This section describes how to clear an AFCI alarm like DC arc fault.
AFCI alarm cannot be cleared automatically due to USA grid company requirements. Which means even when you fix the DC cable issue, you still need to clear this alarm manually then inverter can start up successfully. DC arc fault is usually caused by loose connections in the array rather than inverter hardware defects.
Please follow the steps below in order to solve the problem:
1. Turn off AC first and then open DC switches;
2. Unplug all the strings from the inverter. Mark the pairs. Make sure the string input connectors used in-box provided mating connectors and pins. If not, change them before proceeding to the next step;
3. Measure & record voltages on each string: Open circuit voltage Voc (V+ to V-), V+ to Ground, and V- to Ground. Take the readings until the values are stabilized. Identify & fix the outliers;
4. Plug in one string at a time. Turn on AC first and close DC switches. Clear the AFCI alarm using SUN2000 app with Advanced User;
5. If AFCI alarm reappears, that means there is a loose connection in that PV string. Thoroughly check all the string connectors, wires, J-boxes, PV modules. Locate the loose connections or other PV array defects and fix them;
6. Repeat Step 4 and 5 until all the strings are connected and no AFCI alarm appears again.
You can find below the steps on SUN2000APP to clear the alarm:
1. Log in SUN2000 APP with Advanced User and go into active alarm page.
2. Press the alarm until it been selected. Please see picture below.
3. Click “Clear”, then the alarm will be removed.
