Critical What does this mean?

A safety-rated fault — there may be a risk of electric shock, fire, or equipment damage. Do not try to fix this yourself. Call a qualified electrician.

SolarEdge Inverter 2X19 Isolation Fault — Meaning and Safe Next Steps

Error 2X19 means your SolarEdge single-phase inverter has detected an isolation fault — the insulation resistance between your solar array's DC wiring and earth has dropped below the safe limit (600 kΩ on single-phase inverters). Because this involves current leaking to ground, it is safety-critical: do not touch any DC wiring or the array, and have a certified installer find and fix the faulty string.

What should I do first?

Two quick questions — we'll point you to the right starting point.

Is this code still showing on your inverter's display?

What this code means

On a SolarEdge single-phase inverter running CPU firmware 3.19xx or later, error 2X19 is the "Isolation Fault" message. (On older 3.18xx firmware the same fault appears as error 25; on three-phase inverters it appears as 8x58.) Every time the inverter enters operational mode and starts producing power, it measures the resistance between the DC current-carrying conductors and ground. If the total combined isolation resistance is below 600 kΩ on a single-phase inverter, it refuses to connect to the grid and displays this fault instead.

In plain terms, electricity is leaking from the DC side of your system to earth somewhere it should not — through damaged module insulation, a pinched or unshielded wire, a failing power optimizer, or, less commonly, an internal inverter fault. The inverter is doing its job by stopping: feeding power while a ground leak is present would be dangerous, so it shuts down rather than operate.

One pattern worth knowing comes straight from SolarEdge's own isolation-fault application note: the fault can appear and then vanish on its own, especially in the morning. Overnight dew and moisture can temporarily drag the isolation value below the limit; as the array dries in the sun, the value recovers and the fault clears. A one-off morning occurrence that clears by itself is a very different situation from a fault that returns every day or stays on permanently — and SolarEdge recommends troubleshooting the fault as soon as it occurs, before a moisture-driven one has a chance to disappear.

What is this downtime costing you?

Rough estimate while your system isn't producing. Adjust the numbers to match your setup.

System size (kW) Peak sun hours / day Electricity rate ($/kWh)

–per day

–per week

–per 30 days

≈ – kWh of lost production per day.

Estimate only — assumes ~80% real-world output vs. nameplate. Actual losses depend on weather, shading, panel direction, and your tariff.

Common causes

Morning moisture or dew on the array temporarily dragging insulation resistance below the limit — the classic appear-and-clear pattern
Damaged module insulation, such as cracked backsheets or degraded seals letting water into the laminate
Pinched, chafed, or animal-chewed DC wiring creating a leakage path to ground
A failing power optimizer leaking current to its grounded frame
Unshielded or damaged wire runs exposing conductors to moisture and ground contact
An internal inverter fault (least common, diagnosed by eliminating the array-side causes)

Safe steps to try

Work top to bottom, ticking off each step as you complete it. 0 of 5 done.

Write down the exact code (2X19), the date, time, and weather conditions — your installer needs the pattern, especially whether it is a morning-only event
Check your SolarEdge monitoring portal for the inverter's last isolation value and whether the fault is a one-off or recurring
If it appeared on a damp morning and cleared by itself, watch whether it repeats over the next few mornings before calling anyone out
Do a visual check from the ground only: look for visibly damaged panels, hanging or damaged wires, or debris on the array — never climb onto the roof
Do not repeatedly reset the inverter or try to force it to produce; leave the system as it is and call your installer if the fault persists or recurs

Is your inverter still under warranty?

Before paying for a repair, check — your installer may fix this free.

Brand Year installed

Based on typical standard warranty terms — always confirm with your warranty card or installer paperwork, as terms vary by model, region, and purchase date.

When to call an electrician

Call your solar installer or a certified PV technician if the 2X19 fault appears more than once, stays on instead of clearing, shows up in dry weather, or your system's production has dropped. An isolation fault means current may be leaking to ground, so do not touch the DC wiring, the array frames, or anything connected to them. SolarEdge's own documentation states that only a certified PV installer may fix the faulty string, and its isolation-fault application note warns that troubleshooting PV ground faults can expose you to hazardous voltages and must be carried out by qualified personnel with proper safety equipment. If you smell burning, see scorch marks, or hear arcing from the array, switch the system off using the documented shutdown procedure and call a professional immediately.

Frequently asked questions

Can I reset a 2X19 isolation fault myself?

You can note the code and watch whether it clears on its own, but you should not try to fix it yourself. The fault means current is leaking to ground somewhere in the DC array, and finding it requires insulation testing on live DC wiring — work that SolarEdge reserves for certified installers with the right equipment.

Will a 2X19 isolation fault damage my solar panels?

The fault itself is the inverter protecting your system — it stops feeding power rather than operating with a ground leak. But the underlying cause (damaged insulation, a failing optimizer, water ingress) will not heal itself and usually gets worse over time, so a recurring fault needs professional attention before it becomes a bigger repair.

Why does 2X19 only appear in the morning?

Overnight dew and moisture can temporarily lower the array's insulation resistance below the 600 kΩ limit. As the sun dries the array, the value recovers and the fault clears. SolarEdge documents exactly this pattern. If it happens every morning, or starts appearing later in the day, have it investigated rather than assuming it is just dew.

Is an isolation fault dangerous?

It can be. Current leaking to ground can energize module frames, rails, and mounting hardware that should be safe to touch. That is precisely why the inverter shuts down instead of feeding power — and why you should not touch the array or any DC wiring while the fault is active. Call your installer.

What will the installer actually do to find it?

Following SolarEdge's isolation-fault application note, the installer checks the isolation value in the monitoring platform, then narrows it down by testing strings one at a time with an insulation tester — verifying the 1 V-per-optimizer safety voltage on each string — until the leaking module, optimizer, or wire is found and replaced.

Need a professional?

This fault is a safety risk — do not attempt to fix it yourself. Contact a qualified solar electrician in your area.

Sources: meaning and troubleshooting verified against the manufacturer's documentation — Troubleshooting SolarEdge Systems, Addendum (North America), MAN-01-00332-1.1 — Isolation Fault row (single-phase CPU v3.18xx: 25 → CPU v3.19xx: 2x19; three-phase: 121 → 8x58; 'PV solar array is not properly isolated from ground earth'; 'Only a certified PV installer must fix the faulty string before connecting it to the inverter'); corroborated by the SolarEdge Isolation Fault Troubleshooting Application Note v1.7 ('If an isolation error occurs, the LCD displays error 2x19 (single phase inverters) or 8x58 (three phase inverters)'; isolation checked at every operational start; 600 kΩ single-phase / 1 MΩ three-phase limit; morning-moisture appear-and-clear pattern)