SMA Sunny Boy Error Code 601

SMA PLC & VFD Critical DC Input

Model: Sunny Boy | Code: 601

Applicable Systems
Sunny Boy

Symptoms

Arc fault. The inverter's AFCI has detected an arc fault on the DC side. This is a fire risk and the inverterimmediately disconnects.

Possible Causes

  • Loose MC4 connector causing arcing under load
  • Damaged PV cable with intermittent contact
  • Corroded PV junction box contact
  • PV module internal cell string interconnect failure

Troubleshooting Steps

  1. Step 1: Check the equipment status and fault indicators to confirm the active fault code
    Fault indicator or HMI displays code 601 as active
  2. Step 2: Verify all electrical connections, wiring harnesses, and connector seating
    All connections secure, no corrosion, loose pins, or damaged wires
  3. Step 3: Check the system diagnostic buffer or event log for detailed fault information
    Diagnostic buffer shows the specific fault cause and timestamp
  4. Step 4: Verify power supply stability and environmental conditions
    Power supply stable, environment within specifications
  5. Step 5: Restart the equipment or power-cycle the control system
    Equipment restarts and enters normal operating state
  6. Step 6: Contact manufacturer support if the fault persists after all checks
    Support provides specific troubleshooting guidance

How to Reset

To reset: 1) Identify and fix the root cause described in the fault symptoms. 2) Press RESET on the HMI or controller, or power-cycle the equipment. 3) If the fault recurs, contact manufacturer service. Caution: Document the fault code and context before resetting.

Frequently Asked Questions

  • Q: What does fault code 601 mean on the SMA Sunny Boy?

    Fault 601 on the SMA Sunny Boy indicates: Arc fault. The inverter's AFCI has detected an arc fault on the DC side. This is a fire risk and the inverter immediately disconnects. Refer to the equipment manual and manufacturer support for specific troubleshooting steps.

  • Q: Can I continue operating the equipment with fault 601 active?

    No. The equipment has detected a fault condition and has taken protective action (typically stopping or derating). Continuing to operate without fixing the root cause may cause further damage. Always investigate and fix the fault before resuming operation.

Related SMA Fault Codes

Source: SMA Sunny Boy Inverter Installation and Operation Manual, SMA Official Documentation

Category: PLC & VFD