- Solar and energy
- Solar inverter
DC Resistance Low - Power Off
Enphase DC Resistance Low - Power Off on a solar inverter: low insulation
Risk level
High
Professional inspection is recommended.
Urgency
High
Quick answer
An IQ8 microinverter measured low insulation resistance between the PV inputs and earth and stopped producing. The event stays until it is cleared through the IQ Gateway: call your installer and do not touch panels or connectors.
Safety first
Stop and check this first
- Do not disconnect panel or microinverter connectors. Enphase warns the DC conductors may be energised and forbids disconnecting them under load.
- Do not try to repair or open the microinverter. Enphase states it has no user serviceable parts and opening it voids the warranty.
Safe checks you can perform
- Event in Enphase monitoring
- Date and weather
- Clearing the event from the installer portal
- PV+ and PV- to earth measurement
Leave these tasks to a qualified professional
- Do not attempt this professional task: Sensor reset with Clear GFI
- Do not attempt this professional task: Insulation to earth on module and microinverter
- Do not attempt this professional task: Replace the faulty component
What a technician must be able to justify
Technician visit
These are the steps they must carry out and show you. Tick them as they work: if steps are skipped, do not accept a part swap.
These are not instructions for opening or handling the equipment yourself. They are the checks that should support a technical conclusion.
Sensor reset with Clear GFI
What they doThe installer sends the clear command from the Enphase Installer Platform to the affected microinverter and watches whether the condition returns.
They must show youthe event before and after the command.
In writingthe microinverter serial number and the result.
Insulation to earth on module and microinverter
What they doThey measure PV+ to earth and PV- to earth on the module and then on the microinverter.
They must show youthe readings at each point.
In writingwhich component gave the low reading.
Replace the faulty component
What they doThey replace the module or the microinverter based on the reading. For the microinverter, replacement goes through Enphase without opening it.
They must show youthe unit producing without the event.
In writingthe replaced part, its serial number and the RMA number if any.
Before accepting a part or repair
Nothing has been shown yet. Do not accept a part swap based on the code alone.
Follow these steps
Note: Follow the documented order. An error code identifies the affected system, but it does not prove by itself which part has failed.
Event in Enphase monitoring
- Who:
- you, with no tools.
- How:
- look for the DC Resistance Low - Power Off event in the Enphase monitoring you can access, or ask your installer to check it.
- Result that matters:
- that the event is active and how many microinverters it affects.
- If the event is listed:
- the condition is confirmed; call your installer.
- If it is not listed but production is down:
- it is a different issue; ask the installer to review the events.
- Evidence to keep:
- screenshot of the event with date and number of devices affected.
Evidence: IQ8MC, IQ8AC, IQ8HC, and IQ8X Microinverters Installation and Operation Manual (Great Britain), IOM-00029-4.0-EN
Date and weather
- Who:
- you, with no tools.
- How:
- note when the event appeared and whether there was rain or damp.
- Result that matters:
- whether it matches moisture, which Enphase lists as a cause.
- If it matches rain or damp:
- tell the installer; water may be getting in.
- If it appeared in dry weather:
- it points more to damaged insulation or a connector.
- Evidence to keep:
- note with date, time and weather.
Evidence: IQ8MC, IQ8AC, IQ8HC, and IQ8X Microinverters Installation and Operation Manual (Great Britain), IOM-00029-4.0-EN
Clearing the event from the installer portal
- Who:
- your installer, from the Enphase Installer Platform.
- How:
- under Events, open DC Resistance Low - Power Off, select the affected microinverter and use Tasks, Clear GFI.
- Result that matters:
- whether the condition clears and the unit resumes producing.
- If it clears and does not return:
- the cause was temporary; keep the record.
- If it does not clear or returns:
- the cause is still present; measurement follows and, if unresolved, Enphase support.
- Evidence to keep:
- screenshot of the event before and after clearing.
