📝 Description

Used product – Original KOSTAL board for PIKO 10.1 three-phase photovoltaic inverter, identified on the PCB by the marking “AC-ANSCHLUSS-PLATTE”. It is the connection, switching, and filtering board for the AC section, installed between the inverter's conversion stage and the grid connection.
The board integrates numerous power and control components, including L1-L3 inductors, filter capacitors, K1-K8 relays, precharge/protection components, and control circuitry, as well as the three-phase L1-L2-L3-N terminal block visible on the front side.

⚙️ Main Specifications

• Manufacturer: KOSTAL
• Application: PIKO 10.1 photovoltaic inverter
• Configuration: Three-phase
• PCB designation: AC-ANSCHLUSS-PLATTE
• Type: AC power / connection board
• Function: AC section management, switching, and filtering
• Inductors: L1, L2, L3
• Power relays: K1–K8
• Filter capacitors
• EMI suppression components
• Measurement and control circuits
• AC terminal block L1 / L2 / L3 / N
• Auxiliary connectors and connection cables.

🔧 Main Functions

• Connection of the inverter's AC section to the grid
• Three-phase current filtering
• Reduction of electromagnetic interference
• Grid switching via relays
• Management of phases L1, L2, and L3
• Management of power-section switching functions
• Support for protection and control circuits of the AC section.

🔌 Purpose and Operation

The AC-Anschluss-Platte is one of the main modules of the PIKO 10.1 AC section.
The three L1-L3 inductors, together with the capacitors on the board, form the filtering system for the three-phase output. The K1-K8 relays perform switching and electrical-path management functions during the inverter's various operating conditions.
The presence of the L1-L2-L3-N terminal block clearly identifies the three-phase AC section connection.

🧩 Compatibility

The board is intended for the:

• KOSTAL PIKO 10.1 three-phase
  Compatibility must be verified by comparing PCB code, revision, component layout, connectors, and internal inverter configuration.
  It is important to distinguish it from the other PIKO 10.1 boards, such as the control board and DC-section boards.

⚠️ Typical Faults and Symptoms

A fault in the AC board may cause:

• failure to connect to the grid
• failure of AC synchronization
• failure to feed power into the grid
• protection tripping
• phase anomalies
• AC overcurrents or abnormal AC voltages
• failure of relay switching
• inductor overheating
• damaged capacitors
• deteriorated contacts or solder joints
• overheating marks on power traces.
  The symptoms are not necessarily attributable to the board alone: the electrical grid, IGBT stage, sensors, wiring, and control circuit must also be checked.

🚨 Possible Associated Errors

Possible inverter indications may concern:

• grid voltage
• grid frequency
• phase loss or anomaly
• failure to connect to the grid
• AC overcurrent
• output-stage protections.
  Any error codes should be considered diagnostic indications and not definitive proof that the board is faulty.

🔍 Diagnosis

Professional diagnosis may include:

1. visual inspection of relays, capacitors, and inductors;
2. inspection of solder joints and power traces;
3. continuity testing of inductors L1-L3;
4. checking relays K1-K8;
5. checking the capacitors;
6. checking connectors and cables;
7. checking terminals L1-L2-L3-N;
8. checking for short circuits between phases;
9. functional testing of the board installed in the inverter.

🛠️ Common Services in Case of Failure

• Power Board diagnostics
• Inductor testing
• Relay inspection
• Capacitor testing
• Power-trace inspection
• Solder-joint restoration
• Wiring inspection
• Complete board replacement
• Recovery as an original spare part from a decommissioned inverter.

🛠️ Applications

Suitable for:

• repair of KOSTAL PIKO 10.1 inverters
• AC-section maintenance
• replacement of the AC-Anschluss-Platte
• restoration of three-phase PIKO inverters
• recovery of photovoltaic equipment for spare parts.

🛡️ Product Condition

Used board, as shown in the photographs, with signs of handling and previous use.
Cables and connectors connected to the board are present, together with the original components.

📦 Package Contents

• 1 × KOSTAL PIKO 10.1 AC-Anschluss-Platte
• Complete board with components
• Relays, inductors, and capacitors as shown in the photographs
• Wiring and connectors present on the board.

🟢 Summary

KOSTAL PIKO 10.1 three-phase AC power / connection board – AC-Anschluss-Platte, intended for management of the inverter's AC output section. It integrates three-phase L1-L2-L3 filtering, K1-K8 power relays, capacitors, and control circuits, with L1-L2-L3-N terminal block.
It is a power component and not simply a filter board; for this reason, it has greater value as a complete original spare part for PIKO 10.1 maintenance.
Safety Note: The board operates in the AC power section. Any intervention must be carried out by qualified personnel, with the inverter completely disconnected and absence of voltage verified.