Fronius · PV inverters · Fronius Symo 3.0–20.0 (three-phase grid inverter, SnapINverter)
STATE 502Insulation error on the solar modules
Name in the manufacturer's documentation (service manual): Insulation error on the solar modules
[1]
In plain words (editorial)
Insulation error on the solar modules. A warning is shown on the display (it stays until acknowledged) while the inverter continues to operate.
When to call a service technician: If it keeps recurring, the installer must test the PV insulation – do not touch the DC cabling.
✎ editorial – written from the cited sources, not a manufacturer statement. Status: draft.
For technicians
Steps given by the manufacturer (source text)
- If this status code keeps recurring, contact your system engineer[2]
What the device does (source text)
- Warning message is shown on the display[3]
Notes from the documentation
- Class 5 codes are displayed until acknowledged by pressing a key; inverter continues to operate in the background[4]
⚠ Work on refrigerant circuits, mains electricity and PV DC wiring is for qualified technicians only.
The Polish page has more detail (plain-language explanation, safe checks, guides): Read in Polish →
Sources
Every statement has a footnote to the document and PDF page. “Quote verified” means the quote was found automatically in the text of that page.
- [1] Fronius Symo 3.0-3 – 20.0-3, Fronius Eco 25.0-3 – 27.0-3 – Operating Instructions (42,0410,2028, ed. 016-24082016) – distributor copy (42,0410,2028 (016-24082016)) , p. 49 manufacturer document – copy from a distributor quote verified
502 Insulation error on the solar
- [2] Fronius Symo 3.0-3 – 20.0-3, Fronius Eco 25.0-3 – 27.0-3 – Operating Instructions (42,0410,2028, ed. 016-24082016) – distributor copy (42,0410,2028 (016-24082016)) , p. 50 manufacturer document – copy from a distributor quote verified
If this status code keeps recurring, contact your system engineer
- [3] Fronius Symo 3.0-3 – 20.0-3, Fronius Eco 25.0-3 – 27.0-3 – Operating Instructions (42,0410,2028, ed. 016-24082016) – distributor copy (42,0410,2028 (016-24082016)) , p. 49 manufacturer document – copy from a distributor quote verified
Warning message is shown on the display
- [4] Fronius Symo 3.0-3 – 20.0-3, Fronius Eco 25.0-3 – 27.0-3 – Operating Instructions (42,0410,2028, ed. 016-24082016) – distributor copy (42,0410,2028 (016-24082016)) , p. 49 manufacturer document – copy from a distributor quote verified
These status codes are displayed until they are acknowledged by pressing a key