User Manual 52 / 61 CPS Mini Central series
9.1.1 System fault
System fault (system faults are mainly caused by system instead of inverter, please check the items as instructed
below before replacing inverter).
Error message
Description
Suggestion
AC V Outrange
Utility grid voltage is out of permissible
range.
1. Check grid voltage.
2. Check AC wiring, especially the ground wire.
3. If the error message still exists despite the grid
voltage being within the tolerable range, contact
CyberPower.
AC F Outrange
Utility grid frequency out of permissible
range.
1. Check AC wiring and grid frequency.
2. If the error message is displayed despite the grid
frequency being within the tolerable range, contact
CyberPower
PV Isolation Low
Insulation problem.
1. Check if panel enclosure ground properly.
2. Check if inverter ground properly.
3. Check if the DC breaker gets wet.
4. Check the impedance of PV (+) & PV (-) between
ground (must be more than 1 MΩ). If the error
message is displayed despite the above checking
passed, contact CyberPower.
Residual I High
Leakage current too high.
1.Restart invert
2. If error message still exists, contact CyberPower.
Output High DCI
Output current DC offset too high.
1. Restart inverter.
2. If error message still exists, contact CyberPower.
PV Voltage High
The DC input voltage is exceeding the
maximum tolerable value.
1. Disconnect the DC wire immediately.
2. Check the voltage of each PV string with
multi-meter.
3. If the voltage of PV string is lower than 980V,
contact CyberPower.
Auto Test Failed
Auto test didn’t pass.
Restart inverter, repeat Auto Test, if problem still
exist, contact CyberPower.
Over Temperature
NTC OPEN or the temperature of
heatsink is too high.
If the ambient temperature of inverter is lower than
60°C, restart invert, if error message still exists,
contact CyberPower.