1.8 V supply low

What does 48 mean?

The 1.8 V DC internal power supply on the control card, crucial for its operation, is outside its allowable limits. This indicates a potential issue with the control card itself or an overvoltage condition if an option card is present. This can lead to erratic behavior or complete failure of the control card.

• Internal power regulator IC failure on the control card, leading to insufficient 1.8VDC output.
• Excessive current draw or short circuit on the 1.8VDC rail due to a component failure on the control card.
• Input voltage ripple or instability on the primary DC bus feeding the control card's internal power supply.
• Degradation of electrolytic capacitors or other passive components in the 1.8VDC regulation circuit over time.

Click steps to track your progress.

1. 1

   Measure the actual 1.8VDC supply at designated test points (e.g., TP1 or TP2) on the control card using a calibrated multimeter.

2. 2

   Perform a controlled power cycle of the drive and monitor if the fault immediately returns or after a period of operation.

3. 3

   Visually inspect the control card for any signs of damage, such as bulging capacitors, discolored components, or burn marks.

4. 4

   Verify the stability and correct voltage level of the higher DC rail (e.g., 5VDC or 24VDC) that supplies power to the 1.8VDC regulator.

5. 5

   Replace the control card if the 1.8VDC measurement is consistently out of tolerance and no external causes are identified.