Over Voltage Fault

What does 05 mean?

This fault signifies that the DC Bus voltage has exceeded its maximum limit during operation. For 200-240V AC rated controllers, this trip occurs at 410V DC bus (290V AC incoming); for 380-460V AC rated controllers, it's 815V DC bus (575V AC incoming). This often happens due to motor regeneration, which can put excessive stress on the controller's internal components.

• Excessive AC supply voltage above the controller's maximum permissible input (e.g., >290V AC for 200-240V system).
• Regenerative energy from a rapidly decelerating high-inertia load exceeding the controller's braking capacity (without a braking resistor).
• Faulty braking resistor or braking chopper circuit allowing DC bus voltage to rise unchecked during deceleration.
• Sudden loss of motor load during high-speed operation, leading to regenerative energy feedback.
• Incorrectly set deceleration time (e.g., P1-04 too short) for the application's inertia.

Click steps to track your progress.

1. 1

   1. Measure incoming AC line voltage (L1-L2, L2-L3, L3-L1) at the controller's input terminals using a true RMS voltmeter. Verify it remains within the controller's specified operating range (e.g., 200-240V AC +/-10%).

2. 2

   2. Adjust deceleration time parameter (e.g., P1-04) to a longer duration, allowing more time for the motor's regenerative energy to dissipate.

3. 3

   3. If a braking resistor is installed, verify its resistance value (e.g., 100 Ohms) with an ohmmeter and inspect the wiring connections (e.g., terminals B1, B2) for integrity.

4. 4

   4. Measure the DC bus voltage (P+ to N-) during deceleration using a peak-hold function on a voltmeter or an oscilloscope to identify the exact peak voltage reached.

5. 5

   5. Check the functionality of the braking chopper transistor (if applicable) using a multimeter's diode test function or by observing switching action during deceleration.