Solar Lattice

Voltage measurement sensor fault

ID: fm:voltage-sensor-fault
IRI: https://solarlattice.org/kb/fm/voltage-sensor-fault
Status: active
Also known as: Vsense Error, Vsense Err, DC voltage measurement deviation

This fault means the inverter's internal voltage sensing circuit, or the sensor that measures DC voltage, has failed. SMA Sunny Central CP XT inverters report it as error 6427 or 6441, which mean a sensor error in DC voltage measurement. Yaskawa Solectria SGI-XTM inverters show Vsense Error on the user interface and record it in the event log. Other SMA inverters report a related measurement error when the DC or grid voltage reading deviates. On Yaskawa units, switch DC and AC off and restart the inverter. If the fault returns, turn the inverter off. This is an internal hardware fault, so contact the manufacturer's service line. An authorized service provider may need to inspect and service the inverter.

<!-- review notes

sentence 2: support check: partial - Errors 6427 and 6441 are sensor errors in DC voltage measurement, but the passages never name the Sunny Central CP XT model.
sentence 3: support check: partial - Vsense Error on the UI and Event Log Y are stated, but the passages don't name the SGI-XTM model.
sentence 5: support check: partial - u5 gives the off/restart step, but 'if the fault returns, turn the inverter off' is only loosely implied by the second action column.
sentence 6: support check: partial - Contact service and possible authorized-provider servicing are stated, but 'internal hardware fault' is only implied via internal failure of the sensing circuit. -->

Claims

`affects`

c1 verified · fact Inverter

SCCPXT-E7-WA-en-37 tbl=37.r1 h=785d03abb123
SGI 500-750XTM IOM DOCR-070506-D tbl=30.r11 h=251d0aca9ea4
SCCPXT-E7-WA-en-37 tbl=36.r19 h=adbb0b3e5531
SGI 500XT IOM DOCR-070254-B tbl=18.r7 h=9a224b5dfec7

verified by: review-workflowverified on: 2026-10-23

c2 verified · fact Voltage sensor

Sources describe an internal voltage sensing circuit or the sensor used to measure DC voltage inside the inverter.

SCCPXT-E7-WA-en-37 tbl=37.r1 h=785d03abb123
SGI 500-750XTM IOM DOCR-070506-D tbl=30.r11 h=251d0aca9ea4
SCCPXT-E7-WA-en-37 tbl=36.r19 h=adbb0b3e5531
SGI 500XT IOM DOCR-070254-B tbl=18.r7 h=9a224b5dfec7

verified by: review-workflowverified on: 2026-10-23

`presents_as`

c3 verified · fact Measurement signal error

Reported by the inverter as a sensor error when measuring DC voltage, or as a deviation in DC or grid voltage measurement.

SCCPXT-E7-WA-en-37 tbl=37.r1 h=785d03abb123
SCCPXT-E7-WA-en-37 tbl=36.r19 h=adbb0b3e5531
sbsxx-us-10-event-messages sec=h1 h=a056be6df42b

verified by: review-workflowverified on: 2026-10-23

`detected_by`

c4 verified · fact Inverter display check

The Yaskawa SGI-XTM shows the Vsense Error text on its UI and records it in the event log.

SGI 500-750XTM IOM DOCR-070506-D tbl=30.r11 h=251d0aca9ea4

verified by: review-workflowverified on: 2026-10-23

`mitigated_by`

c5 verified · fact Contact manufacturer service

All sources say to contact the manufacturer's service line; an authorized service provider may need to service the inverter.

SCCPXT-E7-WA-en-37 tbl=37.r1 h=785d03abb123
SGI 500-750XTM IOM DOCR-070506-D tbl=30.r11 h=251d0aca9ea4
SCCPXT-E7-WA-en-37 tbl=36.r19 h=adbb0b3e5531
SGI 500XT IOM DOCR-070254-B tbl=18.r7 h=9a224b5dfec7
sbsxx-us-10-event-messages sec=h1 h=a056be6df42b

verified by: review-workflowverified on: 2026-10-23

c6 verified · fact Inverter restart

One Yaskawa manual says to switch DC and AC off and then restart the inverter before getting service.

SGI 500XT IOM DOCR-070254-B tbl=18.r7 h=9a224b5dfec7

verified by: review-workflowverified on: 2026-10-23

Referenced by

SMA SC-CP-XT 6427 indicates c2
SMA SC-CP-XT 6441 indicates c2
Solis 1P-4G-US UN-G-V indicates c5
Solis S5-GC UN-G-V indicates c4
Solis S6-GC UN-G-V indicates c5
Solis S6-GU UN-G-V indicates c4
Yaskawa Solectria SGI-XTM Vsense Error indicates c3

Data