In this video, we explain how to solve poor communication issues in photovoltaic systems. Watch the step-by-step guide:

Key checks and solutions:

If the EMA data interval exceeds 1 hour or inverters frequently delay data → communication quality is poor

If the ECU is installed indoors or inside a junction box → use an extended antenna and mount it outdoors

Relocate the ECU to the center of the array, and install it in a waterproof box to shorten the communication distance

Reduce interference from nearby wireless sources (e.g., base stations, routers)

Install a signal amplifier/booster to enhance communication

If the issue persists, please contact APsystems technical support

In this video, we explain how to fix communication issues with some inverters when they fail to connect with the ECU. Follow our step-by-step troubleshooting process to restore stable communication.

Key points covered:

Restarting the ECU to trigger automatic firmware updates

Verifying the inverter UID in the ECU/EMA system

Re-establishing the Zigbee network for proper communication

Adjusting ECU placement or using antenna/cable extensions for better signal

Checking inverter status lights for normal or faulty operation

✅ Normal inverter operation lights:

Green (slow flash, 10s): Generating power + communicating

Green (fast flash, 2s): Generating power but no communication for 1+ hour

Red flashing: Inverter fault

⚠️ If a red light or abnormal status appears, please contact APsystems technical support.

In this video, we show step-by-step how to troubleshoot and repair a single non-working channel on your APsystems inverter. Learn how to swap channels, check DC voltage, ensure module compatibility, clean shaded or dirty panels, and secure DC connections to restore power generation.

Key topics covered:

Swapping a non-working channel with a working one

Measuring DC voltage and matching solar modules to the inverter

Identifying shading, dirt, or obstruction issues

Checking and redoing DC connector connections

When to contact APsystems technical support

⚡ Tip: Always ensure solar modules are compatible with your inverter’s MPPT/input and follow safety guidelines while performing maintenance.

In this video, we guide you through troubleshooting inverters that are not communicating with the ECU. Learn how to update ECU firmware, verify inverter UIDs, set up the Zigbee network, optimize ECU placement, use antenna extensions, and interpret inverter status lights to ensure proper operation.

Key points covered:

Triggering automatic ECU firmware updates

Verifying inverter UID in ECU/EMA

Establishing and re-establishing the Zigbee network

Optimizing ECU placement and using antenna extensions

Understanding inverter status light indications

⚡ Tip: Green lights indicate normal operation, while red or unusual light patterns signal issues. Contact APsystems technical support if problems persist.

In this video, we walk you through step-by-step solutions for fixing ECU network connection problems. Whether you’re using Wi-Fi or a wired connection, you’ll learn how to check ECU status lights, verify power supply, troubleshoot internet issues, and reconnect your ECU to the network.

Key points covered:

Checking ECU power and network indicator lights

Troubleshooting Wi-Fi connections with the EMA Manager APP

Ensuring proper router performance and ECU placement

Reconnecting ECU via wired network cables

When to contact APsystems technical support

⚡ Tip: A steady network connection is essential for reliable inverter communication and system monitoring.

In this video, we explain step-by-step methods to troubleshoot and repair an inverter DC input short circuit fault alarm. Learn how to identify wiring mistakes, check module health, and determine whether the problem comes from the inverter or the DC cables.

Key points covered:

Avoiding mixed connections between modules in the same channel

Ensuring connectors are correctly assembled and matched (positive to positive, negative to negative)

Checking DC extension cables for proper polarity

Measuring module voltage and verifying it is within safe limits

Identifying damaged modules causing DC alarms

Swapping inverter positions to confirm if the fault is with the inverter or cabling

⚠️ Safety reminder: Always follow electrical safety guidelines when handling DC connections.

In this video, we explain how to diagnose and fix the EMA overvoltage alarm on APsystems inverters. Learn how to identify whether the issue is caused by a single inverter, multiple inverters, or the AC bus itself.

Key points covered:

Checking whether the alarm occurs on one inverter or across multiple inverters

Inspecting AC connectors and bus connections for loose contacts or faults

Solutions for persistent overvoltage alarms:

Switch from single-phase to three-phase with balanced inverters

Replace the AC bus with higher capacity

Reduce PV-side transformer voltage slightly

When to contact APsystems technical support

⚠️ Note: Always follow electrical safety standards when handling inverter and AC bus connections.

In this video, we explain the method for troubleshooting multiple inverters AC abnormality when grid disconnection alarms are triggered. Learn step by step how to determine whether the issue comes from the branch, the AC bus, or the inverter itself.

Key points covered:

How to check if the affected inverters are on the same branch

Using EMA monitoring to confirm simultaneous disconnection events

Steps for breaker inspection and reset in the combiner box

Measuring AC voltages with a multimeter from the source to the end of the branch

Swapping inverters between branches to confirm whether the fault is inverter-related or AC bus-related

⚠️ Always ensure electrical safety and follow proper testing procedures during troubleshooting.

In this video, we explain how to repair AC abnormalities when an inverter triggers a grid disconnection alarm. Follow these steps to troubleshoot the issue:

Key checks and solutions:

Ensure the inverter connector is correctly connected to the AC connector

If loose or incorrectly installed, reinstall properly according to the manual

Use an AC clip (unlock tool) to detach the connector and measure AC bus voltage with a multimeter

If voltage is abnormal → trace wiring step by step from source to end

If voltage is normal → check for:
• Obstructions inside connectors (mud, stones) → clean them
• Bent or deformed pins → straighten with a screwdriver
• Y-shaped bus → consider installing an AC adapter

If no connector issues are found, swap the inverter with another to confirm if the AC component is faulty

⚠️ If the problem persists, please contact APsystems technical support.

In this video, we explain how to troubleshoot and fix the EMA overvoltage alarm for APsystems inverters. Follow these steps to identify and resolve the issue:

Key checks and solutions:

Determine if the alarm occurs on one inverter or multiple inverters

For single inverter alarms: Inspect AC connector pins for poor/loose contact

For multiple inverter alarms: Check AC bus and connector for faults

Possible solutions if the alarm persists:

Switch from single-phase to three-phase, balancing inverter loads

Replace the AC bus with higher capacity

Reduce PV-side voltage slightly if using a transformer

⚠️ If the overvoltage alarm continues after troubleshooting, please contact APsystems technical support.