Pump controller displays E10 and refuses to start after a wiring change or new installation.

Safety: Do not attempt to run the pump until the earth fault is located. Isolate and lock off the supply.

• Insulation test: Using a megohmmeter, perform an insulation resistance test between each motor terminal and earth. Values below manufacturer recommendations (often <1 MΩ) indicate a fault.
• Inspect terminal box: Open the Certikin motor terminal box and check for water, condensation, or corrosion. Dry thoroughly and reseal with a new gasket if necessary.
• Check cable: Inspect the pump supply cable along its length for cuts or crushed sections. Replace if damaged.
• Verify bonding and earthing: Ensure the pump is correctly bonded to the pool equipotential bonding system and that the earth conductor is securely connected.

If insulation resistance remains low, the motor is unsafe to use and must be replaced by a qualified technician.