Arc-Fault Alarm Troubleshooting for RHI-1P(5-10)K-HVES-5G

Note: Please first check the firmware version of the inverter and update it if the version is old. Please use the Current Firmware Versions List to determine if you need to update or not. 

The Solis RHI-1P(5-10)K-HVES-5G inverter series displays arc faults on the main screen under one of the statuses. If the fault is minor then it will clear quickly and if it clears before the data logger gets a chance to transmit the next data package then the fault will not show up on SolisCloud. Five consecutive faults (faults in the same hour) will result in a complete shutdown of the system which requires a manual reboot. Here is an example of what a 5G hybrid arc fault alarm will look like:
The number in the alarm code refers to the PV string number that the arc fault is being detected on. If this "01_ARC-FAULT" is displayed, then the arc-fault is being detected on string 1. To check if this is a true arc fault or a false arc fault, switch PV string 1 with PV string 3 and then run the system. If the next alarm to be displayed is "03_ARC-FAULT", then this is a real arc fault. If the next alarm is still "01_ARC-FAULT", then this is a false arc fault.

Within the "AFCI Set" menu there is an option to adjust the AFCI sensitivity. The default setting is 00, the most sensitive, and it can be adjusted up to 07, the least sensitive. The sensitivity should be set to 03 to prevent nuisance trips. 

For assistance troubleshooting a true arc fault, please see the article: Arc Fault Detection and Troubleshooting.

For assistance troubleshooting a false arc fault, please do the following things:

1. Make sure that the firmware is up-to-date - the older versions (DSP 08/HMI 08 and below) have a flaw with respect to AFCI detection. If the inverter is on an older version, please update it to the current one: Current Firmware Versions

2. If the system is using MLRSD then please read the section below

3. Contact Solis USA Technical Support at +1(866)-438-8408 to start a ticket

***If module-level rapid shutdown (MLRSD) installed please read this**

1. If you are using module-level rapid shutdown receivers, then be sure that there are no more than 16 devices on a single PV string as PLC signal degradation happens after 16 devices. Signal degradation can lead to abnormalities with the receivers that can be detected as an arc fault. 

2. Be sure that only one PLC signal transmitter is being used per site. If you have an external transmitter installed, please see Disabling the SunSpec MLRSD transmitter or Disabling the Tigo MLRSD transmitter to disable the internal transmitter depending on which one is in the inverter. Two transmitters on the same site can result in cross-talk, which will cause arc fault alarms to happen. Please see MLRSD Best Practices with Solis Inverters for help with this. 

3. It is not ok to install Tigo transmitters with SunSpec receivers or SunSpec transmitters with Tigo receivers. This will void the warranty for all components within the system. The reason for this is that the UL certifications are very specific as to what components can be installed together. But the main thing is that false arc-faults can and will happen.