drop a critical factor.
Effects of Low Voltage
Low voltage can cause:
– Poor motor starting
– Overheating
– Reduced efficiency
– Shortened motor lifespan
– Frequent system trips
Power Loss in Cables
Energy is lost as heat when current flows through a cable. Higher resistance leads to higher losses, increasing energy consumption and reducing system efficiency.
Factors Affecting Cable Size
– Motor power rating
– Supply voltage
– Cable length
– Starting current
– Installation method
– Ambient temperature
– Type of load
Why Borehole Systems Are Sensitive
Borehole systems often involve long distances, deep installations, and high loads, making proper cable sizing essential.
Common Mistake
Choosing cables based on price often leads to undersizing, causing inefficiency, overheating, and early equipment failure.
Benefits of Correct Cable Sizing
– Stable voltage supply
– Efficient motor operation
– Longer equipment life
– Reduced energy loss
– Improved system reliability
Solar Systems Consideration
In solar pumping systems, energy is limited. Cable losses reduce performance and daily water output, making proper sizing even more important.
Signs of Incorrect Cable
– Motor struggles to start
– Frequent tripping
– Reduced water output
– Overheating cables
– High power consumption
Conclusion
A borehole motor runs on the power that reaches it, not the power at the source. Proper cable selection ensures efficiency, reliability, and long-term performance.
Cable is not just wiring — it is a critical part of the system design.
Choosing the Right Cable: Power Loss and Voltage Drops in Borehole Motors