Evidence: IQ8MC, IQ8AC, IQ8HC, and IQ8X Microinverters Installation and Operation Manual (Great Britain), IOM-00029-4.0-EN
PV+ and PV- to earth measurement
- Who:
- qualified installer.
- How:
- measure resistance from PV+ to earth and from PV- to earth, first on the module and then on the microinverter.
- Result that matters:
- which of the two gives a low reading.
- If the low reading is on the module:
- the panel is the source and is replaced.
- If it is on the microinverter:
- the microinverter is replaced through Enphase.
- Evidence to keep:
- readings taken at each point.
The DC conductors are ungrounded and may be energised. Enphase forbids disconnecting AC or DC connectors under load. Competent personnel only.
Evidence: IQ8MC, IQ8AC, IQ8HC, and IQ8X Microinverters Installation and Operation Manual (Great Britain), IOM-00029-4.0-EN
Still not solved
If the error persists, stop here. See what the technician must do and show you.
Where this code applies
A code is meaningful only inside the right product and version context.
Primary scope
- System
- Solar and energy
- Brand
- Enphase
- Product type
- Solar inverter
Known code variants
- Enphase Clear GFI
- Enphase DC Resistance Low
- Enphase DC Resistance Low Power Off
- Enphase microinversor LED rojo fijo
- Enphase microinverter solid red LED
What it means
Each IQ8 microinverter has an insulation resistance sensor that measures from the positive and negative PV inputs to earth. If either drops below 7 kΩ, it stops production and raises the event. The condition persists even if the cause was temporary, until the sensor is reset through the IQ Gateway. Enphase attributes it to defective module insulation, faulty wiring or connectors, or moisture ingress, so the event does not say whether the panel or the microinverter is at fault.
Warnings and stop conditions
- Highsource verified
Do not disconnect panel or microinverter connectors. Enphase warns the DC conductors may be energised and forbids disconnecting them under load.
Evidence: IQ8MC, IQ8AC, IQ8HC, and IQ8X Microinverters Installation and Operation Manual (Great Britain), IOM-00029-4.0-EN
- Mediumsource verified
Do not try to repair or open the microinverter. Enphase states it has no user serviceable parts and opening it voids the warranty.
Evidence: IQ8MC, IQ8AC, IQ8HC, and IQ8X Microinverters Installation and Operation Manual (Great Britain), IOM-00029-4.0-EN
Symptoms and causes
Probable causes · in order
- PV module with defective insulationPossible
The low resistance is in the panel. It is confirmed when the PV+ and PV- to earth reading on the module is low and on the microinverter is not.
Evidence: IQ8MC, IQ8AC, IQ8HC, and IQ8X Microinverters Installation and Operation Manual (Great Britain), IOM-00029-4.0-EN
- Faulty wiring or connectorsPossible
Enphase names defective wiring or connectors. It is told apart by checking the DC connections between module and microinverter, which may need reseating or replacing.
Evidence: IQ8MC, IQ8AC, IQ8HC, and IQ8X Microinverters Installation and Operation Manual (Great Britain), IOM-00029-4.0-EN
- Moisture ingressPossible
Moisture can lower insulation temporarily. Even so, the event does not clear by itself: the sensor must be reset to see whether it returns.
Evidence: IQ8MC, IQ8AC, IQ8HC, and IQ8X Microinverters Installation and Operation Manual (Great Britain), IOM-00029-4.0-EN
- Faulty microinverterPossible
If the module reads correctly and the low reading is on the microinverter, Enphase says to replace it. It has no user serviceable parts.
Evidence: IQ8MC, IQ8AC, IQ8HC, and IQ8X Microinverters Installation and Operation Manual (Great Britain), IOM-00029-4.0-EN
Virtual technician
Does DC Resistance Low - Power Off still appear after these checks?
Answer a few questions to narrow down the likely cause and the safest next action. Guidance only - it never replaces a professional.
Sources and technical references
- 1
Enphase Energy · 2025 · manual
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