Diagnostic APBox:
1. **Project Design Review:**
We verify the project configuration to ensure its correct implementation. We use the installer application to confirm the access mode configured in the APBox, which can be "grid-side," "load-side," or "before the meter."
2. **AC Voltage Measurement at Slot TB1 / L1+N and L2+N:**
After confirming the design configuration, we measure the AC voltage at slots TB1 / L1+N and L2+N. If the voltages are correct, we proceed to the next step. If there is no voltage reading, we check the wiring, power breakers, especially the Neutral wire.
3. **AC and DC Voltage Measurement at the DC Power Device:**
We measure the AC voltage at the upper slots (should be 120 VAC) and the DC voltage at the lower slots (should be 12 VDC) of the DC Power device. These values confirm the proper operation of the device. If there is no voltage, we must replace the DC Power.
4. **Relay Test:**
We verify the relay by measuring the AC voltage at the upper slots. A reading of 240 VAC indicates that the relay is in good condition. If there is no voltage, we must replace the Relay.
5. **Communication Cable Verification:**
We inspect and verify the communication cables to ensure they are correctly connected. In slot TB3, we bridge between DO+ and DO-. If the contactor closes correctly, it indicates that the APBox is functioning properly. We also verify the continuity of the communication cables.
6. **Communication Cable Inspection and Connection Verification:**
We inspect the communication cables, measure their continuity, and verify the connections in the DO/EPODI1 and RS485 green blocks. This step ensures proper connection. If the problem persists, we must replace the EMS.
After completing these steps, the system should be functioning correctly. If issues persist, further tests or adjustments may be necessary.