SolarEdge › Problems
SolarEdge isolation fault stops production
Your SolarEdge inverter shows an isolation fault, such as 18X86, and stops producing, often after rain or morning dew. This page covers what the lights and codes mean, what to check first, and the causes behind it.
What the lights mean
| What you see | What it means |
|---|---|
| Flashing green and flashing blue | AC is connected but the inverter is not producing, and its link to monitoring comes and goes. |
| Solid green and solid blue | Producing normally and connected to monitoring. |
Error codes that go with this problem
| Code | What it means |
|---|---|
| 18X86 or Isolation Error on the screen | The inverter found DC current leaking to ground and stopped producing. It can come back every time it rains and clear once the panels dry. |
| DC current leakage to ground has been detected, or isolation fault / ground fault in the app | SolarEdge's test found a leakage path to ground on the DC side, before startup or during production. Production is blocked until the path clears or is fixed. |
What to check first
- Note when the fault shows and what the weather was: for example a sunny morning that clears by midday, or every time it rains and clearing once the panels dry.
- Ask your installer to check the monitoring platform's alert history for when the isolation faults trigger. That shows when to be on site.
- Call your installer if the fault keeps coming back. If it follows early mornings, ask for a visit in that window, since once the dew has dried the fault may not show.
- If the breaker trips with sparks, ask your installer to open the inverter's bottom case and look for water residue.
Safety. Water inside the inverter has tripped the breaker with sparks. Before covers are opened the system must be de-energized and its DC voltage bled down; the inverter is safe to service below 50 volts DC.
The causes and the fixes
Partners see the causes behind this problem, most common first, the checks that tell them apart, and the fix for each, with part numbers and recent prices when a part is involved.