SolarEdge Error 38 — AC Frequency Fault

What Does This Error Mean?

Error 38 on a SolarEdge inverter means grid frequency is outside the country's allowed range (typically 49.5–50.5 Hz in EU, 59.3–60.5 Hz in North America). The inverter disconnects per grid code. Most events are transient — recurring Error 38 indicates a generator-fed installation or a very weak grid.

Affected Models

SolarEdge SE3000H
SolarEdge SE7600H
SolarEdge SE10000H
SolarEdge SE11400H-US
SolarEdge HD-Wave

Common Causes

Brief grid frequency excursion from a major fault elsewhere on the grid
Site fed by a small generator with poor frequency regulation
Site on a microgrid or island system with weak frequency control
Inverter measurement calibration drift (rare)
Grid-tied with very low system inertia

How to Fix It

Confirm whether Error 38 is recurring.

Check SolarEdge monitoring history. Single events from grid faults clear automatically. Repeat Error 38 daily indicates a chronic grid stability issue.
Note the time of day.

Error 38 at peak solar hours suggests grid frequency rising from PV oversupply. Error 38 at night (if you have storage) suggests a grid stability issue. Pattern helps narrow the cause.
Check generator-fed sites carefully.

If your site is on a generator (off-grid or backup), the generator's frequency regulation may be too poor for the inverter. Most SolarEdge inverters need a stable grid — generator backups need careful sizing and tuning.
Contact your utility for grid investigation.

Recurring Error 38 with utility-supplied power indicates grid issues. Document times and frequency readings (if available from monitoring). The utility may identify upstream issues affecting your area.
Ask installer about wider frequency settings.

Some jurisdictions allow installers to widen the inverter's frequency limits within regulatory tolerance. This is a workaround, not a fix — the underlying grid issue should still be addressed.

Frequently Asked Questions

Will Error 38 affect my solar production significantly?

Brief Error 38 events (a few seconds) cause minimal lost production. Frequent Error 38 (multiple times per day, several minutes each) can lose 5–15% of expected production. A monitoring report shows the impact precisely.

Can my SolarEdge work with a generator?

Some SolarEdge inverters work with generators if the generator has tight frequency and voltage regulation. The HD-Wave family is particularly sensitive. Discuss with your installer before relying on a generator-PV combination — many off-grid setups require AC-coupled or DC-coupled approaches.