Danfoss - Error 1027

If your Danfoss drive is flashing Error 1027, follow these steps to diagnose and potentially fix the issue: 1. Perform a Hard Reset

Understanding why this error happens helps isolate the root cause before replacing expensive components:

The motor is acting like a generator (e.g., during a quick deceleration of a high-inertia load), pushing power back into the drive and spiking the DC link voltage.

: In many Danfoss VFDs (Variable Frequency Drives), such as the VLT LD 302 danfoss error 1027

Switch the power back on and check if the error clears. 2. Inspect Hardware Connections A faulty connection can cause communication failure. Action: Check all connections to the control terminals.

Faulty option card, incorrect address, or damaged local cable segment. Isolate that drive’s cabling first.

Danfoss option cards like the VLT® MCA 101 (Profinet), MCA 104 (EtherNet/IP), or MCA 120 (Profibus) can fail due to ESD damage, power surges, or internal component aging. If your Danfoss drive is flashing Error 1027,

(depending on the drive kilowatt rating) to allow the DC-link capacitors to fully discharge.

fault. This means the inverter has detected an issue with the internal DC power stage, often triggered by improper string connections or internal hardware damage. Solis Inverters Troubleshooting Steps Perform a Hard Reset Disconnect all AC and DC power from the unit. Wait at least 5–10 minutes for the internal capacitors to fully discharge.

Commonly identified as an , this error indicates that the control card and the power card within the drive are unable to share data properly. In some specific configurations, it can also signal an overvoltage condition or a hardware failure related to the CAN telegram system. What Does Error 1027 Mean? Faulty option card, incorrect address, or damaged local

The drive is configured to receive cyclic telegrams from a fieldbus master (PLC, DCS, or BMS). Parameter defines what happens when those telegrams stop arriving. Error 1027 triggers when:

Ensure that any control, communication, or LCP cabling uses high-quality shielded twisted-pair cables with the shield correctly grounded. 3. Inspect Internal Board Interconnections If you are qualified to open the drive chassis:

Follow these steps sequentially to isolate, troubleshoot, and fix the underlying issue behind a Danfoss Error 1027 condition. 1. Perform a Full Hard Power Cycle

If you have an identical "known good" drive available, swap the control card into the failing unit. If the error disappears, you have confirmed that the original control card is defective and needs replacement. 5. Analyze the Alarm Log