Original OMRON AC Power Board designed for photovoltaic inverters of the KP Series, supplied with a dedicated repair kit specifically intended to resolve the common E5-1 Relay Error (Grid Relay Error).

This board manages the inverter’s connection to the electrical grid, controls the safety relays, performs AC filtering functions, and supervises all protection mechanisms required for compliant grid-connected photovoltaic operation.

The included repair kit contains the primary power relays and wear-prone components that commonly cause inverter shutdowns associated with the E5-1 error. Replacing these components often restores full functionality without the need to replace the entire inverter or power board.

🔄 Compatibility

Compatible with the following photovoltaic inverters:

• OMRON KP100L
• OMRON KP125L
• OMRON KP150L

⚙️ Technical Specifications

• Product Type: AC Power Board
• Application: OMRON Three-Phase Photovoltaic Inverters
• Grid connection management
• Anti-islanding protection circuitry
• High-capacity safety relays
• High-reliability AC filter capacitors
• Relay status monitoring and contact verification
• Integrated inverter diagnostic support
• E5-1 repair component kit included
• Internal inverter installation

🔧 Main Functions

• Connection of the inverter to the utility grid
• Automatic disconnection during fault conditions
• Grid relay monitoring and verification
• AC electrical protection management
• Grid synchronization control
• Anti-islanding operation support
• AC noise and transient filtering
• Continuous safety circuit monitoring
• Relay self-test and verification functions

🔌 Purpose and Operation

The AC Power Board serves as the interface between the inverter and the electrical grid. It receives power processed by the inverter's conversion stages and manages its safe injection into the utility network.

It is one of the most important components responsible for:

• Photovoltaic energy export
• Grid synchronization
• Electrical safety
• Inverter protection
• Compliance with grid connection standards

🧩 Role Within the Inverter System

Within the photovoltaic system, the AC Power Board performs the following tasks:

• Receives power generated by the inverter.
• Verifies grid presence and quality.
• Controls the grid interface relays.
• Executes startup safety tests.
• Connects the inverter to the utility network.
• Instantly disconnects the system in case of faults or abnormal operating conditions.

Without this board, the inverter cannot export energy to the grid.

⚠️ Typical Failures and Symptoms

Worn Grid Relays

Symptoms:

❗ Relay contact deterioration
❗ Grid connection failures
❗ E5-1 errors

Welded Relay Contacts

Symptoms:

❗ Safety self-test failure
❗ Relay stuck closed
❗ Grid relay alarms

Degraded Capacitors

Symptoms:

❗ Electrical instability
❗ Random inverter faults
❗ Startup issues

Overheated Components

Symptoms:

❗ Burn marks or discoloration
❗ Reduced reliability
❗ Unexpected shutdowns

Oxidized Connections

Symptoms:

❗ Intermittent operation
❗ False contact detection
❗ Communication interruptions

Relay Verification Circuit Failure

Symptoms:

❗ Startup test failure
❗ Persistent relay alarms
❗ Inverter unable to connect to grid

🚨 Errors Potentially Resolved with the Included Repair Kit

Replacing the relays and associated components included in the kit may help resolve:

• E5-1 Relay Error
• Grid Relay Error
• Relay Check Error
• Relay Verification Error
• AC Relay Fault
• Grid Connection Fault
• Mains Relay Failure
• Anti-Islanding Fault
• Startup Relay Error
• Relay Contact Error

Error names may vary depending on inverter firmware revision.

🛠 Applications

• Repair of OMRON KP Series photovoltaic inverters
• AC Power Board refurbishment
• Resolution of E5-1 relay faults
• Preventive inverter maintenance
• Utility-scale solar inverter servicing
• Industrial photovoltaic system repairs
• Specialized inverter service centers

✅ Benefits of the Repair Kit

• Dedicated solution for E5-1 relay errors
• Reduced maintenance costs
• Avoids replacement of the complete power board
• Fast inverter restoration
• Components selected for photovoltaic applications
• Ideal for maintenance technicians and repair centers
• Extends inverter service life
• Minimizes photovoltaic system downtime

📦 Product Condition

OMRON AC Power Board supplied with a professional repair kit specifically designed for E5-1 relay-related faults. Intended for maintenance, refurbishment, and repair of OMRON KP Series photovoltaic inverters rated at 100 kW, 125 kW, and 150 kW.

Suitable for both preventive and corrective maintenance of grid relay circuits and AC connection stages.

🟢 Summary

The OMRON KP100L AC Power Board with E5-1 Error Repair Kit is a professional repair solution for OMRON KP100L, KP125L, and KP150L photovoltaic inverters. Designed to address common relay-related failures, including the E5-1 Grid Relay Error, this package provides an effective and cost-efficient method to restore inverter operation, improve reliability, and reduce system downtime.